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Guler, Erol/0000-0002-3492-387X; WOS:000445635700006 In this study, pullout performance tests were conducted on five prestressed ground anchors having different tendon bond and unbonded lengths. The tendon bond lengths of the tested anchors varied from 4 to 10m, whereas the unbonded lengths were in the range of 8-16m. The tests were performed separately on a dense, gravelly sandy soil slope with an inclination of 90 degrees in Cottbus, Germany. The anchors were inclined downwards at an angle of 15 degrees below the horizontal. The results indicated that three of the five anchors did not satisfy the acceptance criteria as outlined in DIN 4125 Standards. According to the acceptance criteria, the line that was composed of the elastic displacements of the unbonded length had to remain between two specific limit lines. Although the elastic displacements of the unbonded tendons were taken into account for the acceptance of the anchors, the length of the unbonded tendon did not have a significant effect on stability. The anchors having unbonded lengths of 8, 13, and 15m failed, whereas the anchors with unbonded length of 9 and 16m were accepted after the termination of the performance tests. However, the tendon bond length was proved to be an important parameter that contributed to the acceptance of the tested anchors. Test results indicated that anchors having tendon bond lengths longer or shorter than 6m were rejected.

This paper, consisting of full-scale pullout tests and theoretical analyses, focuses on the behavior of ground anchors under ultimate load conditions. Three ground anchors with a bonded length of 4 m were built in slightly weathered limestone and tested until their ultimate load capacities were passed. The test data indicated that two of the anchors performed well with the ultimate load capacities being nearly 3 times of the design values. The remaining anchor performed below expectation, which was diagnosed of poor grouting. Furthermore, an analytical framework was developed considering the elastoplastic stress-strain relationship at the anchor-rock interface. The developed model revealed that the bond stress was not uniform along the entire bonded length when the ultimate state was reached; instead, the bonded length was composed of plastic and elastic zones. The length of elastic zone was not significantly influenced by the increased load, while the plastic zone extended with the increase of the load. The average ultimate bond stress over the entire bonded length was a function of anchor diameters and bonded length. Thus, current recommended presumptive ultimate bond stresses should be used with caution if the anchor is very short ( 12 m).

In this paper, the stabilisation of a 60 m-high natural slope located in Fujian Province in southeast China is analysed using finite-element and limit equilibrium methods. The strength reduction finite-element analysis was able to capture the behaviour of the slope before stabilisation and its performance after stabilisation. The factors of safety obtained with the two different approaches are compared and discussed in this paper. Deformation analysis was also conducted to investigate the serviceability of the slope during the stabilisation construction activities. The results show that the combination of slope flattening and ground anchors was able to provide the required stabilisation while satisfying serviceability requirements, as the deformations at the crest and toe of the slope were within tolerable limits.

An anchored sheet wall is commonly used in retaining deep excavations. Anchor force is one of the critical design parameters in practice. Based on the kinematical admissible failure mechanism, a limit analysis approach to determine the anchor force is presented. The explicit formula for the anchor force is given, which makes it easy to calculate using a simple calculation program such as MS Office Excel. Anchor force is mainly influenced by seven parameters: the internal friction angle; cohesion of the soil; wall friction angle; surcharge on the ground surface; dip angle of the anchor; penetration depth of the wall; and depth from the anchor force action point on the wall to the ground surface. The relevant quantitative calculation can be performed by the proposed method. In addition, the design anchor force under a specified design safety factor and the anchor forces of multiple rows of anchors are also illustrated in this paper. To verify that the method is reasonable, the predicted and measured anchor forces are compared in two classical soil-nailed wall experiments. The result shows that the presented method is applicable.

This paper deals with numerical and experimental investigations of specific problems of guided wave propagation in ground anchors, focussing on recognizing the phenomenon of the energy transfer between anchor components. Particular attention is paid to characteristic features of guided waves propagating in free and embedded parts of the tendon, at the interface between the tendon and the surrounding anchor body, as well as waves diffracted on the start of the anchor body. Anchors with variable lengths and diameters of the anchor body, as well as anchors with non-reflecting boundary conditions, are analysed numerically. Experimental measurements are conducted on laboratory models of ground anchors of different fixed lengths. The study shows that the detailed recognition of the phenomenon of the transfer of the wave energy between the tendon and the anchor body is crucial for the appropriate application of the guided wave propagation method for non-destructive inspection of ground anchors. The obtained results indicate that the three most important geometric parameters, i.e. the anchor body length, the free length of the tendon and the thickness of the anchor body, can be determined on the basis of wave propagation signals recorded at the free end of the anchor.

