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The objectives of this study are twofold: 1) investigate the material load-bearing percentages and forces’ transmission rules of grouted couplers in static testing; and 2) evaluate impact responses and failure processes of specimens under low-velocity impact. To conduct the first objective, precast concrete specimens with two different types of pier-footing connections are designed, cast, and tested under sequential compressive and lateral loads. The strain-time history at five critical areas on longitudinal reinforcements and GSSs are recorded and analyzed. The compressive and shear behaviors between the piers with couplers in the footing and those with connectors embedded in the pier base are then compared. Finally, the compressive and shear load transmission mechanisms from a detailed model perspective are proposed.

With the popularization of accelerated bridge construction (ABC), the utilization of splice sleeve connections has been researched to determine their performance using a variety of connection details and under several loading scenarios. However, fundamental research on the load distribution and load transfer mechanism within the sleeve region under the combination of compressive and shear loads are limited. Additionally, a few studies have conducted the dynamic analysis of the coupler (i.e. coupler, rebar and grout), but to date, no study can be found that assesses the connections in sequence with the encasing concrete to detail the load paths for the composite member, evaluates the dynamic behavior and failure modes of precast columns with connections at different locations columns under low-velocity impact loading, nor that determines non-visible damage within the post-impact sleeve. In this study, two groups of precast concrete specimens with grouted splice sleeve (GSS) connectors at different locations are tested. The two groups represent two typical connection details for bridge piers to footings: one with the sleeve in the top of the footing and one in with the coupler at the base of the column. This study is divided into two major parts: static and dynamic investigations. This study not only provides novel and in-depth insights into theoretical research on the mechanism of precast concrete construction utilizing a GSS system, but also contributes much-needed data of impact test of the precast columns and novel insights into residual bond strength analysis of the post-impact GSS connectors.

The Minnesota Department of Transportation (MnDOT) investigated the use of dowel bars with various anchoringmethods. This report examines the characteristics of various epoxy and grout anchorage systems at the interfacebetween new construction and existing concrete. Twelve different anchoring materials as well as various anchoringmethods were studied and compared to a control using no grout. This study did not examine the effects of thenumber of dowels used but instead was limited to the methods and materials used to anchor the dowels. Thisexperiment was performed on concrete panels in-house. The tube grout method exhibited the best visual andmagnetic imaging results. The evaluation methods did not clearly categorize the materials in order of performancebut showed advantages of cleaning the drill-hole prior to dowel placement as well as the merits and demerits ofusing a retaining collar. The results generally suggested the need for an actual deployment research project on actualpavement in real-world service conditions. The field experiment was reported in a separate document.

Microencapsulated phase-change-materials (PCMs) incorporated in cementitious grout can be used as a source of energy in an underground thermal energy storage system. Differential scanning calorimetry (DSC) is a widely used technique to measure the latent heat or specific heat of PCM-embedded cementitious materials. However, using milligram sample sizes (as required by DSC) of a cementitious material fails to represent the actual scale of cementitious components. This is the reason why, in the present paper, non-isothermal heat conduction microcalorimetry (MC) was evaluated as a tool for determining the thermal properties of PCM-embedded grout as well as pure PCM (three PCMs were used). An MC experimental protocol (using both single and 5–6 temperature cycles) was developed and used to measure latent heat and melting and crystallization temperatures, which were in good agreement with those reported for pure PCMs by the producers. In addition, the specific heats of the PCM-containing grout also agreed with measurements using the hot disk technique. Overall, the results show that the MC technique can be used as a potential standard method in determining thermal processes in complex systems, such as in PCM-embedded cementitious systems, where a large sample size is needed to represent the material., QC 20230824

Due to an increasing amount of aging tendencies in Swedish embankment dams, failures such as internal erosion has become a more common problem. Internal erosion is a phenomenon where certain soil material within the embankment dam is removed, often over a longer period of time. It is most common to occur at the inner core of the dam, and if it is allowed to continue for a longer time period the consequences can be disastrous. During the internal erosion, the inner material is washed out, creating larger voids and lowering the geotechnical stability of the dam. When larger voids start to appear, the seepage will increase allowing more material to be washed out and accelerating the process. In order to repair an embankment dam, exposed to inner erosion, it requires both the location of the faults as well as a suitable method of repairing. A method to repair internal erosion is by using grout and injecting it into the location of the fault. The knowledge regarding what type of grout and how it should be treated is today lacking. There are reasons to believe that a hardening mixture within an embankment dam using a till core will not cooperate well. For that reason, a grout with non-hardening properties is of interest. this thesis focuses on the Geomechanical strength parameters of two similar experimental non-hardening grouts. One with maximum grain size of 2 mm referred as grout 0/2, and one with maximum grain size of 4 mm, referred to as grout 0/4. The grouts consist of natural aggregates, calcium carbonate, water, bentonite, superplasticizer and defoamer. The grouts are evaluated by its undrained shear strength, water content, bulk- and dry density using fall cone tests and uniaxial compressive strength tests. To evaluate the grouts angle of friction and angle of dilatancy together with young’s modulus, consolidated, drained triaxial tests were performed. Three tests with different consolidation pressures (50, 150 and 300 kPa) were performed for each grout. Sinc, På grund av en ökad mängd med föråldrandetendenser hos svenska jordfyllningsdammar har brott så som inre erosion blivit ett alltmer vanligt problem. Inre erosion är ett fenomen där en viss jord inom jordfyllningsdammen är avlägsnad, generellt över en längre tidsperiod. Oftast inträffar detta vid den inre damkärnan och om erosionen är tillåten att fortskrida sig över en längre period kan konsekvenserna bli förödande. Inre erosion fungerar så att jordmaterial tvättas ut vilket skapar hålutrymmen och minskar den geotekniska hållfastheten för dammen. När större hålutrymmen bildats ökar läckaget som i sin tur tillåter mer material att bli urtvättat och processen blir accelererad. För att kunna reparera en jordfyllningsdam, utsatt för inre erosion, krävs både att platsen för brottet och metoden för att reparera är kända. En metod för att reparera inre erosion är genom att använda injektering och injektera hålutrymmet. Dock är kunskapen gällande vad för typ av injektering och hur den ska hanteras icke existerande i dagsläget. Det finns anledning att tro att ett härdande bruk inom en jordfyllningsdam, med en moränkärna, inte kommer samarbeta särskilt bra. På grund av det har ett bruk med icke-härdande egenskaper undersökt. Den här uppsatsen fokuserar på de geotekniska hållfasthetsegenskaperna för två liknande experimentella icke-härdande bruk. Ett med maximal kornstorlek på 2 mm benämnd som bruk 0/2 och ett med maximal kornstorlek på 4 mm, benämnd som bruk 0/4. Bruket består av natursand, kalciumkarbonat, vatten, bentonit, mjukgöringsmedel och skumdämpare. Bruken är utvärderade genom deras odränerade skjuvhållfasthet, vattenkvot, skrym- och torrdensiteten som har tagits fram från fallkorns-test och enaxiella trycktest (UCS). För att utvärdera brukens friktionsvinkel och dilationsvinkel tillsammans med styvheten (initiella och 50 %) har konsoliderat, dränerat triaxiala tests utförts. Tre test med varierande konsolideringstryck (50, 150 och 300 kPa) har utförts för båda bruk

Grouting is the injection of mixtures with high pressure into the voids, cracks, or pores that may exist in the soil. In the case of rock salt being present in the formations where the grouting is performed, studies on the effects of this salt presence on the freeze-thaw strength of the grout are rare in the literature. The Taguchi Method was used to assess the effect of rock salt on the freeze-thaw strength of grouts in this research (at 0, 50, and 100 freeze-thaw cycles). For the experimental design, a 3-parameter and a 4-level experimental design table were employed following the Taguchi Method. In the Taguchi Method, water/cement ratio (W/C), sand percentage (SP), and saturation percentage with rock salt (SPRS) were chosen as experimental parameters. The levels of these parameters were determined as 0.8-1.0-1.2-1.4; 0%-25%-50%–100%; and 0%-25%-50%–100%, respectively. The freeze-thaw strength of the prepared grout samples at 0, 50, and 100 cycles were determined. As a result of the experiments, it was determined that the strength of 50 cycles of grout samples increased by up to the 2nd level (25%) of SPRS. The 0 and 100 freeze-thaw strength decreased with the increase in SPRS. Pertaining to all prepared grout samples, freeze-thaw strength decreased when W/C increased and rose as SP increased in general.

