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Many bridge abutments suffered failures due to large lateral deformations due to seismic shaking. During earthquakes, bridge abutments restrict the bridge deck's intrusion towards the backfill soil by generating passive earth pressure, which provides resistance to lateral deformation. As a result, the backfill takes the earthquake induced inertial forces transmitted from the bridge superstructure through abutment. Now a days, GRS bridge abutments are widely used due to their many advantages. In this paper, the behaviour of these GRS bridge abutments under large displacements such as 1 m lateral push into the soil due to the impact of bridge deck has been analysed and studied. It is observed that the GRS abutments with longer geogrids are observed to show better passive resistance.

After reviewing the complex and varied geology of France, the soil investigation commonly performed for pile projects is described. The types of piles and the execution methods used in the country are also given. The design rules for axially loaded piles, recommended by the French code for foundations ‘Fascicule 62-V (1993), based on Menard pressuremeter test (PMT) and on cone penetration test (CPT) results are presented in detail (including formulae and charts). The relevant factors of safety are given, both for ultimate and for serviceability states. The t-z method for obtaining the axial load-axial displacement behaviour of a pile, from PMT results, is described. Finally, the national practice for integrity testing and for load testing of piles is given.

A widely adopted technique for retrofitting of RC beam at soffit is through adhesively sticking external plate of FRP/Steel. However, an increase in applied load leads the plated beam to fail prematurely in debonding and peeling that largely develop from tension region; thereby, compromising the composite action between the plate and the beam that was initially designed to fail in a desired capacity. In recent decades, a significant research has been focussed to understand the influence of premature modes of failure on the capacity of plated beam; however, not much success is achieved in predicted premature failure, which is largely pertaining to complex nature of the materials involved. As premature modes of failure are highly uncertain, the author suggests that any such investigations are not complete without a proper characterisation (qualitative and quantitative) of different modes of failure in terms of their relativ e behaviour and dependency on different parameters. To understand and address these issues, author has proposed a quantitative parameter brittleness of failure that can be used to relate different modes of failure and measure their dependencies on beam parameters. The objective is achieved through a non-linear numerical tool model generated using ABAQUS, with the combination of discrete and continuum models, whose accuracy is validated through literature in terms of modes of failure (behaviour: location, initiation and propagation), load/displacement behaviour and capacity. At interface this was possible by adopting Cohesive Zone Model innovatively such that the same model could be used to define adhesive parameters as well as crack properties; thereby, through this merging technique it is now possible to control interfacial debonding

Stiffened steel columns are widely used in bridge piers due to their structural and constructional efficiency. The bridge pier is one of the main structural components in elevated highway transportation. The ability of structures to survive severe earthquakes depends on both strength and ductility. In this study, the stiffeners with different cross-sectional configurations are introduced to improve the strength, ductility and energy absorption capacity of thin-walled steel box columns. All cross-sections are designed with the same cross-sectional area and height for different stiffener arrangements. The columns are analysed by finite element method, incorporating both material and geometric nonlinearities under constant axial load and lateral cyclic loading. Using the lateral loadlateral displacement behaviour, the cross-section with two middle stiffeners shows high strength and ductility capacity. But examining energy absorption behaviour, the cross-section with corner stiffener shows high capacity among analysed columns. Therefore, by considering strength, ductility and energy absorption capacity, the best cross-section is identified as the cross-section with two middle stiffener arrangement with a particular cross-sectional area compared with other cross-sections. In addition to that, local buckling patterns of the columns are examined at different displacement levels to understand the failure modes.

The failure mode of anchorages placed close to the concrete edge and loaded in shear perpendicular towards the edge is often governed by the concrete edge breakout failure. The design provisions for concrete edge failure given in the current codes are limited in their application for anchor groups with rectangular anchor configurations only. The number of anchors in a row is limited to three for anchorages without, two for anchorages with hole clearance. Furthermore, for anchor groups with multiple anchor rows loaded in shear perpendicular and towards the edge, the failure load may be calculated by assuming the failure crack originating from the front anchor row (EN 1992-4) or from the back anchor row (fib Bulletin 58, ACI 318). The aim of this experimental study was to investigate the behaviour of shear loaded anchor groups of rectangular, triangular and hexagonal configurations undergoing concrete edge failure. A comprehensive experimental program was carried out on single anchors and anchor groups of different configurations to obtain information on (i) the group behaviour, (ii) the crack initiation and propagation, (iii) the influence of the displacement behaviour of single anchors on the behaviour of anchor groups and (iv) the influence of hole clearance pattern. The testing concept, test setup and the detailed evaluation of the test results such as load-displacement curves of the groups, load-displacement curves of single anchors, measurements on the hole clearance pattern and the investigation of the crack pattern and failure mode are discussed in this paper. Based on the evaluation of the test results presented here, a new analytical model is being developed for the concrete edge failure mode of shear loaded anchor groups that will be presented in a future paper.