Ground anchors have been playing an important role in reinforcing dykes, underground, stabilizing structures of earth retaining walls, subway stations, and anchoring abutments of bridge or in sea port, etc. In Vietnam, the design of ground anchors is generally based on the international design guidelines, in particular the Eurocode. As there is a diversity of current design practices in different countries, it is necessary to carefully verify and validate an international design of ground anchor before adopting it to Vietnam. This paper aims at presenting a series of full-scale pullout tests of ground anchors recently performed in several projects in Hanoi and Ha Long city, Vietnam. The testing results in terms of the ultimate load-holding capacity, the pullout performance and the skin friction are discussed and compared with the French design practice TA95 in order to evaluate as well as to improve its applicability in Vietnam.

Fully grouted ground anchors have been increasingly used as a part of foundation system to resist buoyant force in geotechnical practice. However, designs of fully grouted anchors are commonly based on the calculation of the ultimate pullout capacity along with safety factors, which results in unnecessary economic loss. This is partly due to the fact that it is impractical to predict the anchor performance without strong assumptions of how steel tendons, soils, rock, and grout can collectively resist pullout force or without detailed information of the ground parameters. As one of the promising fields within the framework of artificial intelligence, Machine Learning (ML) has been increasingly used to address geotechnical problems by giving computers the ability to learn without being explicitly programmed. Multivariate Adaptive Regression Splines (MARS) is an ML nonparametric algorithm that is based on a data-driven process. This paper presents the development of a MARS performance prediction model using data from 530 anti-floating anchor pullout tests in 8 different projects in weathered soils and rocks located in Shenzhen, China. In this study, MARS demonstrates the capabilities to capture the complex non-linear relationships in the anti-floating anchor pullout problem. In addition, it is shown that the displacement-based design procedure of the anti-floating anchor based on the MARS model is feasible if appropriate safety factors are adopted.

Drag anchor is an economical foundation option for offshore floating structures. Although there are studies on ultimate pullout capacity of drag anchors, the drag-in installation process is still not fully understood. The approach using yield envelopes for drag anchor under combined loading for the installation behavior prediction is promising. However, more needs to be done to understand anchor bearing behavior during the installation process. The current study focuses on the capacity of drag anchor under uni-directional vertical, horizontal and moment loading in uniform clay and the behavior of anchor fluke under combined loading. Finite element analyses are conducted for “wished-in-place” anchor fluke. The effect of anchor embedment depth and soil overburden pressure is investigated. The horizontal and rotational capacity factors for different embedment ratios and overburden pressure ratios, which have not been covered in the existing studies on anchor capacity, are provided here. The effect of anchor/soil interface breakaway condition on the capacity under the three uni-directional loading is also studied. Based on the understanding of drag anchor capacity under uni-directional loading, its behavior under combined loading is characterized by the yield envelopes for both shallow and deep anchor behavior. The current study provides a good understanding for the capacity of drag anchors. The yield envelopes can be used for the prediction of anchor trajectory with consideration of both shallow and deep anchor behavior.

The practice of design shows that the need to develop explanations, recommendations and examples of calculations to go with the essential requirements of the building rules. The author has set the task to simplify the use of the requirements for the design and construction of soil bases for cylinder open caissons. The objective of the work is to develop the fixing design of an underground structure of 24 m in diameter and 15.6 m in height, immersed in an antifriction jacket below the groundwater level to depth of 16,8 m, to prevent it from floating up. The article describes the geological structure and soil characteristics of St. Petersburg, a characteristic feature of which is the presence of groundwater horizons in the soils, complicating underground constraction. Recommendations and explanations are given as to how to forecast the forces of friction at the point of contact between the structure and the water-saturated soils. The constractive scheme of securing embedded structure from floating up has been developed. The methods of calculation and design of additional loads and ground anchors is described in detail. The results of calculation and analysis have been performed to verify the probability of the open caisson floating up due the action of the hydrostatic load. The main types of construction work are cementation of the antifriction cavity, building on the perimeter of the well of a reinforced collar rigidly connected with the front shaft, providing a sandy backfill as additional load for the well, anchoring the bottom of the well using vertical ground anchors. The paper may be of interest to designers working in the area of the design of underground structures.