Grouting is the injection of mixtures with high pressure into the voids, cracks, or pores that may exist in the soil. In the case of rock salt being present in the formations where the grouting is performed, studies on the effects of this salt presence on the freeze-thaw strength of the grout are rare in the literature. The Taguchi Method was used to assess the effect of rock salt on the freeze-thaw strength of grouts in this research (at 0, 50, and 100 freeze-thaw cycles). For the experimental design, a 3-parameter and a 4-level experimental design table were employed following the Taguchi Method. In the Taguchi Method, water/cement ratio (W/C), sand percentage (SP), and saturation percentage with rock salt (SPRS) were chosen as experimental parameters. The levels of these parameters were determined as 0.8-1.0-1.2-1.4; 0%-25%-50%–100%; and 0%-25%-50%–100%, respectively. The freeze-thaw strength of the prepared grout samples at 0, 50, and 100 cycles were determined. As a result of the experiments, it was determined that the strength of 50 cycles of grout samples increased by up to the 2nd level (25%) of SPRS. The 0 and 100 freeze-thaw strength decreased with the increase in SPRS. Pertaining to all prepared grout samples, freeze-thaw strength decreased when W/C increased and rose as SP increased in general.

The use of construction and demolition waste is an effective solution to mitigate their environmental impacts and avoid dispose in landfills. This paper aims to evaluate the use of fine recycled-concrete aggregate (FRCA) in grout mixtures used in soil nailing. Compressive strength tests on FRCA grout were carried out at different curing ages and interface shear strength was measured between soil and grout. Properties of a commonly used cement grout are compared with those of sand-cement grout and FRCA-cement grout. Although the FRCA grout shows a lower compressive strength compared to commonly used grout and sand-cement grout, its measured properties still meet the minimum standards requirements. The interface friction angle and adhesion of the FRCA exhibit higher values compared to those measured at the soil-soil interface. The grout mixtures evaluated in this study indicated that it is possible to use 1.126 kg of FRCA for each cubic meter of grout. The consumptions of cement and water were found to be 42% and 24% lower, respectively. This represents approximately 380 kg less of CO2 emissions into the atmosphere per cubic meter. The use of FRCA in soil nail grouting can be a sustainable alternative to reduce environmental impacts, cement consumption, and greenhouse gas emission. © 2021 American Society of Civil Engineers.

Prefabricated construction and requirements for reusing the particular structural element, request the application of a support joint realized with anchors. Besides demountability, the connection detail realized with anchors needs to satisfy all support conditions adopted during the structure design. This paper describes the behaviour of anchor shear connection. The connection slip was analysed concerning the grout material properties and the grout thickness. The parametric study was performed using Abaqus software to define the relationship between grout properties and thickness and the slip deformation for load levels corresponding to serviceability limit states.

In tunnel engineering one of the most important factors are the groundwater flow. To solve this problem a method called grouting is commonly used. In this study grout mixes are developed based on specific requirements for a deep shaft located next to a body of water. These circumstances require a grout with extraordinary penetrability and durability. During the excavation of a shaft, different groundwater pressures and fracture structures is going to be present. This creates conditions where different types of grouts are necessary. In order to develop grout, there are several factors that needs to be taken into consideration. Some of these are the cement properties, additive properties and amounts, water cement ratio, mixing regime, external physical impact etc. In this study several experiments were used to determine the properties of the grout mixes in order to fulfil the requirements needed for certain rock conditions. Three different cements and several additives have been used in different combinations in order to find the right mix. The first step of the experimental process is to do screening tests. The screening tests consists of penetrability, flow and density tests. After a grout passes these tests, several other tests are performed to ensure the right properties. In the beginning of the experiments, problems occurred with one of the cements which led us to suspect the quality of the cement. In order to ensure that the sources of error from lab equipment, different production dates, conditions of cements and additives are excluded several tests were performed. The test results of the cement did not improve regardless of the troubleshooting.When another cement type was tested the results immediately improved and passed the screening test. The test results from the new cements and additives led to further testing and development of two approved grout mixes. When another cement type was tested the results immediately improved and passed the screening test. Th, Vid tunnelbyggande är en av de största utmaningarna tätning av berget för att undvika vatteninträngning. Detta är viktigt av flera anledningar. Grundvatteninträngning kan resultera i en lokal grundvattensänkning som kan medföra förödande konsekvenser. Det kan leda till sättningar som i sin tur leder till skador på byggnader och även den befintliga växtligheten kan förstöras av en allt för stor grundvattensänkning. Det finns flera tekniska åtgärder till detta problem och ett exempel på detta är tätning med injekteringsbruk.Syftet med denna studie var att utveckla tre olika injekteringsbruk som har de egenskaper som krävs i schaktet vid Stadsgårdskajen. Egenskaperna som hade krav på att uppfyllas var penetrationsförmåga, sättningstid, sträckgräns, skjuvhållfasthet, rinntest, vattenseparation och densitet.Studien är i huvudsak byggd på det egna laborerade arbetet men har kompletterats med vetenskapliga rapporter där den viktigaste källan var Betonghandboken Material. För att få kunskap om de specifika materialen som användes i studien fanns tekniska datablad för respektive produkt.Resultaten visar hur olika cementtyper reagerar med olika kombinationer av tillsatser och vattencementtal. Tester genomfördes på tre olika typer av portlandcement varav två av dessa var sulfatresistenta. Tillsatserna som användes i studien var superplasticerare, accelerator, retarder och viskositetstabiliserare. Resultaten är uppdelade i VCT (vattencementtal) för respektive cementtyp.Några slutsatser av studien är att RHEOCEM 650 SR inte fungerade som förväntat. Detta sannolikt på grund av dålig cementkvalité. MasterRoc MP 650 och Injektering 30 gav betydligt bättre resultat och det är från Injektering 30 som de båda godkända mixarna utvecklades från. Ifall fortsatta studier hade genomförts hade en godkänd mix 1 utvecklats. Det hade även varit intressant att se hur de olika godkända mixarna fungerade i praktiken.

