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The railway industry has focused on the improvement of maintenance through the use of novel technologies. Recently, the utilisation of repair welding to restore the worn area on wheels has been investigated, as it can bring significant savings in wheelset maintenance. Under an Innovate UK AURORA project, a worn wheel that previously operated on London Underground (LUL) was restored using this process. To test its performance and compare with a new standard steel grade wheel, the HAROLD full scale test rig was used in which an LUL vehicle bogie equipped with both the restored and R9 grade wheels was operated under the representative lateral and yaw displacements computed from vehicle dynamics simulations. The wear measurements carried out at the end of test cycles showed that although the restored wheel suffered from initial higher wear, the levels reduced and became similar to the R9 grade wheel. Furthermore, the full-scale testing provided an opportunity to validate the wear model predictions which were conducted using the vehicle dynamics simulations utilised in testing inputs. It was found that while the flange wear predictions were higher, the tread wear estimations were smaller than the measurements on the R9 grade wheel.

The need to consider tunnel safety, especially with respect to fire, has been highlighted in the past by various severe tunnel fires that have occurred throughout Europe. This article provides a ge...

Slender load-bearing masonry walls are typically used in low-rise commercial and industrial settings, where they are an efficient system to resist out-of-plane forces and gravity loads. Mas...

This paper reports results of full scale testing to further explore potential GCL damage mechanisms in earth dam retrofit applications in seismically active areas; in particular, to a) investigate whether shear displacements could reduce the magnitude of GCL panel overlap during earthquake shaking; b) explore the influence of gravel particles on GCL thickness at localised point of contact; and c) observe the consequences of an accidental exposure of an uncovered GCL to short duration rainfall in terms of moisture content and effects during subsequent compaction. The results of these experiments indicate that even under severe shaking no movements were detected at the GCL panel overlap. Whereas gravel particles were observed to locally reduce the thickness of the GCL to 2.2 mm, no plowing of the particle into the GCL occurred due to a lack of shear displacement at the interface, resulting in no localised internal erosion through the barrier. Furthermore, hydration of GCL panels during construction due to surface wetting was observed to result in a state of hydration less than its post-construction state. These results indicate that although each of the three GCL damage mechanisms cannot be ruled out to ever be relevant in practice, the performance of the GCL retrofitted earth dam tested was satisfactory under even severe Level 2 earthquake shaking, and suggests that the retrofitting of small earth dams with GCLs is a promising strategy to improve their static and seismic resistance.

The paper focuses on the approach to assessing the number of launches of anti-aircraft missile products at various stages of full-scale tests required for the implementation of development work. We analyzed the approach to determining the extent of flight tests using the practical experience of the “MKB” Fakel” of 1960s. Furthermore, we proposed a method for estimating the cost of the experimental stage of development work

The FAA National Airport Pavement Test Facility (NAPTF) is a full-scale accelerated pavement testing facility located in Atlantic City International Airport, New Jersey. Six flexible and three rigi...

The initial full-scale experiment in Costa Rica began in 2012 under a program that has been identified as PaveLab. The main purposes were to identify the effect of typical construction prac...

In a period characterized by the urgent need of enhancing the safety level of the building stock, including architectural heritage, externally bonded textile reinforced mortar (TRM) systems are emerging as a particularly advantageous strengthening solution. Their use on unreinforced masonry arched members appears one of the most promising fields of application, but an improved understanding still needs to be gained on the behaviour of TRM retrofitted interstorey vaults. This paper describes an experimental investigation on full-scale masonry vaults, provided with buttresses and backfill, reinforced with basalt textile reinforced mortar (BTRM) overlays either at the intrados or at the extrados. Cyclic load was applied at 1/3 span over the backfill. Digital Image Correlation was used to detect full-field displacement measurements and map crack development. Both strengthening solutions proved effective in delaying crack occurrence and improving arch-fill interaction, enhancing both the load-carrying and the deflection capacity. A limit analysis based method provided reliable ultimate strength estimates for engineering design and assessment purposes.