Construction cranes are subject to a variety of external factors that affect stability and safety. Modern solutions do not provide sufficient stability and safety. To eliminate the threat from various factors, new support elements have been proposed. To assess the effect of soil anchors on the stability of a crane, a theoretical experiment was conducted, with various assumptions. The coefficient of cargo stability with ground anchors is determined and compared with the load stability factor with standard outriggers.

To solve the anti-float problems of underground buildings (structures) more economically, environmentally and effectively. The paper putted forward a construction technology of revolving conical pullout anchors based on researching and improving to the traditional pullout measures. That was a method that the conical anchor head was installed on the drilling pipe and screwed into the stable soil under the influence of drilling pipe. When pulling the drilling pipe, the fine aggregate concrete were poured into the edge. Furthermore, prestressed anchor cable should be strained which connected with the anchor head to keep a good connect with the beam so that it could improve pullout capacity. The conundrums of long construction period and high cost had effectively solved. This technique also had provided great reference values for the congener construction.

Torpedo anchors are used for station keeping of floating offshore platforms and fixing risers to the seabed in deep water. Their main benefit over other anchors is reduction in anchor installation cost via free falling in the water. A torpedo anchor has a steel cylindrical shaft with a conical tip and is ballasted in order to deepen the soil penetration and increase the anchor holding capacity. In order to address the installation effects on the soil strength and consequently the anchor pull-out capacity, first reconsolidation (set-up) of soil next to the anchor after installation is studied by a finite-element (FE) analysis of coupled deformation and fluid flow in porous media. The results of the set-up analysis indicate the rate of dissipation of excess pore-water pressure and soil-strength recovery. These are important considerations in predicting the anchor pull-out capacity at different times after installation. In the absence of a documented complete set of installation and set-up tests, the results are validated qualitatively using available albeit limited field test data.

Rapidly erectable, folding structures comprised of sandwich panels offer light-weight, energy efficient sheltering solutions. Field implementation requires better understanding of the impact of the erection conditions and fabrication errors on behavior, including (1) out-of-level ground conditions, (2) number/location of ground anchors, and (3) fabrication-related warping of panels. This paper investigates the behavior of a folding sandwich panel (fiber-reinforced polymer faces and foam core) structure using an experimentally validated finite element model to perform parametric studies that focus on variable out-of-level ground conditions, anchorages, and panel warping. Ultimately, this paper addresses research gaps required for field implementation and provides design recommendations.

The performance of retaining walls in Dublin Boulder Clay under undrained conditions is relatively well understood. These structures show very modest lateral movements; this is attributed to the inherent strength and stiffness of the boulder clay and the very slow dissipation of excavation-induced pore water suctions. There are few data available on the long-term behaviour of such walls, however, both in Dublin and elsewhere. The economic downturn in Ireland provided a unique opportunity to improve understanding of the long-term behaviour of these types of excavations. Several temporary works retaining walls remained in place for long periods due to work on the projects having been suspended. The paper gives details of several such projects but focuses on the performance of the 14 m high secant piled wall with a single row of ground anchors at Heuston South Quarter. It was designed as temporary works but remained in place for about 7 years, with movements increasing to over 50% more than those predicted at design stage. The paper will present a detailed account of the Heuston wall design, construction and performance and the subsequent remedial works, which were carried out to ensure its long-term stability.

In this study, we analyzed the methods and technologies used for constructing earthworks and military engineering in the latter period before the industrial revolution in Poland. The research object, the Warsaw Citadel, is a source of knowledge about military heritage from the aspect of conservation and protection of specific engineering achievements, which were dictated by early Russian geopolitical doctrine. Within the framework of the ongoing project of material heritage protection and popularization of history, the fortress has been transformed into a modern museum building. The new symbolic message of architecture was redefined, leaving behind the gloomy dominance elements in the scenery of the nearby city. In this study, reception tests of ground anchors were used for analysis. They were treated as a tool to determine the heterogeneity of fortification of historical earthworks. In the presented calculation procedure, limitations in the availability of geotechnical tests were overcome. Geological terrain layout and embankment excavation technology significantly impacted their quality and reliability. Currently, the embankments are slashed with anchored retaining walls. Ground anchors were used at short distances and were tested according to the national standard procedures. The results of the load tests are based on the physical properties of the subsoil, the conditions of contact with the supporting elements of the anchors, and the material properties. The soil interaction with the anchors is described using a rheological model, the constants of which were obtained using a fractional derivative model. The spatial variability of the rheological model parameters is presented using theoretical semivariograms matching the empirical data. The semivariograms explain the spatial correlation of the tested constants of the rheological model of the substrate with the anchors. The results of non-destructive testing were influenced by factors such as time and consolidation processes. The obtained results allowed us to directly draw conclusions about the repetitiveness of embankment features and indirectly about the quality of their construction.