This work is dedicated to the study of the large-displacement behaviour of a spiral spring. Parameters that influence the local torsion stiffness of the beam that constitutes the spiral are varied and their effect is studied. Cross-sectional shape, orthotropic material orientation and prestress are the three classes of parameters that are varied. The effect that the local change in torsional stiffness has on the overall behaviour is illustrated in a linearised way by comparing in-plane and out-of-plane stiffnesses, and nonlinearly, by inspecting a graphical representation of the potential energy field of the system. Several embodiments composed of multiple spirals are showed to illustrate how the understanding of the nonlinear behaviour could be exploited in conceptual design of compliant mechanisms.

In this paper, the strength safety of a fuse cock main body has been analyzed by the finite element method. The stress and displacement behaviour characteristics have been investigated for thickness variations at the region of (T) between a ball valve and a fuse cock safety connector. The FEM analyzed results recommend that the optimized thickness at the region of (T) is from 1.55mm to 1.6mm for the supplied gas pressure of 1.5~3.5MPa. This is considered for the optimized strength safety and light weight of a fuse cock main body.

Steel bracing has proven to be a very powerful method to improve the seismic behaviour of reinforced concrete frame structures. In general the steel braces are indirectly connected to the RC frame via additional steel frames that are in turn fixed to the RC frame using post-installed anchors or reinforcing bars. However, this method comes with several shortcomings including increased weight and a disruption of the buildings function during installation. Therefore new connection approaches were developed where the braces are directly connected to the RC frame. One of the most promising solutions is the connection by means of post-installed anchors to connect the bracing to the frame corners. Using this type of connection allows an effective and low invasive strengthening of the structure. In this case the performance of the retrofitted structure is highly dominated by the performance of the post-installed anchors, since the imposed seismic demands are rather high. Therefore it is deemed necessary to assess the anchor performance under seismic actions, especially their displacement behaviour in the post-peak range. The current guidelines for seismic qualification of anchors only provide a force-controlled assessment procedure which is valid for non-structural connections but is not sufficient to obtain the information required for the assessment of their seismic performance in structural applications. A new displacement-controlled approach for the assessment of post-installed anchors under seismic conditions is presented. This approach allows the evaluation of the complete load-displacement behaviour as well as the hysteretic response of the anchors even in the post-peak range. A comparison with existing force-controlled assessment procedures shows that this approach is more suitable for the assessment of anchors used in structural strengthening applications under seismic actions.

Thin sheet materials of low bending stiffness but high membrane stiffness are often corrugated in order to achieve improvements of several orders of magnitude in bending stiffness with only minimal increases in weight and cost. If these corrugated sheets are initially curved along the corrugations, much of this stiffness gain is lost. In return, the sheets are then capable of significant elastic changes in shape overall, including large changes in overall Gaussian curvature. These shape changes are described here by non-linear and coupled kinematical relationships, which are verified against experiment and finite-element simulations. It is found that gross simplifications can be made about the large displacement behaviour of such shells without a loss of accuracy.

The present study concerns the analysis of the asymmetric displacement behaviour of the rear part of a motorcycle. Stylistic reasons led to the design of a vehicle with only one suspension located on the left-hand side. Experimental tests performed on a circuit with seven obstacles along a straight line confirmed that the bending displacement is higher on the right-hand side than on the left. This study aimed to perform a structural optimisation of the components involved at the rear end of the motorcycle, to find a solution to the problem. A hybrid approach is applied: the force acting on the suspension and bending displacements at the rear end were simultaneously measured in working conditions; a finite-element method model was then set up, validated and applied for design optimisation purposes. Both methodological aspects and applicative results are presented and discussed. Finally, a solution in accordance with design specifics is proposed.

In this paper a new analytical model is proposed to analyse the displacement behaviour of a tunnel face reinforced by bolts, using the homogenization approach for periodic media. Based on previous works, this new model was developed to take into account a finite bond strength of the grout–soil interface, which is more realistic than the perfect bonding assumption. The interface behaviour is simulated by an elastic – perfectly plastic constitutive law. The interface sliding occurs when the shear stress reaches the bond strength. This new feature allows for a more correct estimate of the bolt tension and the quantitative contribution of the bolt to reducing displacement of the ground surface. Despite using less restrictive hypotheses, the solution process remains sufficiently simple, thus preserving the analytical character of the solution. This new analytical model has been validated by three-dimensional (3D) numerical calculations using the finite difference code FLAC3D and by comparing its predictions with in situ data from the Tartaiguille Tunnel construction project, which forms part of the Mediterranean TGV (high speed railway) network. The developed approach results in simple and efficient design tools, which are very useful at the preliminary design stage of a project.Key words: tunnels, soil–structure interaction, reinforcement, numerical modelling and analysis, deformation, plasticity.