Owing to the lack of a comprehensive published procedure for the design of stiffened extended shear tabs, practicing engineers usually follow design guides for unstiffened shear tabs. The results of recent laboratory experiments and numerical analyses have demonstrated that improvements to this approach are warranted. Furthermore, design methods for this connection type under combined axial and shear forces are not well established. To address these shortcomings, full-scale laboratory tests were carried out on the double-sided configuration of stiffened extended beam-to-girder shear tab connections with full depth shear plates. These experiments were complemented by a continuum finite element (CFE) study, with which the axial force demands along with other critical parameters that affect the connection behaviour were further examined. The experiments supported by the CFE findings indicated that the primary connection damage states are mainly associated with yielding and fracture of the shear plate due to the interaction of flexural, shear, and axial force. The study demonstrated that the direction and magnitude of the applied axial force significantly affected the shear and axial demands along the centerline of the interior bolt line. The current design practice for the double-sided configuration of the full-depth extended beam-to-girder shear tab was also evaluated; a significant underestimation was observed in the prediction of a connection’s ultimate resistance.

The IsaMill™ was specifically developed to address the energy efficiency issues associated with grinding to fine and ultrafine sizes. It has been doing this successfully for nearly 25 years in more than 125 installations. Recent efforts by Glencore Technology to further improve the energy efficiency of the IsaMill™ have resulted in the development of a new IsaMill™ shaft spacer design. The spacer was developed through laboratory, pilot and full scale testing prior to being commercialised. Full-scale results indicate that the new configuration was able to reduce the specific energy consumption by 13–17% in an M1000 gold application grinding to a P80 of 18 µm. The spacers were also shown to have no adverse impact on the shape of the product particle size distribution. This paper discusses the development process of the new spacers through lab, pilot and full scale trials, operating results and processing implications.

A unique structural design was made for the glass facade of the Co-Creation Center building in Delft. The roof is completely carried by the glass fins. The fins are laterally stabilized by being included in the triple glazed facade. To certify the safety of the design full scale tests on the fins were done at Delft University of Technology. Due to a transportation accident the fins were damaged at one end. This allowed an additional study into the effect of this pre-test damage on the residual compressive stressed induced by the tempering. It was found that the residual stresses were not significantly affected by the damage. During the compression tests no cracks developed at the damaged ends. A load of 200 kN, more than double the maximum design load did not produce failure in the prototypes. After intentionally seriously damaging all plies of the fins, the fins could still carry the 200 kN load for 30 min without buckling or other failures being noted. Measurement of the residual stress in the outer plies of the fins after damage showed that sufficient residual stress was present in the larger fragments of the prototype to provide enough stability in combination with the Sentryglass laminating foil.

We present the results of an extensive large-scale experimental campaign on the dynamic response of rubber–gravel mixtures as an innovative seismic isolation material. In the first series of experiments, the foundation soil immediately below the prototype structure of EUROPROTEAS was replaced only with gravel to serve as benchmark tests, while in the following tests two rubber–gravel mixtures with increasing rubber content per mixture weight were used. The experimental campaign included free- and forced-vibration tests. A large number of instruments of various types (accelerometers, seismometers, shape-acceleration arrays, and laser sensors) were installed on the structure, in the foundation soil and at the adjacent soil surface in order to obtain a well-instrumented 3D set of recordings to study the response of the structure and wave propagation in soil media. In this study, we seek to investigate the isolation capability of the rubber–gravel mixtures under dynamic loading. Our primary goal is to assess the effect of the rubber content of the improved foundation soil in the stiffness and the damping of the soil-structure system.