To apply the compression-type anchor to deep roadways, this paper analyzes and summaries the bearing mechanism, shear stress distribution of the grout body and engineering application of the compression-type anchor. The analysis shows that the compression-type anchor has the advantages of reasonable grout body stress form, high loading capacity, good corrosion resistance and durability. The analysis also indicates that further study on the stress distribution of the compression-type anchor’s grout body and the design of a new compression-type anchor with high strength initial support, simple structure, and small diameter that is suitable for the surrounding rock in deep roadway engineering is necessary to apply compression-type anchor supporting technology to the deep roadway.

In the article are presented modern and economical solutions for reducing time of passing by and for improving attractiveness of the old part of the city. Transit road is designed on an underground level (lower part) with distribution ways (ramps-on and ramps-off) to the ground level (upper part). Tram traffic stayed on the ground level with track beds over tunnels or directly on cantilevers structures. In the article are presented results of complex engineering calculations and choice of economical, structural and functional final arrangement.

With the application of innovative anchor concepts and advanced technologies in deepwater moorings, anchor behaviors in the seabed are becoming more complicated and pose a great challenge to the analytical methods. In the present work, a large deformation finite element (FE) analysis employing the coupled Eulerian–Lagrangian technique is performed to simulate the installation/mooring line, and then is applied to analyzing comprehensive anchor behaviors in the seabed. By connecting cylindrical units with each other using connector elements, the installation/mooring line is constructed. With the constructed installation/mooring line, FE simulations are carried out to investigate comprehensive anchor behaviors in the seabed, including long-distance penetration of drag anchors, keying of suction embedded plate anchors and non-catastrophic behavior of gravity-installed anchors. Through comparative studies, the accuracy of the proposed method is well examined. A parametric study is also undertaken to quantify the effects of the frictional coefficient, initial embedment depth, and soil weight on the profile of the embedded anchor line and the shackle load. The present work demonstrates that the proposed FE model, which incorporates the installation/mooring line and the anchor, is effective in analyzing the comprehensive anchor behaviors in the seabed.

The paper describes the design, construction and testing of some 3600 temporary single-bore multiple anchors used to support the deep basement that formed part of the foundation support system for the Kuntsevo Plaza, a pedestrian-oriented, mixed-use development in the Kuntsevo district of south-western Moscow, Russia. Single-bore multiple-anchor technology was used effectively to provide support for a 45 m deep diaphragm wall constructed to support a 25 m deep excavation in the geotechnically challenging Moscow mixed soils, comprising combinations of low-strength clays, sands and silts. Previous attempts to sustain the required workloads of up 600 kN in the anchors had failed due to unacceptable creep. However, an understanding of the concept of progressive debonding, and the use of this knowledge in the design of efficient fixed anchor lengths, proved highly effective. Also, the introduction of fixed anchor enhancement techniques such as end-of-casing grouting in granular soils and post-grouting in cohesive soils enabled anchor capacities more than double those previously achieved in the prevailing ground conditions. Also described is the extensive programme of investigation tests conducted to establish important parameters regarding the behaviour of the ground and the performance data relating to the ground anchors that effectively limited wall displacements; this was a crucial requirement due to the sensitivity of adjacent underground services.

Soil-retaining structures, such as anchored, gravity and diaphragm walls can be used effectively to stabilise unstable, shallow slopes. The present work focuses on assessing the passive soil pressure that can be mobilised by passive and active retaining structures used for slope stabilisation purposes; passive structures are taken to be those left free to move and find their own equilibrium against the soil pressure, and active structures those equipped with pre-stressed ground anchors that lead to an upward movement against the unstable sloping soil. The numerical analyses performed with the Abaqus finite-element code and the comparison drawn with available theoretical solutions show that, in the case of passive retaining structures, the maximum horizontal soil pressure that can be exerted by the unstable soil layer on the retaining structure is independent of soil–wall friction and coincides with Rankine's passive value. However, in the case of active retaining structures, the passive soil pressure may be much greater than Rankine's value and should be evaluated as suggested by Eurocode 7 (geotechnical design). Such a high soil pressure is only meaningful for the purpose of sizing the retaining structure, however, because (just uphill from the stress region perturbed by the soil–wall friction and ground anchor) the stress state at rupture coincides with Rankine's theory in the case of active retaining structures too. Thus, even in the case of anchored retaining structures, the maximum soil pressure that can be exploited for slope stabilisation coincides with Rankine's value. These conclusions have important consequences for the dimensioning of soil-retaining structures for slope stabilisation purposes. A practical application for slope stabilisation is discussed in the final part of the paper.