To fight increasing traffic in city centres, tunnelling can be used to move traffic under the surface of the busy city. However, to prevent damage to the surrounding buildings, the settlements induced by the tunnelling should be kept to a minimum. This thesis researches the influence of the TBM tail void and its grouting process on the settlements. To do so, the monitoring and TBM data from the North/South line in Amsterdam is used. The data of the settlements, grout pressures and grout volumes is searched for locations with sudden changes. For these locations, the development of the settlements as a function of the TBM movement is compared to find out if the changes in settlements are caused by the tail void. This turns out to be the case for half of the researched locations. Furthermore, the changes of the grout pressuresmeasured in the tail void, and the volume injected grout volume are compared for these locations. An increase in injected grout volume shows to decrease the settlements induced by the tail void, while the pressure does not show a correlation with the settlements. Because only one sensor was used for the pressuremeasurements, the grout pressures are then compared for all sensors in the tail void. Again, no correlation is found between the grout pressures and the settlements. A side step in the research shows the development of the grout pressures in the tail void. During the boring process the grout pressures fluctuate. During the boring and forward movement of the TBM the tail void is injected with grout and the grout pressures in the tail void increase. During the ring building phase, this grouting stops and the grout pressures start to dissipate. The amount of dissipation is influenced by the permeability of the surrounding soil. With the help of DIANA FEM software, the influence of the tail void on the total settlements is investigated. The calculations show that a different grouting behaviour caused a change of only 4mmin total settlements. Co, Geo-Engineering

The yearly installed percentage of offshore wind jacket substructures is rising. The most common installation method for a jacket structure nowadays starts by driving the foundation piles in the seabed through a pre-piling template. The jacket is then lowered on top until the legs are resting on the foundation piles through friction-based stopper connections. In order to rigidly fix the connection, grout is pumped into the annulus between the pile and leg. During the curing period of grout, generally taken as 24 hours, environmental loads cause the jacket to oscillate in various directions. As a result, the jacket leg will move relative to the foundation pile. This movement, which is called Early Age Cycling (EAC), can cause crack formation in the cured grout therefore decreasing the shear capacity of the connection. The DNV GL has restricted this relative movement to a conservative 1 mm within the first 24 hours due to a research gap on the subject. The strict regulation forces companies to use expensive EAC mitigation concepts of which the real effects are a debated issue. The objective of this research is to gain insight into the modelling approach and the magnitude of EAC movements and investigate how they can most efficiently be minimized. This is achieved by investigating three phases: 1) simulating a number of load cases on a global jacket model and extracting interface forces near the seabed, 2) using these interface forces to assess the EAC movement on a detailed pile-leg reference model with a full circular stopper 3) analysing this reference stopper by testing three modified configurations. These configurations are designed with respectively two, three and four brackets yielding the same contact area. A sensitivity study is then performed by increasing the contact area. The largest EAC movement within all models can be measured at the tip of the jacket leg. The location of this movement on the circumference of the leg varies based on th, European Wind Energy Masters (EWEM)

[Resumen] Según la Asociación Española de Fabricantes de Mezclas Asfálticas (ASEFMA), en 2018 se produjeron en España 16,1 millones de toneladas de mezclas asfálticas en caliente, lo que corresponde a una generación de 644.000 toneladas de filler de recuperación. Este residuo es parcialmente aprovechado por la propia industria, pero en un porcentaje reducido del 3-4%, siendo el resto enviado a vertedero. Este proyecto se centra en la búsqueda de un nuevo uso a dicho residuo, incorporándolo como sustituto del filler comercial en grouts de relleno de bloques de hormigón y analizando su comportamiento junto con otro residuo, el árido reciclado. Se diseñó un programa experimental dividido en dos fases: la primera dedicada a la creación y prueba, tanto en estado en fresco como en endurecido, de grouts con distintos porcentajes de filler de recuperación y presencia o no de árido reciclado. En la segunda fase, se introdujeron el grout de control y el grout con mayor cantidad de residuos, en bloques de hormigón convencionales, y bloques con una sustitución del 100% del árido por ceniza de fondo de carbón para analizar su comportamiento. Los resultados obtenidos muestran que, aun produciendo un descenso de las resistencias y trabajabilidad en el grout, la incorporación del filler de recuperación con árido reciclado mejora el comportamiento del conjunto de bloque más grout frente a esfuerzos de compresión, elevando las resistencias de estos., [Resumo] Segundo a Asociación Española de Fabricantes de Mesturas Asfálticas (ASEFMA), en 2018 producíronse en España 16,1 millóns de toneladas de mesturas asfálticas en quente, o que corresponde a unha xeración de 644.000 toneladas de filler de recuperación. Este residuo é parcialmente aproveitado pola propia industria, pero nunha porcentaxe reducida do 3-4%, sendo o resto enviado a vertedeiro. Este proxecto céntrase na procura dun novo uso ao filler de recuperación, incorporándoo como substituto do filler comercial en grouts de recheo de bloques de formigón e analizando o seu comportamento xunto con outro residuo, o árido reciclado. Deseñouse un programa experimental dividido en dúas fases: a primeira dedicada á creación e proba, tanto en estado en fresco como en endurecido, de grouts con distintas porcentaxes de filler de recuperación e presenza ou non de árido reciclado. Na segunda fase, introducíronse o grout de control e o grout con maior cantidade de residuos, en bloques de formigón convencionais, e bloques cunha substitución do 100% do árido por cinza de fondo de carbón para analizar o seu comportamento. Os resultados obtidos mostran que, aínda producindo un descenso das resistencias e traballabilidad no grout, a incorporación do filler de recuperación con árido reciclado mellora o comportamento do conxunto de bloque máis grout fronte a esforzos de compresión, elevando as resistencias destes., [Abstract] According to the Spanish association of manufacturers of asphalt mixtures (ASEFMA), in 2018 16,1 million tons of hot asphalt mixtures were produced in Spain, which corresponds to a generation of 644,000 tons of recovery filler. This waste is used by the industry itself, but in low percentages between 3 and 4%, the rest is sent to landfills. This project focuses on searching for a new application for this waste, incorporating it into masonry grouts as a substitute for the commercial filler, and analyzing its behavior with another waste, the recycled aggregates. An experimental program was designed, divided into two phases. The first one created with the purpose of testing different grouts with different percentage of recovery filler and recycled aggregates. The second one, the grout used as control in phase one, and the grout with the largest amount of wastes was used to fill two types of concrete blocks: conventional ones, and blocks made with bottom coal ash instead of fine aggregates. The results show that, even though the compressive strength of the grout decreases with the addition of the recovery filler and the recycled aggregate, the combination between the two materials acts homogeneously and got higher compressive strength than the control ones.

We investigate the ultrasonic transport properties of such an idealised fracture whose 100 µm aperture is about 0.02 the wavelength, and filled with various fluids flowing under external forcing. As the artificial fracture is made of two solid and parallel walls separated by a thin fluid layer, we use the thin fluid layer concept to study the compressional (P-) wavefield transmitted across and reflected off the fracture, with no mode-conversion considered. We demonstrate that air and various fluids (water, grouts of varied w/c – water to cement ratio) can be distinguished when injected into the fracture, both at atmospheric pressure or under over-pressure as done in real grouting cases in the field. Then, using an analytical solution, we verify our experimental data and predict the results that can be obtained with a different fracture aperture. Our results illustrate that replicating such ultrasonic measurements both in space and time would allow successfully monitoring the grout propagation within an artificial fracture., QC 20161117

Corrosion failure of post-tension tendons with pre-packaged thixotropic grout was documented in Florida Bridges in less than 10 years of service. Analysis of deficient grout in Florida post-tensioned (PT) bridges where severe corrosion developed indicated enhanced sulfate ion concentration, high pore water pH, enhanced moisture and low chloride content. The corrosion wasn’t consistent with the conventional causes of steel corrosion such as bleed water accumulation in grout void spaces, chloride contamination and pore water carbonation. Corrosion development was associated with deficient grout with enhanced sulfate levels. However, limited information is available on the corrosion behavior of PT strand in grout materials with enhanced sulfate content. Review of the technical literature has not shown consistent evidence of the role of sulfate ions in the corrosion of steel in solution and in hydrated cementitious material. In this research, the role of sulfates in cementitous materials was examined including identifying practical limits for sulfates in grout materials. Laboratory samples were created with 15% and 20% excess water to enhance deficient grout materials and included enhanced sodium and chloride content. Enhanced sulfate and chloride ion presence was thought to provide aggressive corrosion condition of steel in segregated grout. Testing was intended to differentiate the corrosion of steel in pore water condition of deficient grout.