Frequently, deep foundations extend through liquefiable sand layers and bear on more competent layers at depth. When liquefaction occurs, the skin friction in the liquefied layer would be expected to decrease to near zero; however, as pore pressure dissipates and the liquefied layer settles, negative skin friction can develop along the pile. This paper summarizes full-scale pile downdrag testing at four sites where liquefaction was induced by small explosive charges. Test were performed on driven piles, bored piles, augercast piles and micropiles. Despite the variation in pile type, observed performance was similar at all sites. Negative friction in the liquefied layers was between 40 and 55% of the positive friction before liquefaction as the sand reconsolidated. Negative friction in the non-liquefied layers was about the same as the original positive friction. Following liquefaction, the ground around the piles settled between 7.5 and 27 cm; however, pile settlement was typically small and was most dependent on the end-bearing resistance. Pile settlement and load in the pile were generally consistent with the neutral plane method. Steps necessary to estimate the neutral plane and pile settlement are summarized in the paper.

The innovative resilient slip friction joint (RSFJ) technology has recently been developed and introduced to the construction industry. This technology not only aims to provide life safety ...

This position paper was developed by members of the task force on “Energy Geostructures” of the International Society of Soil Mechanics and Geotechnical Engineering (ISSMGE) Technical Committee TC308 on ‘Energy Geotechnics’. The article includes a summary and review of some of the most recent analysis approaches, in situ testing, full scale testing and model scale experiments with a focus on energy piles and other energy geostructures. The geotechnics literature in these topics has increased rapidly in the last five years suggesting a surge in this emerging research area. Here complementary lines of research can be distinguished, one focusing on thermal analysis and another focusing on thermo-geomechanical analysis. Limitations, shortcomings and knowledge gaps are identified and needs for further research and development within the geotechnical community are highlighted.

The US design code provisions for steel special truss moment frames (STMFs) were formulated based on research work carried out in the 1990s with double-angle sections as truss members. To p...

The purpose of this project was to design and test a new bolt-down bollard system that meets the requirements of American Standards for Testing Materials (ASTM) Designation F2656-15 M50/P1 impact conditions. The test installation consisted of three vertical 10-in. diameter (nominal) bollards with welded base plates bolted to a shallow reinforced concrete foundation. The foundation for this system was sized to reduce the foundation embedment. Shallow foundations are often necessary for use in cities and urban areas where utilities can conflict with deeper foundations. Standard common members and materials were used in the installation to accommodate fabrication and installation in locations all over the world. The bollards can be removed to provide access if necessary. Full-scale testing was performed on the bolt-down bollard system. The bollard system design for this project successfully met the requirements of M50/P1 with a total payload penetration of less than 1 m. The new bollard design successfully met all the performance requirements for ASTM F2656-15 M50/P1. Details of the design and testing of the bolt-down bollard system are provided in this paper. Crash-testing videos and additional information on the design and full-scale testing will be provided in the presentation.

The paper addresses experiments to assess whether seismic systems can be used for autonomous border surveillance on land and sea. Seismic systems as an integral part of border surveillance systems, especially maritime ones, should comply with strict performance requirements. The first-priority problem was to prepare appropriate domestic equipment and an experimental technique for seismic surveying on land and sea. When this problem was formulated, there was no suitable domestic broadband equipment. Fundamentally new technical solutions were employed to create prototypes of seismic modules of the SM-5, SM-6, and SM-3M types. On their basis, one- and three-component short-period and broadband of seismic sensor prototypes were developed, including the SM-5M, SM-6, TS-5, TS-6MSh, etc., which were used to create a prototype for a digital deep seafloor seismic station (TsDSS-M). Also, for transition zones, a seafloor seismic station was developed and tested, which is based on molecular electronic sensors that have achieved significant progress recently. The paper describes the prototypes of the TsDSS-M digital seafloor seismic station and MDM bottom seismic module for transition zones, both based on electrodynamic and molecular electronic sensors. The prototypes were tested on Lake Seliger. Shallow-water tests demonstrated the reliability and high performance of the prototypes; the desired characteristics proved to be appropriate. Importantly, TS-5 seismic modules are now manufactured at an industrial scale; this has solved the problem of import substitution in this area.