The effect described by the Euler formula for a flexible line being under tension and wrapping around a rigid support is experimentally proved to implement in the case of a nonrigid support being a ground base. Model and field experiments show essential rise in the load-bearing capacity of ground anchors with flexible tendon—E-anchors, owing to this effect. Equipment for installation of the anchors is designed and trialed. Using DEM, a 2D problem on the efficiency of the new anchors as a function of direction of pull out force applied to the tendon is solved. The E-anchors are supposed to be promising for the application in construction and operation of engineering structures.

Although the concept of sheet pile bridge abutments is not new, they do not enjoy as much widespread usage as reinforced concrete bridge abutments. This paper provides a design case-history involving replacement of two existing road bridges with proposed new bridges supported by a combination of steel sheet piles and concrete bearing piles as abutments. The steel sheet piles have been designed to provide lateral earth support while concrete piles, vertical deck loads. Sheet piles of different types: anchored, tied-back and cantilever, have also been proposed for wingwalls. The arrangement for abutments was selected to minimize traffic interruption over existing road bridge, to enable faster construction in a restricted space environment and reduce ‘possession’ of railway track, and to provide an economic and durable solution. The two road bridges are a part of preparatory works for electrification program of Denmark state railway network between Aarhus and Lindholm.

Ground anchors and anchored systems have been successfully used as cost-effective soil supporting systems for highway safety considerations for decades. However, some unique challenges exist when these systems are used in Alaska and other cold regions. One challenge associated with anchor installation could be potential thawing of the warm permafrost as a result of grout mortar hydration; this thawing might undermine the capacity of the anchor. Therefore, this study aimed to develop an innovative antifreeze grout mortar for successful application of anchors in cold regions. A testing matrix of different combinations of chemical admixtures was developed, and workability, early-age strength, and freezing point of the mix water of mixes were evaluated to determine the optimum mix designs. Test results showed that the antifreeze grout mortar achieved three primary objectives: ( a) it depressed the freezing point of the mix water available for the hydration process, ( b) it accelerated the early-age strength gain at low temperature, and ( c) it enhanced excellent flowability for grouting. The laboratory results were further validated through fieldwork in a test section located inside the Cold Region Research and Engineering Laboratory permafrost tunnel.

Pull-out experiments were performed on four carbon fiber-reinforced polymer (CFRP) ground anchors simulating their applications in rock and soil. The CFRP tendons used in these anchors comprise a single-strap end on both ground and air sides. On the ground side, the single-strap end is embedded in a prefabricated cylinder of high-strength grout that fits into the borehole. In rock applications, the ground-side anchor can be used without additional confinement, while in the case of soil, an additional CFRP confinement ring is needed to prevent premature grout failure in the strap region. The load transfer from the strap to the grout cylinder occurs progressively; approximately 50% of the load is transferred at the semicircular strap end, while the remaining 50% is transferred at the curved transition from the strap to the rod segment of the free length. (C) 2016 American Society of Civil Engineers.

Aiming at the current situation of anchor bolt and cable arrangement in mine roadway support, the paper analysis the mechanical characteristics and mechanism of bolts and cables, and numerical simulation method is used to comparison and analysis of pre-tension distribution characteristics under different anchor bolt-cable arrangement. The research indicated that separate anchor bolt-cable layout in different sections, anchor bolt and cable force stable equilibrium, coordinate with each other, at this time roadway surrounding rock of shallow and deep pretension distribution more reasonable, can play a role of bolt anchor cable synergistic action, and form the best pre-tension load-bearing structure, which is helpful to keep the stability of coal roadway.