One of the most important parameters in the grouting of rock fractures is the applied pressure. This produces the driving force on the Bingham group material that causes it to penetrate the fracture. However, deciding the optimum pumping pressure is challenging. Using too high a pressure not only causes the grout to spread beyond the desired area, but, if it exceeds the minimum in situ stress in the rock mass, may also cause jacking of the fractures. This may lead to uncontrolled uplift. With a lower grout pressure, this "ultimate state" (jacking) can be avoided, although the pressurized grout still may induce smaller elastic deformations during pumping, and these may become irreversible when the grout has hardened. In previous studies, various theoretical approaches to distinguish the onset of these elastic and non-elastic deformations have been described and evaluated. However, the merits and disadvantages of theoretical approaches in general have been questionable. In the current study, the basic mechanism of elastic jacking is described, and its negative consequences are analyzed and quantified. These are the prolongation of grouting time, and the reduction in sealing efficiency. The role of an increased grouting pressure is evaluated by considering its positive effect in improving the penetrability and comparing this with the potential negative consequences. Case studies from two projects (the THX and Citybanan projects) are studied to examine the efficiency of the work that was carried out on site. The results indicate a high-applied pressure can have negative effect on the grouting procedure, and that this effect is significant in fractures situated in weak rock at shallow depth. It is concluded that unwanted fracture deformations and their negative consequences can be eliminated by defining appropriate stop criteria in advance of grouting, and confirming their suitability during pumping by the use of theoretical approach presented here. In general, this will, QC 20150602

Peat commonly occurs as extremely soft, wet, unconsolidated surface deposits that are integral parts of wetland systems. The increasing growth of the population leads to the need to use peat land for development purposes. Cement is widely used for the stabilization of peat by the deep mixing method. This article describes a laboratory study on the effects of different additives on the settlement of fibrous peat. The effect of sodium silicate, ordinary Portland cement, and kaolinite on the settlement of treated peat by cementsodium silicate grout is investigated through a Rowe Cell consolidation test. At the end of this study, it is shown that increasing the amount of sodium silicate (within 2.5%), cement, and kaolinite in treated peat improves the settlement of fibrous peat much better than conventional binders like pure cement.

Culturally significant monuments made of weathered siliceous stone often display sub-surface condition issues such as cracks and voids. These issues require grouts that are ideally compatible with the composition and properties of the substrate. Based on the successful application of ethyl silicates as consolidants in recent literature, this study examines possible formulation pathways for the development of a grout incorporating ethyl silicate. Tetraethylorthosilicate (TEOS), dibutyltin dilaurate (DBTL) as a catalyst, silicone oil (PDMS), various grades of ground quartz, sepiolite, and hollow glass spheres were used in differing concentrations to create samples. These were visually and physically assessed on workability, separation, shrinkage, cracking, strength, and flexibility. Quantitative analysis was performed on selected formulations using UV-Vis-NIR reflectance spectroscopy in coordination with a weight loss experiment to investigate kinetics, dynamic mechanical analysis (DMA), and scanning electron microscopy (SEM). Successful formulations tended to include oligomeric TEOS, crushed quartz of mixed grades, sepiolite powder, and PDMS, and show promise for future investigations.

The expansion of the use of geothermal heat pumps makes the study of their performances a keystone in their development. Several parameters are crucial to design properly a geothermal heat pump. Comparing the theoretical characteristics of a system with the actual ones one the field is part of its understanding. This Master thesis gives a closer look for determining from filed data two central parameters, the borehole thermal resistance and the ground thermal conductivity, using a newly developed technique called Distributed Thermal Response Testing (DTRT). These calculations are applied to a U-pipe heat exchanger installed in a private household. From these two parameters, it is possible to estimate the thermal conductivity of the filling material inside the borehole and thus estimate its influence on the performances of the system. Three grouting material are studied here and theoretical values are compared with experimental value in order to try to get a picture of the inside of the borehole. This thesis provides a picture of the actual thermal parameters of the studied borehole, which clearly reveals the influence of the grouting material in each layer. It is also noticed that the laboratory value of the grout thermal conductivities varies when comparing with theoretical values or manufacturer data. The lack of understanding of the actual drying state of the grouts inside the borehole may by one reason why.

In the last fifteen years, Tekseal high yield foaming group ore pass plugs that could later be easily removed, have been poured above chute maintenance areas providing protection from high energy rock impact and isolating workers fom the hazard. Construction and removal methods awill be briefly explained. Since it is not economically feasible to investigate the problem of ore pass plug impact response using full-scale experimental studies, this paper presents a combined four-stage approach that includes (1) laboratory testing to investigate the mechanical behaviour of the high-yield foaming grout; (2) high-precision impact testing of reduced-scale models of ore pass plugs; (3) high-fidelity physics-based numerical model calibration using experimental data; and (4) full-scale modelling of mine ore pass plugs using calibrated material models. To calibrate numerical models, threeone--metre diameter steel pipes filled with Tekseal high yield foaming grout were tested with falling steel projectiles of different shapes. Impact tests provided data on the depth of penetration and size of the craters formed by the projectiles. Numerical models were calibrated by optimising the material parameteres and modelling techniques to provide the best match withthe experimental results. Full-scale numerical models of ore pass plugs were developed for typical ore pass dimensions and subjected to impact events by falling rock projectiles. The proposed approach has allowed investigating energy absorbing characteristics of ore pass plugs to further predict and increase understanding of their capacity to withstand high-speed impacts by large falling projectiles.

Manitoba Hydro owns and operates 12 river hydroelectric generating stations ans two major control structures. The structures control the flow of water almost exclusively with gate wheels. It is important for the roller paths to remain true to allow uniform distribution of the hydraulic load on the gates to the gate wheels. Manitoba Hydro is currently replacing the distorted steel roller paths at its MacArthur Generating Station. The purpose of this study was to evaluate the physical properties of high strength proprietary grouts to determine their adequacy for use beneath new roller paths of water control gates which have unusual spacial constraints. Two full size mockups of a portion of an existing guide, with a steel overlay, were utilized in the experimental study. To investigate the stress-strain distribution in the mockup under specific loading condition, strain gauges were installed on both of the web sides of the embedded steel I-beam: one group of gauges was located just below the flange, the others were located along the mid-hight of the beam web. Force gauges were inserted to measure the pressure between the thin grout layer bottom and the top of the embedded I-beam. A special LVDT (linear variable differential transducer) assembly was made to measure the maximum displacement of grout layer. Mockup samples were subjected to static and cyclic loading procedures at two designated loading points. The grout cylindrical creep tests were conducted at the same time. It included tests at room temperature and at the elevated temperature of 50°C. The initial sustained load was 50% of the ultimate compression strength of the grout cylinder (3"x6"). Once the creep development was observed to become constant, the sustained load was raised up to 70% of ultimate strength and held constant until the end of the test. The test results indicate that the strength of the proposed grouting material is adequate to resist the required load, both statically and cyclically. Tempera

To improve the performance of the conventional nail laminated bridge deck, three generations of innovative decks have been developed during the last three decades: (a) the stress laminated wood deck, (b) the stressed log bridge, and (c) the grout laminated wood deck. The grout laminated wood deck, the most recent wood deck, consists of trimmed logs interconnected with internal grout cylinders, in compression or tension. Previous research has shown that the grout cylinders have superior load distribution characteristics, but the cost of trimming the treated logs was found to be relatively high. Recently, research has been conducted to develop the next generation of the bridge wood decks, called the anchored log decks. The anchored log deck, meant for use as decking of steel girder bridges, consists of untrimmed discarded utility timber poles which have been treated with preservatives. The logs are held together by means of unstressed transverse proprietary Cintec anchors. The anchors consist of stainless steel rods encased in grout cylinders. Panels, each comprising of 5 to 6 logs, are preassembled to fit on a flatbed trailer for shipping. The smooth wearing surface over the log deck is provided by longitudinal sawn timber planks, with high-density foam filling the gap between the logs and the planks. The panels are inter-connected through inclined anchors passing through adjacent logs. At the University of Manitoba, an anchored log deck with five preassembled panels was constructed and tested to failure at several locations under both static and fatigue loads. The test results have shown that anchored log decks have the potential of being economical preassembled decks for steel girder bridges.