Conventional magazines for hazard division 1.1 are constructed using bricks and reinforced cement concrete (RCC) for which storage inside quantity distance (SIQD) is 2.4 W1/3 m, where W is Net Explosive Content in kg. New composite called laced reinforced concrete (LRC) has been developed recently, for which SIQD has been reduced up to 0.5 W1/3 m. Due to substantial reduction in separation distances, the requirement of land area has been reduced significantly. Although SIQD has been reduced drastically due to development of new composite, the other quantity distances like process inside quantity distance (PIQD) and outside quantity distance (OQD) decreased marginally. To reduce these quantity distances, the solution is multi-compartmented structures based on Unit Risk Principle. The application of unit risk principle enables the separation of explosives into compartments in such a manner that initiation of explosives in one compartment does not result in initiation of the explosives in adjacent compartments. This is achieved by special design of explosive storage buildings incorporating blast non-propagation walls between adjacent compartments storing explosives. Quantity distances are reduced for such magazines, as maximum credible limit corresponds to the quantity of explosive in one compartment. Present paper describes design and full scale testing of blast non-propagation wall between two compartments of a multi-compartmented explosive storage structure with storage capacity of 5 T Net Explosive Content (NEC) of HD 1.1 per compartment. The blast non-propagation wall comprising of sand filling and air gap between LRC walls has been designed for desired attenuation of blast parameters as well as for arresting high velocity fragments/debris. The design has been validated by fully instrumented design validation field trial. The conduct of the trial as well as the results are discussed in this paper.

This paper presents an experimental and numerical investigation of the use of external stiffeners to reinforce circular hollow section (CHS) X-joints under brace axial tension. Six full-scale specimens with different brace to chord diameter ratios (β) of 0.25, 0.50, and 0.73 are tested, including three unreinforced X-joints and three reinforced X-joints. The experimental setup and detailed parameters are presented and results including failure modes, load–displacement curves, and ultimate capacity are compared. The experiment results show that the reinforced external stiffeners clearly increase the mechanical performance of joints in tension, supported by the improved ultimate strength and initial stiffness in comparison to the unreinforced specimens. Furthermore, the enhancement of ultimate strength increases along with the increase of brace to chord diameter ratio (β). Finite element (FE) modeling using SHELL181 element is also established and precisely describes the static behavior of the X-joints under brace tension with and without external stiffeners.

This study aimed to investigate the effect of multi-wheel loading gear configuration on loading-induced failure potential of airfield flexible pavements. Field response testing was conducted in the...

Clinical tests were carried out in the representative group of patients with focal left-sided pneumonia (5 men and 7 women aged 18–41). Special-use product was included in in-patient department patients’ diet: 2 tablets in the first intake, then 1 tablet 4 times a day. Course of treatment was 21 days. Biologically active dietary supplement was prescribed together with general therapeutic treatment according to generally accepted standards of care. Control group included 15 patients randomized depending on sex and age who took only medicine. The author measured body temperature, studied the results of general blood tests, determined the level of C-reactive protein and seromucoids, performed R-graphy of lungs, electrocardiogram before and after treatment, analyzed clinical symptoms (cough, type of expectoration, shortness of breath). Composition of the special-use product was scientifically justified taking pharmacological characteristics of its ingredients and their active agents into account. Introduction of the biologically active dietary supplement in addition to the prescribed therapeutic treatment gave positive effect in relation to the inflammatory process: the patients could easier clear their throats from expectoration, coughed less frequently, and had less intense shortness of breath. It was evident that symptoms of disease recrudescence decreased. It appeared in the decreased intensity and length of fever. In case of acute respiratory viral infection the biologically active dietary supplement had antipyretic activity due to the anti-exudative effect of its ingredients. The author determined the anti-inflammatory effect and reduction of acute intoxication symptoms taking the results of general blood analysis into account. Patients who took special-use product had lower values of an inflammatory process marker – seromucoids. Tissues restored easily. The tested product has anti-inflammatory, antipyretic and analgesic properties. It can be used in complex treatment of acute inflammatory diseases and recrudescence of chronic inflammatory processes.