In the past decade, different types of underreamed ground anchors have been developed for substructures requiring uplift resistance. This article introduces a new type of umbrella-shaped anchor. The uplift behavior of this ground anchor in clay is studied through a series of laboratory and field uplift tests. The test results show that the umbrella-shaped anchor has higher uplift capacity than conventional anchors. The failure mode of the umbrella-shaped anchor in a large embedment depth can be characterized by an arc failure surface and the dimension of the plastic zone depends on the anchor diameter. The anchor diameter and embedment depth have significant influence on the uplift behavior. A finite element model is established to simulate the pullout of the ground anchor. A parametric study using this model is conducted to study the effects of the elastic modulus, cohesion, and friction angle of soils on the load-displacement relationship of the ground anchor. It is found that the larger the elastic modulus and the shear strength parameters, the higher the uplift capacity of the ground anchor. It is suggested that in engineering design, the soil with stiffer modulus and higher shear strength should be selected as the bearing stratum of this type of anchor.

In the process of thickened oil thermal recovery, the pre-stress cementing needs to be anchored at the bottom of the casing pipe. And the reliable opening and closing of anchor flukes directly influence the anchoring. In allusion to the problems of how to get the critical value of drilling fluid flow rate of when the anchor flukes begin to open, completely open, begin to close and completely close, whether different nozzles can open or close reliably, getting the corresponding differential pressure and discharge coefficient of the different nozzles, this paper conducts a study from both theory and experiment to obtain the relevant parameters. By simulating the anchor in actual work and dealing with the data, we conclude that: (1) The fluke can open smoothly when the flow rate reaches a certain flow and it can also close smoothly when the flow rate declines. (2) The critical flow rate of the flukes, when two kinds of anchors are with different nozzles, has been acquired. (3) Corresponding differential pressure and discharge coefficient of the different nozzles in different flow rate have been ascertained.

Anchoring technique has been widely used in slope engineering because of its reinforcing function to rock and soil mass. Yet the full understanding of the anchoring mechanism still lags behind the engineering practice. This paper introduces the design process and construction technology of the grouting anchor in slope reinforcement engineering. Based on bolt grouting test, it is found that the effective anchorage length of the grouting anchor depends on the size of the anchor solid and relative physical and mechanical properties of surrounding rock and soil. Research shows that the distribution of shear stress is uneven along the anchoring length. It mainly amasses within the front 1/3 part of the anchoring and increases with the development of outside load. The conclusion is helpful to describe the anchoring mechanism and instructive for engineering practice.

In this paper, the feasibility of using evolutionary computing for solving some complex problems in geotechnical engineering is investigated. The paper presents a relatively new technique, i.e. evolutionary polynomial regression (EPR), for modelling three practical applications in geotechnical engineering including the settlement of shallow foundations on cohesionless soils, pullout capacity of small ground anchors and ultimate bearing capacity of pile foundations. The prediction results from the proposed EPR models are compared with those obtained from artificial neural network (ANN) models previously developed by the author, as well as some of the most commonly available methods. The results indicate that the proposed EPR models agree well with (or better than) the ANN models and significantly outperform the other existing methods. The advantage of EPR technique over ANNs is that EPR generates transparent and well-structured models in the form of simple and easy-to-use hand calculation formulae that can...

The main phase of excavation for the basements of the British Library at St Pancras, London, was completed in 1987. The project included basements extending up to 25 m deep, through the London Clay and into the Lambeth Group. The excavations were formed using both the top-down method and open excavation with ground anchors. Existing major buildings lie within 25 m of the site and London Underground tunnels lie below and adjacent to the site. The purpose of this paper is to present the results of displacement monitoring; they are summarised in the paper and presented in more detail in online supplementary data files. The retaining walls advanced towards the site by up to about 32 mm and the clays expanded rapidly on unloading beneath the excavations, causing the Victoria Line tunnels to heave by up to 22 mm. The slow progress of the project provided an unusual opportunity to monitor ground and structure movements in the surroundings before site activity began. Ironically, it was found that the largest settlements of adjacent buildings were caused by the installation of equipment intended to measure the settlements. Extensive condition surveys were carried out, but no damage to adjacent structures or tunnels has been recorded.