Peat is often referred as problematic soil due to its high compressibility, low shear strength, and high water content. However, high surface electrical charge and high cationic exchange capacity of peat makes it a good source for transporting and/or exchange with cations. In this study, a series of batch test is performed to find out the effect of strength improvement of portland cement mixed with the peat. Then, the feasibility of injecting cement electrokinetically into peaty soil environment has been assessed. The microstructure of the treated peat was also investigated by scanning electron microscopy and energy-dispersive X-ray spectrometer analysis. The results showed that the undrained shear strength, pH, and water content of treated peat are affected after electrokinetic treatment. Because of the electrokinetic process, the undrained shear strength was improved to maximum of 308 % and minimum of 30 % in the normalized distance of 0.1 and 0.9 from anode, respectively. The pH was also increased to the maximum of 8 in the normalized distance of 0.1 and 0.9 from the anode. However, the water content was reduced after 7 days of electrokinetic processing.

Post-tensioned bridge construction has become increasingly popular and financially competitive with traditional prestressed concrete and steel plate girder bridges. Unfortunately, Indiana has experienced several construction-related problems in the few post-tensioned structures built, some of which have caused significant long-term durability concerns. Indiana’s problems have generally been attributed to a lack of a standard set of specifications for post-tensioned construction as well as inexperience and inadequate training of contractors and inspectors. These types of issues, however, were once more prevalent throughout the industry and much work has been accomplished in recent years to address these issues. This research program had two primary objectives: (1) to improve the quality of post-tensioned bridge construction in Indiana and (2) to provide the State with more confidence when using this type of construction. First, past problems related to post-tensioned construction were identified, and for each, case studies were conducted. Each case study includes an overview of the bridge, a summary of the problems related to post-tensioning, and possible sources and remedies to those problems. Next, a standard post-tensioning construction specification was developed. The specification addresses problems specific to Indiana which were found in the case studies and common problems experienced in the industry as a whole. Specifically, the specification addresses industry standards of practice, requirements for certification and experience of personnel, and proper testing and sampling procedures. In addition, specific recommendations are provided for training programs and certification of INDOT construction personnel to ensure they are properly trained to inspect post-tensioned construction.

Significant wear in orepasses particularly in the brow and chute areas is proportional to the tonnage throughput with increased wear associated with running orepasses empty. During planned shutdowns it may be necessary to isolate maintenance crews from objects falling from orepasses. In the last 15 years grout orepass plugs that can later be easily removed have been poured above chute maintenance areas. These provide protection from high energy impact and isolating workers from the hazard. Construction and removal methods will be briefly explained. Since it is not feasible to investigate the problem of orepass plug impact response using full-scale experimental studies, this paper presents a combined three-stage approach that includes: 1. High-precision impact testing of reduced-scale models of orepass plugs. 2. High-fidelity physics-based numerical model calibration using experimental data. 3. Full-scale modelling of mine orepass plugs using calibrated material models. To calibrate numerical models, three 1 m diameter steel pipes filled with Tekseal high yield foaming grout were tested with falfing steel projectiles of different shape using the High-Capacity Impact Testing Facility at the University of Wollongong. Impact tests provided data on the depth of penetration and size of the ci6ters formed by the projectiles. Numerical models were calibrated by optimiSing the material parameters and modelling techniques to match with the experimental results. . Full-scale numerical models of orepass plugs were de veloped for typical orepass dimensions and subjected to impact events by falling rock projectiles. The proposed approach has allowed investigating energy absorbing characteristics of orepass plugs to further predict and increase understanding of their capacity to withstand high-speed impacts by large fa lling projectiles. This research will enable better understanding of orepass plug performance during high energy events and provide f urther engineering definition

Detta examensarbete har gjorts i syfte att få fram förankringslängder till ett bergförankrat vindkraftverk. Målet med examensarbetet har varit att få fram längder på förankringstag och en prövning av flera olika stagvarianter har gjorts. Det dimensionerande momentet och egentyngden på vindkraftverket har tagits från ett tidigare projekt beläget i Solberg. Dessa krafter har fördelats ut till stagen och förankringslängder har tagits fram. De delar som har hanterats i rapporten utöver dimensioneringen är stagvarianter, borrning av stag, injekteringsbruk och provdragning. En bottenplatta i form av en oktogon har använts i dimensioneringsprocessen. Stagen har placerats i en cirkulär form i ett lager. Tre olika metoder har använts för att få den dimensionerande längden på förankringen. De tre metoderna hanterar: Vidhäftning mellan berg och injekteringsbruk Vidhäftning mellan stål och injekteringsbruk Bergkonsmetoden En analys har gjorts mellan dessa. För att lösa problemet har en litteraturstudie i olika böcker och eurokoder gjorts. Intervjuer med personer från olika företag med anknytning till förankringar har varit en bra grund till examensarbetet. Efter avslutade litteraturstudier har formler för beräkning av problemet tagits fram och fyra excel-modeller har upprättats för beräkning av förankringslängder. Ett beräkningsexempel på ett stag från Pretec har gjorts och förankringslängder har tagits fram. I resultaten har dragkraften i varje stag varierat mellan 1725 – 3747 kN, detta kan ses i tabell 6. Förankringsdjupet för de olika lastfallen varierar mellan 3 – 10 meter. De slutsatser som har gjorts är att förankringslängden ökar med sprucket berg då vidhäftningen är försämrad och att förankringslängden ökar med ökad påfrestning hos stagen. Metoden där förankringslängden bestäms med hjälp av bergkonsmetoden kan uteslutas vid homogent berg., This master’s dissertation has been made in order to gain a deeper knowledge of how to design anchors to a wind turbine on rock. The goal of the master’s dissertation has been to produce lengths of anchors and trials of several different anchors have been made. The design overturning moment and the weight of the construction that occur in wind turbine has been distributed to the anchors and anchorage lengths have been calculated. The areas that have been handled are anchor variants, drilling, grouting and testing of the anchorage. A bottom plate in the form of an octagon has been used in the design process. The anchors have been placed into a circular shape in one layer. Three different methods of solution were used to design the length of the anchorage. The three different methods manage: Bond between rock and grout Adhesion between steel and grout Rock cone method An analysis has been made between them. To overcome this, a literature study in various books and Eurocodes have been made. Interviews with people from various companies related to the anchorages have been a good foundation for this master’s dissertation. After completing literary studies, the formulas for calculating the problem has been developed and several Excel models have been established for calculating the anchorage length. The results of the pulling force varied between 1725 - 3747 kN. Anchor lengths that have been calculated vary between 3-10 meters. A calculating example of an anchor from Pretec has been made and the anchorage length has been produced. The conclusions are that the anchor length increases with fractured rock where the adhesion is impaired and that the anchoring length increases with increased tension in the anchors. The method in which the anchor is determined by the length of the rock cone is very conservative and may be omitted.