This paper aims to reveal the mechanical effects of metal holder and bolt (anchor) in anchor frame combination structure, then shows existing problems of anchor frame combination supporting structure being used in present coal mine, and gives corresponding solution on the basis of modern mechanics theory. By specify examples and on the basis of having administered the pull test of bolt (anchor), the article has calculated and analyzed the stress distribution rule of metal holder in anchor frame combination supporting structure according to the statically indeterminate principle in solid mechanics. In contrast to single metal holder structure, the consequence comes to be that the bearing capacity was significantly increased. However, the actual stress values of bolt (anchor) in field measurement shows that the bearing capacity of bolt (anchor) has hot been given full work. So the essay not only reveals the good bearing capacity of anchor frame combination structure but also points out that there is plenty of scope for optimization in anchor frame combination structure, and its research results have a certain reference for supporting theory and technology research in deep level and high ground pressure soft rock roadway.

This paper presents an innovative soil anchor in loose and dense sand. Many studies on the anchor plates, both theoretical and experimental, have been conducted, although the existing works were mainly performed on regular and symmetrical anchor plates. A new anchor system is an irregular and non-symmetry shape anchor. This is an innovative system due to the special shape and the penetration into soils. Two sizes of irregular-shaped anchors, 159 and 297 mm, were used. The non-symmetry anchor employed in the system contributes to its good performance and high pullout load capacity. The maximum resistance increased based on the embedment ratio and the density of the sand. An important innovation of this system is the installation method, where it does not require excavation and grouting. The main objective of this research is to validate the break-out factors and the ultimate uplift capacity load of the irregular-shaped anchor with the existing researches related to anchor plates. The experimental research was performed on the models in a chamber box. For the 159 mm-width irregular-shaped anchor, an embedment ratio L/D between 1 and 7 and for the 297 mm-width embedment ratio L/D between 1 and 4 were employed. The irregular-shaped anchors were used in dry, loose and dense sand. The new irregular-shaped anchors are compatible with the symmetrical anchor plates as determined by existing researchers.

This paper analyses the problem of locking value of anchor cable of pile anchor supporting of a deep foundation pit in the north of Kunming city. There are many influencing factors of locking value of anchor cable such as relaxation loss of anchor cable materials, tensioning system, pre-stress loss caused by anchorage friction, geological conditions and so on. And the author put forward the corresponding treatment measures for achieving the stability of supporting structure.

In this study, an analysis about the causes of different types of excavation on accidents is required in order to prevent the frequently occurring accidents related to the earth retaining structure and excavation. Also, analysis of influence was performed by using numerical typical soil conditions and construction trend using numerical analysis method. According to the analysis results of 25 accident cases, the main influence factors were found as following: insufficient of soil survey, instability of temporary facility and lack of groundwater treatment, etc. Furthermore, in the numerical analysis result of 22 cases, drainage method was occurred larger settlement than waterproof method in the Inland. In case of applying the earth anchor method, it needs more detailed in the regions, which are discovered soft ground or rock discontinuities. Also, The consolidated clay absolutely needs further consideration of excess hydrostatic pressure.

The application of FLAC2D software long ditch coal mine extraction tunnel without support boltgrouting. Anchor when the anchor rope supporting and strengthening supporting state ofroadwaywere simulated and analyzed the change of roadway surrounding rock under differentsupport forms. Demonstrated the possibility that the current anchor cable anchor supporting andanalysis under the condition of the coal wall broken grouting bolt is the necessity of reinforcement.

The main factor, anchor damage, leading to the faults of submarine optical fiber cables (SOFC) were analyzed, and the significance of the research was illuminated on the anchor holding process. Also, the force situation of the anchor holding process was analyzed quantitatively under some assumptions; subsoil vibration characteristics caused by the anchor were analyst with mathematical modeling.

Since the pre-stressed anchor technology became to be used from the beginning of twentieth century, it is widely used with the advantages of its good applicability, high cost performance, good looking appearance and easy green. Pre-stressed anchor achieves the purpose of actively controlling foundation pit deformation by exerting pre-stress on steel strand of its free section. This thesis chooses deep foundation pit engineering, adopt Mohr-Coulomb ideal soil body by finite difference software FLAC3D, and select different anchor pre-tension values to simulate. It combines Lizheng software to do numerical simulation and analytic study on pile-anchor supporting structure. This thesis compares results coming from the two kinds of software, and analyze the impact on row piles' body bending moment, pile top deformation, anchor cable axial force and foundation pit deformation when pre-tension changes.

supporting structure parameters optimization is always a research focus in soft rock tunnel. Combined with Youfangping tunnel in Guzhu highway, the scheme of long anchor supporting has been provided. Usually the length of systematic anchor was determined according to experience, it often not reasonable. In order to determine the length of anchor, in-situ wave velocity test and theoretical calculation was used, and with the consideration of safety and economy, the length of anchor was determined as 4.5m finally; At the same time combined with in-situ monitoring measurement, two test sections was selected, and with the comparison of the designed supporting scheme and the original strong supporting scheme, it can be found that: no matter from the sight of surrounding rock deformation, stress applied on surrounding rock or force pattern of supporting structure, the supporting form by lengthening anchor can control surrounding rock deformation more effectively, can improve the bearing capacity of surrounding rock fully and improve the effect of supporting structure. And the supporting scheme of long anchor was more reasonable than the strong supporting scheme. This long anchor supporting scheme can provided new thought to supporting design of soft rock tunnel in Guzhu highway.

Anchors are primarily designed and constructed to resist outwardly directed loads imposed on the foundation of a structure. These outwardly directed loads are transmitted to the soil at a greater depth by the anchors. Buried anchors have been used for thousands of years to stabilize structures. Various types of earth anchors are now used for the uplift resistance of transmission towers, utility poles, submerged pipelines, and tunnels. Anchors are also used for the tieback resistance of earth-retaining structures, waterfront structures, at bends in pressure pipelines, and when it is necessary to control thermal stress. In this research, we analyzed the uplift behavior of plate anchors in clay using a laboratory experiment to estimate the uplift behavior of plate anchors under various conditions. To achieve the research purpose, the uplift resistance and displacement characteristics of plate anchors caused by the embedment ratio, plate diameter, and loading rate were studied, compared, and analyzed for various cases.

During prestressed cementing for heavy oil thermal recovery wells, it is encountered that the earth anchor connecting to the bottom of the casing string anchors difficultly, and anchoring force can not meet design requirement. A new type of unit and resettable earth anchor structure for prestressed cementing is introduced. The project can use multiple unit combination according to different formation condition and can choose different length of the earth anchor fluke according to diameter of the well. ANSYS/LS-DYNA is used to simulate the process of the fluke digging into the wall of the borehole with different diameter. Variation of reaction force of rock upon the fluke with different initial digging angle is analyzed, and the most favorable angle range in which the fluke digs into the borehole wall is concluded. A favorable reference to determining fluke's geometric parameter and selecting type of the claw is provided.

Floating offshore structures have been actively studied mainly for the application of oil productions in the past. Presently, this asset from oil industry finds its way for the application to floating wind turbine systems. Tensile forces in mooring systems pull the anchoring systems at the connection, and due to the combination of anchor weight, wind, wave, and current, the anchor may experience inclined forces. The main scope of this paper is to analyze the ultimate holding capacity of suction caisson anchors according to the anchor dimensions and anchor translation angle based on finite element analysis. The holding capacity is linearly proportional to the embedment depth of anchor when installed in uniform soil. The shape of failure envelope becomes more angular as the anchor gets slenderer. The depth of optimal loading point is found to be at 0.57 times the length.

The bearing capacity of a self-opening ground anchor is calculated using the empirical method and the plaxis software package. Stresses and strains can be determined in each element of the anchor using the approach based on the use of modern software packages enables to evaluate the stress-strain behavior of soil-structure system (geotechnical conditions taken into account), as well as the behavior of soil-anchor system as a whole and its individual elements. It is possible to estimate stresses in the area affected by the ground anchor, as well as the stability of the soil-anchor system as a whole.

A deep foundation pit is located in Zhengzhou city, is located in the Yellow River alluvial plain, excavation depth of 12.9 m, engineering site surrounding environment is complex, the soil for silt and silty clay layer, embedded depth of groundwater in the shallow. In the foundation pit supporting design, combining with the field information and physical and mechanical parameters of soil, the elastic foundation beam method considering interaction between supporting pile, anchor and soil and the deformation coordination, selection of CU cohesive force, internal friction Angle parameters of the experiment. "M" method is used to reflect the interaction of piles and soil, anchor cable using common pull type high pressure jet grouting anchor cable, anchor cable and the high pressure jet grouting anchor cable selection, increase the anchor stiffness, inhibit deformation. Through anchor stress, deep horizontal displacement of foundation pit monitoring process monitoring data, it is concluded that the rationality of the design of foundation and construction feasibility. Through engineering practice, under the premise that ensure the security of foundation pit side wall, has obtained the good economic benefits. Through the system summary and analysis for the pile anchor supporting system similar to the soil and surrounding environment in Zhengzhou region to provide experience for the design and application of reference.