Populärvetenskaplig sammanfattning: Ett geoenergisystem består av ett eller flera borrhål, energibrunnar, som via värmeväxlare är kopplade till en värmepump. I en del fall är det önskvärt att borrhålen återfylls. Detta görs för att förhindra spridning av föroreningar från ytan och mellan olika vattenförande marklager som borrhålet kan penetrera. Utomlands görs detta regelbundet och omfattande forskning har bedrivits på området. I Sverige saknar dock branschen klara riktlinjer och tillräcklig kunskap om hur och med vad det ska göras. Den här litteraturstudien är en förstudie till en handledning om hur återfyllning ska ske. Syftet är att ge en bred överblick över forskningsläget och konventionerna främst i Sverige, USA och Tyskland med fokus på vilka material man använder sig av och varför, samt vilken teknik som används. Ett försök att utreda hur bentonit reagerar på frysning och på salt grundvatten har också gjorts. Studien visar att när borrhål återfylls i Tyskland och USA görs det nästan uteslutande genom tryckinjektering nerifrån och upp via ett påfyllnadsrör som sänks ner tillsammans med kollektorslangarna. Utifrån den undersökta litteraturen har slutsatsen nåtts att det främst är cementbaserade och bentonitbaserade material med olika tillsatser som används utomlands. Tillsatserna förstärker bland annat materialens förmåga att täta borrhålet, deras värmeledningsförmåga, frystålighet och injekterbarhet. Bentonit är en naturligt förekommande lera som har förmågan att ta upp stora mängder vatten och svälla flera gånger sin egen volym. Den främsta svagheten hos de bentonitbaserade material är en dålig motståndskraft mot uttorkning som orsakar stora volymförluster och kraftig försämring av värmeledningsförmågan. Dessutom har materialen ofta lägre värmeledningsförmåga från första början än de cementbaserade. Nackdelen med de cementbaserade materialen är istället att de stelnar i borrhålet. Därmed saknar de generellt förmågan att upprätthålla en kontakt med kollektorsl, A shallow geothermal energy system consists of one or several boreholes connected to a heat pump through borehole heat exchangers. In some circumstances it’s desirable that the boreholes are grouted. This is carried out primarily to reduce the risk of contaminants being transported from the surface and between aquifers that the borehole penetrates. In the USA and Germany grouting is regularly performed and a substantial amount of research has been conducted on this topic. In Sweden the industry lacks clear guidelines and enough knowledge about how and with what to grout. This literature study is an introductory investigation for a manual on how this should be done. Its purpose is to take a broad look at the current research state and conventions primarily in Sweden, Germany and the USA focusing on what materials and techniques are employed. An attempt at describing how bentonite is affected by freezing and saltwater has also been made. When boreholes are filled in Germany and the USA it’s almost exclusively done by pressure grouting through a tremie pipe from the bottom up. The pipe is lowered into the hole along with the borehole heat exchangers. The investigation concludes that cement- and bentonite based materials with additives are mainly used. The additives enhance, among other things, the materials’ thermal conductivity, bond strength to the heat exchanger, resistance to freezing and pumpability. A cement based grout generally hardens up into a solid material in the borehole. This prevents it from keeping a tight bond with the heat exchanger when the pipe contracts upon cooling during heat extraction from the borehole. This increases the hole’s permeability and hinders the transfer of heat between formation and brine fluid which reduces the system’s efficiency. The primary weakness of bentonite based materials is their poor resistance to dehydration which causes large volume losses and a major reduction in thermal conductivity. In addition, they also generally, Ett geoenergisystem består av ett eller flera borrhål, energibrunnar, som via värmeväxlare är kopplade till en värmepump. I en del fall är det önskvärt att borrhålen återfylls. Detta görs för att förhindra spridning av föroreningar från ytan och mellan olika akvifärer som borrhålet kan kortsluta. Utomlands görs detta regelbundet och omfattande forskning har bedrivits på området. I Sverige saknar dock branschen klara riktlinjer och tillräcklig kunskap om hur och med vad det ska göras. Den här litteraturstudien är en förstudie till en handledning om hur återfyllning ska ske. Syftet är att ge en bred överblick över forskningsläget och konventionerna främst i Sverige, USA och Tyskland med fokus på vilka material man använder sig av och varför, samt vilken teknik som används. Ett försök att utreda hur bentonit reagerar på frysning och på salt grundvatten har också gjorts. Studien visar att när borrhål återfylls i Tyskland och USA görs det nästan uteslutande genom tryckinjektering nerifrån och upp via ett påfyllnadsrör som sänks ner tillsammans med kollektorslangarna. Utifrån den undersökta litteraturen har slutsatsen nåtts att det främst är cementbaserade och bentonitbaserade material med olika tillsatser som används utomlands. Tillsatserna förstärker bland annat materialens vidhäftning till kollektorslangen samt deras termiska konduktivitet, frystålighet och injekterbarhet. De cementbaserade materialen stelnar generellt i borrhålet. Därmed förlorar de förmågan att följa kollektorslangen som drar ihop sig då köldbärarens temperatur sjunker när värme utvinns ur borrhålet. Detta ökar borrhålets permeabilitet och hindrar värmeöverföringen mellan formation och köldbärare vilket försämrar systemets funktion. Den främsta svagheten hos de bentonitbaserade material är en dålig motståndskraft mot uttorkning som orsakar stora volymförluster och kraftig försämring av dess termiska konduktivitet. Dessutom har materialen ofta lägre termisk konduktivitet än de cementbaserade. Baserat

Filtration of cement-based grout during penetration through fractures in rock is an important issue while sealing the rock around tunnels. Whether a type of grout could be designed to penetrate a fracture of a certain aperture without filtration is an interesting question that needs to be further investigated. This study examines the question of whether grout penetration can be measured using our designed measuring method as well as which factors and processes influence the penetrability and filtration of the grout. The penetration and filtration of grout are complex processes influenced by many factors such as the grain-size curve of the cement, hydration and flocculation, pressure, grain concentration, and the geometry of constriction. The measured results were in agreement with the predicted results, indicating that the filtration process in the given geometry describes correctly., QC 20120208

Partially grouted wider reinforced masonry wall, built predominantly using face shell bedded hollow concrete blocks, is an economical structural system and is popularly used in the cyclonic areas; its out-of-plane response to lateral loading is well understood, unfortunately its inplane shear behaviour is less well understood as to the effect of partial gouting in intervening the load paths within the wall. For rational analysis of the wall clarification is sought as to whether the wall acts as a composite of unreinforced panels and reinforced cores or as a continuum of masonry embedded with reinforced at wider spacing. This paper reports the results of four full scale walls tested under inplane cyclic shear loading to provide some insight into the effect of the grout cores in altering the load paths within the wall. The global lateral load - lateral deflection hysteric curves as well as local responses of some critical zones of the shear walls are presented.

Partially grouted wider reinforced masonry wall, built predominantly with the use of face shell bedded hollow concrete blocks, is adopted extensively in the cyclonic areas due to its economy. Its out-of-plane response to lateral pressure loading is well definied; however its in-plane shear behaviour is less well understood, in particular it is unclear how the grouted reinforced cores affect the load paths within the wall. For the rational design of the walls, clarification is sought as to whether the wall acts as a composite of unreinforced panels surrounded by the reinforced cores or simply as a continuum embedded with reinforcement at wider spacing. This paper reports four full scale walls tested under in-place cyclic shear loading to provide some insight into the effect of the grout cores in altering the load paths within the wall. The global lateral load - lateral deflection hysteretic curves as well as the local responses of some critical zones of the shear walls are presented. It is shown that the aspect ratio of the unreinforced masonry panels surrounded by the reinforced grouted cores within the shear walls have profound effect in ascertaining the behaviour of the shear walls.

This report presents the results of blast load resistance testing of masonry walls that minimally meet applicable Unified Facilities Criteria (UFC) reinforcement requirements. The testing and analyses presented in this report involved partially-grouted (1) 6-inch, (2) 8-inch, and (3) insulated clay brick veneer (cavity wall) concrete masonry test panels. Three blast load experiments were conducted; each experiment tested one each of the three test panel designs (nine test panels total). The impulse loading to the panels varied significantly between each of the three experiments. Failure mechanism observations were made using interior and exterior high-speed videos that captured the response of each panel. A post-test forensic investigation was also conducted after each experiment to further explore and document the ultimate response of each test article. Dynamic deflections were captured and the responses were compared to blast analysis codes used for masonry design., Prepared in collaboration with Black & Veatch, Federal Services Division, Webb City, MO; University of Missouri, Department of Civil and Environmental Engineering, Columbia, MO; Air Force Civil Engineering Support Agency, Tyndall AFB, FL; and U.S. Army Engineer Research & Development Center, Vicksburg, MS.

The grouting results for a tunnel at a depth of 450 min crystalline rock at Aspo HRL were studied. The aims were to investigate whether the methodology used resulted in a successful grouting design and producing a sufficiently dry tunnel, and whether grout penetration and inflow into the finished tunnel corresponded to the predictions. An analysis was made of data from an original cored borehole, drilled before the tunnel was constructed and mapped thoroughly with regard to fractures and transmissivities. The predicted inflow into the tunnel was calculated and found to be four times higher than the measured inflow. The latter was 51/min a long the 70 m tunnel, considered to be a good result at the current depth. New cored control boreholes were drilled along a section of the tunnel. The inflow positions and quantities in these holes, and the positions of grout found in the corresponding cores, were compared with the data from the original borehole. It was found that at the predicted positions of larger fractures, grout was observed and there was no inflow, showing that these had been successfully sealed. At the predicted positions of small fractures, no grout was visible in the cores, and small inflows showed that the grout had not sealed these fractures. The results indicated that cement-based grout successfully sealed fractures down to a hydraulic aperture of about 50 mm but not below 30 mm. This concurs with the initial design aimed at sealing fractures larger than 50 mm., QC 20100525

Behind the tunnel boring machine (TBM) the rings form a tunnel lining that is embedded in grout and soil. The TBM exerts a normal force, a bending moment and a shear force on the lining. The tunnel rings behind the TBM experience a load through the grout, ground and ground water, but the ground also acts as a support medium. A ring that has just left the TBM floats in the fluid grout that has hardly any stiffness and offers resistance to tunnel displacements due to downward grout flow. Furthermore, resistance is offered by force transfer to the TBM and the adjacent rings of the tunnel lining and the hardened grout further down the tunnel. The rings thus have to cooperate to create equilibrium. This cooperation is called beam action. The focus of the research of COB-committee F512 was aimed at the beam action behind the TBM during the construction phase of the Boortunnel Groene Hart (bored tunnel in the Groene Hart in the Netherlands). Important issues in the research were the displacements and deformations of the tunnel, stresses in the tunnel lining and the grout pressure at the exterior of the tunnel tube.

Behind the tunnel boring machine (TBM) the rings form a tunnel lining that is embedded in grout and soil. The TBM exerts a normal force, a bending moment and a shear force on the lining. The tunnel rings behind the TBM experience a load through the grout, ground and ground water, but the ground also acts as a support medium. A ring that has just left the TBM floats in the fluid grout that has hardly any stiffness and offers resistance to tunnel displacements due to downward grout flow. Furthermore, resistance is offered by force transfer to the TBM and the adjacent rings of the tunnel lining and the hardened grout further down the tunnel. The rings thus have to cooperate to create equilibrium. This cooperation is called beam action. The focus of the research of COB-committee F512 was aimed at the beam action behind the TBM during the construction phase of the Boortunnel Groene Hart (bored tunnel in the Groene Hart in the Netherlands). Important issues in the research were the displacements and deformations of the tunnel, stresses in the tunnel lining and the grout pressure at the exterior of the tunnel tube. The research consisted of the following phases: 1. Execution of predictions of the vertical displacements of an escape shaft in the planned route of the tunnel; 2. Composition of a measuring plan, placement of the measuring instruments, execution of the measurements and composition of the measuring reports; 3. Assessment and check on the measurement results; 4. Evaluation of the measurement results by means of modelling; 5. Composition of the final report. The executed predictions (phase 1, see above) forecasted only small displacements and thus only little beam action was expected to occur. Therefore it was decided to aim the research at beam action in the tunnel behind the TBM. Beam action in the tunnel is researched by carrying out several measurements: • displacements and tilt angles of the lining; • ovalisation of the lining; • strains in de tunnel segments

How to safely dispose of wastes from producing nuclear weapons has been an ongoing issue. The most radioactive portion of these wastes is stored in underground tanks at Department of Energy (DOE) sites in Idaho, South Carolina, and Washington State. There have been concerns about soil and groundwater contamination from some of the tanks that have leaked. DOE proposed to remove the pumpable liquid waste, classify the sludge-like remainder as waste incidental to reprocessing, and seal it in the tanks with a cement grout. DOE has argued that closing the tanks in this manner would be a cost-effective and timely way to address environmental risks. Questions were raised as to how much waste would be left in the tanks and whether the grout would contain the waste and prevent leaks. After considerable debate, the 108th Congress included provisions in the Ronald W. Reagan National Defense Authorization Act for FY2005 (P.L. 108-375) authorizing DOE to grout some of the waste in the tanks in Idaho and South Carolina. Congress did not provide such authority in Washington State. This report provides background information on the disposal of radioactive tank waste, analyzes the waste disposal authority in P.L. 108-375, discusses the implementation of this authority, and examines relevant issues., CRS Report for Congress

The U.S. military must have the ability to rapidly deploy troops and equipment anywhere in the world as part of a contingency operation. Recent military operations have highlighted the critical need for rapid repair procedures and materials for military use on substandard, in-theater airfields. The U.S. Army Engineer Research and Development Center is currently addressing these problems through a 6-year demonstration-based research and development program called JRAC (Joint Rapid Airfield Construction). This study involves the development of a method using rapid setting grouts and recycled concrete pavement (RCP) to repair portland cement concrete pavements. A laboratory study was conducted to evaluate material properties in order to gain an understanding of expected field performance. Eight full scale repairs were constructed using two rapid setting grouts, two types of equipment, and two concrete slabs. The repairs were successfully trafficked with simulated C-17 aircraft wheel loads to verify the structural capacity and, ultimately, the procedures., The original document contains color images.

Praktijkonderzoek Randstadrail: in dit rapport worden 3 metingen uitgewerkt: Overzicht metingen: Het is de bedoeling om drie verschillende type metingen uit te voeren, namelijk: Type meting Doel meting: - Gronddrukmeting - Meten van de belastingtoename in de Holocene kleilagen net buiten de groutschil als gevolg vanconsolidatie van kleilagen en door autonome zakkingen. - Groutdrukmeting - Meten groutdrukken in vloeibare toestand. - Groutdrukmeting met grotere platen - Het verkrijgen van inzicht in krachten op de tunnellining tijdens en na het verharden van het grout. Alle metingen vinden plaats net buiten de tunnellining danwel net buiten de groutschil. Voor alle metingen geldt dat ze zo snel mogelijk na het passeren van de TBM dienen te worden gestart, op het moment dat het grout nog vloeibaar is. Globaal principe installatie meetinstrumenten Alle metingen vinden plaats net. buiten de tunnellining dan wel net buiten de groutschil. Het grote verschil zit in het moment van installatie van de meetinstrumenten. De groutdrukopnemers en Hashimoto-platen worden reeds op de bouwplaats of in de startschacht op/in de tunnelsegmenten geïnstalleerd, vervolgens worden de segmenten door de tunnel richting TBM vervoerd en de ring wordt ingebouwd, waarmee tegelijkertijd ook de meetinstrumenten worden geplaatst. Na het plaatsen van de tunnelring dienen enkel de meetinstrumenten op een datalogger te worden aangesloten.

How to safely dispose of waste from the production of nuclear weapons has been a longstanding issue. The most radioactive of these wastes are stored in underground tanks at Department of Energy (DOE) sites in Idaho, South Carolina, and Washington state. There have been concerns about soil and groundwater contamination, as some of the tanks are known or suspected to be leaking. DOE proposed to pump out the liquid waste, classify the sludge-like remainder as waste incidental to reprocessing, and seal it in the tanks with a cement grout. DOE argues that closing the tanks in this manner would be a cost-effective and timely way to address environmental risks. Questions have been raised as to how much waste would be left in the tanks, and whether the grout would contain the wastes and prevent leaks. After considerable debate, Congress included provisions in Section 3116 of the Ronald W. Reagan National Defense Authorization Act for FY2005 (P.L. 108-375) that authorize DOE to grout some of the tank wastes in place in Idaho and South Carolina, subject to certain criteria, state approval, monitoring by the Nuclear Regulatory Commission, and appropriations by Congress. The law does not provide such authority in Washington state. This report provides background information, analyzes the waste disposal authority in Section 3116, and examines potential implications for environmental cleanup., CRS Report for Congress

Numerical modelling is extensively used in civil and mining engineering applications because of cost and risk problems associated with different experimental studies. In this study, the effect of resin thickness was evaluated in bolt-grout-concrete interaction and bending behaviour of a fully grouted bolt installed across joints in post failure region. Tests were conducted in 20 and 40 MPa concretes, and modelling simulations were made, using ANSYS version 8.1, to include both with and without different pretension loads. It was found that in all resin thickness, both the strength of the concrete and bolt pretension had major influences on the shear resistance and shear displacement of the reinforced medium. Also it was found that the strength of the surrounding concrete is more important than that of the grout thickness in both the shear resistance and shear displacement when the bolt is pretensioned.

Grouting as a method of strengthening and sealing rock, soil and concrete is widely used. The possibilities of sealing structures are of great importance from both an economical and environmental point of view. The cost of grouting has in certain projects been as high as the cost for the blasting and excavation of the tunnel. To improve the technique of grouting with cement based material, it is necessary to focus on the properties of the used grout mixture. The ability of a grout to penetrate cavities, channels and porous material, the penetrability, depends on two things, the theology and the filtration tendency. Extensive laboratory tests on stable, low w/c-ratio, injection grouts show that the most significant limitation to their penetrability is the tendency of cement grains to agglomerate into an impermeable filter cake. The properties of a grout that may prevent passing obstructions in the flow path without the cement grains clogging and preventing further penetration is in this work called filtration tendency. An inert material mixture and a cement-based mixture are used for the investigations in this work. The inert material, which is crushed dolomite stone, does not react with the added water in the mixture. The used cement grouts are based upon three types of commercial available Portland cements and four Portland cements with modified grain size distribution curves. Performed tests show that the grain size and grain size distribution is of great importance for the filtration tendency. According to performed experiments with inert and cement material, it seems to be advantageous for the penetrability to have a grain size distribution that contains neither too many fine or coarse grains. It is reasonable to believe that the grain size distribution should be relatively steep (narrow grain size range) between minimum and maximum grain size. The maximum grain size is of importance in terms of for example d95. Too large maximum grain size will prevent penetrat, QC 20101007

The use of full-depth precast concrete bridge deck panels is becoming more and more attractive to transportation authorities throughout the country. In comparison to conventional cast-in-place decks, precast decks are of higher quality, allow for the bridge to be opened to traffic in less time and are easier to maintain, rehabilitate, and replace. This ultimately results in lower costs for transportation authorities and less disruption for the motoring public. Unfortunately, the use of precast deck panel systems is hindered by the lack of design standardization and information regarding the performance of such systems. This research focuses on a key element of the system, the mortar or grout, which is used to connect the precast panels to the bridge girders by filling the space in the horizontal shear pockets and the haunches. Several essential mortar characteristics were identified and investigated in order to create a specification that indicates required performance criteria for mortars. This specification can be used to determine whether particular mortars or grouts are suitable for use in a full-depth precast concrete bridge deck panel system.

Confined, unconfined, dynamic, and quasistatic compressive tests were conducted on strain gage instrumented specimens of concrete, mortar, and granite to produce data for determination of the parameters of an elastic/viscopiastic (EVP) constitutive model of these materials. In addition, concrete grout specimens were tested in dynamic and quasistatic compression to observe columnar fracture and changes in ultrasonic wave speeds. The EVP model captures the basic features of the material behavior such as strain-hardening, confining pressure, rate influence, creep, and relaxation phenomena. The model is applicable to fully 3-D stress conditions, but all parameters can be determined from the results of a few quasistatic and dynamic tests. Reasonable agreements between model and tests were obtained within the natural scatter of the data., Prepared in cooperation with University of Florida, Dept. of Aerospace Engineering, Mechanics and Engineering Science, Gainesville, Florida.

The full-width, full-depth precast panel system is very convenient for rehabilitation of deteriorated decks as well as for new bridge construction. The horizontal shear strength at the interface between the two interconnected elements is of primary importance in order to provide composite action. The strength of the bond between the two precast members should be high enough to prevent any progressive slip from taking place. Flexural strength, shear strength and deflection characteristics all depend on the satisfactory performance of the interface to provide composite action. However, the case when both of the interconnected elements are precast members bonded by means of grout, is not currently addressed by ACI or AASHTO. This is the main impetus for this project. A total of 36 push-off tests were performed to develop a method for quantifying horizontal shear strength and to recommend the best practice for the system. Test parameters included different haunch heights, different grout types, different amount and different type of shear connectors. Two equations, for uncracked and cracked concrete interfaces, are proposed to be used in horizontal shear design when the precast panels are used. Predictive equations are compared with available methods for the horizontal shear strength of the precast panel system. Conclusions and recommendations for the optimum system are made.

The mechanical and physical properties of various geologic materials and man-made grouts have been determined. The testing was in support of the Defense Nuclear Agency's (DNA) Treaty Verification program. Specifically, test data was generated for use with DNA's HYDROPLUS program. The tests performed included unconfined compression tests, uniaxial strain tests, physical properties, ultrasonic velocities, XRD mineralogy, and lithologic descriptions. In some instances, gas gun samples were prepared and shipped to DNA's gas gun experimentalists.

The research study described in this report focuses on determining the engineering properties of the resin modified pavement (RMP) material relating to pavement performance and then developing a rational mechanistic design procedure to replace the current empirical design procedure. A detailed description of RMP is provided, including a review of the available literature on this relatively new pavement technology. Field evaluations of four existing and two new RMP project sites were made to assess critical failure modes and to obtain pavement samples for subsequent laboratory testing. Various engineering properties of laboratory-produced and field-recovered samples of RMP were measured and analyzed. The engineering properties evaluated included those relating to the material's stiffness, strength, thermal properties, and traffic-related properties. Comparisons of these data to typical values for asphalt concrete and Portland cement concrete were made to relate the physical nature of RMP to more common pavement surfacing materials. A mechanistic design procedure was developed to determine appropriate thickness profiles of RMP, using stiffness and fatigue properties determined by this study. The design procedure is based on the U.S. Army Corps of Engineers layered elastic method for airfield flexible pavements. The WESPAVE computer program was used to demonstrate the new design procedure for a hypothetical airfield apron design.