The present study concerns the analysis of the asymmetric displacement behaviour of the rear part of a motorcycle. Stylistic reasons led to the design of a vehicle with only one suspension located on the left side. Experimental tests performed on a circuit with seven obstacles along a straight line confirmed that the bending displacement is higher on the right side than on the left one. This study aims to perform a structural optimization of the components involved at the rear end of the motorcycle, in order to find a solution to the problem. A hybrid approach is applied: the force acting on the suspension and bending displacements at the rear end were simultaneously measured in working conditions; a FEM model was then set up, validated and applied for design optimization purposes. Both methodological aspects and applicative results are presented and discussed. Finally a solution in accordance with design specifics is proposed.

This paper examines the dynamic displacement-crushing force and dynamic displacement-absorbed energy behaviour of eight cars in full width barrier, 45% overlap rigid barrier and 30 degree angled barrier tests at 56, 50 and 56 kph respectively. The study shows that the frontal crush behaviour of these cars can be divided into three regions or zones of constant force.These zones are associated with crushing of the front structure as far as the engine, the engine and rear front structure and the occupant compartment. The highest average crushing force is associated with crushing of the engine and rear front structure with lower average crushing forces required for the extreme front of the car and for the occupant compartment. It is hypothesised that the energy absorbed-dynamic displacement behaviour in the full width barrier test represents the energy absorbed-mean displacement for all other crush configurations. This hypothesis is combined with the geometric crushing model for the car front to calculate the responses in the 45% overlap and the 30 degree angled barrier tests for one of the cars. A high degree of correlation is obtained. Further evaluation is needed to verify the hypothesis. (A) For the covering abstract of the conference see IRRD 899758.

A technique is developed for the analysis of multiple underream anchor systems resting in an elastic soil. This technique may be used to consider anchor systems involving arbitrary anchor inclination and depth beneath the soil surface, as well as arbitrary number, shape, size and spacing of underreams. The approach is largely analytical in nature and involves only a fraction of the computation required for a finite element analysis. Consideration is given to the effects of anchor depth and inclination to the soil surface, and the spacing and number of underreams upon the elastic response of anchor systems. On the basis of the results from this study, a simple, approximate mehtod for estimating the response of multiple underream anchors is proposed. This approach involves the use of several interaction charts, which are presented in the paper, and can be used as a hand method for estimating the load- displacement behaviour of quite general anchor systems to sufficient accuracy for most practical purposes. The use of the approximate approach is illustrated by an example (A). (TRRL)

The Rayleigh theory of inextensibility is used to predict the displacement behaviour of a thin-walled cylindrical shell subject to a static couple. The effect of the position of load application is investigated. Characteristic curves are presented for a series of load positions for constant shell dimensions, together with curves showing the effect of different shell sizes. Experimental verification of the theory is provided, tests being performed on a cylinder in which the loads are applied at the ends of a diameter. Satisfactory correlation was found between the experimental and theoretical results.

The investigation described in this paper examines the large displacement behaviour of thin-walled un-symmetrical section beams subjected to combined bending and torsion. The relevant theory is briefly described and a method of theoretical solution is given. The unstable nature of the behaviour is indicated and the requirements and design of a suitable experimental test rig used to verify the theoretical results are discussed. Typical experimental results are shown and compared with the corresponding theoretical values.

— This paper reviews the stress intensity factor, limit load, compliance and J-integral functions for a centre cracked tensile (CCT) specimen available in the literature. Compliance and J-integral functions are derived from the optimum stress intensity factor and limit load solutions. The functions are compared with the results obtained from two-dimensional finite element analyses of the specimen. The finite element results have confirmed the accuracy of the compliance and limit load functions available in the literature and suggest that the unloading compliance technique, based on crack mouth opening displacement, could be developed for a CCT specimen. Non-linear finite element analyses have shown that J can be estimated from the measured load versus load-point displacement behaviour providing a/W≥ 0.5

Curved alignments of highway bridges are often necessary for smooth traffic. Furthermore, architects are increasingly opting to more curves in building as aestheticism is being an important element in most designs. Unlike the case of un-curved structural elements, curvature induces complicated stresses and elements behaviour can be quite different from the behaviour of similar but straight elements. This research aims to develop an analytical procedure to predict the behaviour of curved thin-walled curved beams and develop a formulation that helps design against out-of-plane buckling. The analytical approach considers the nonlinear behaviour and large deformation. An extensive theoretical investigation on large displacement behaviour has been carried out using the principle of minimum total potential energy and compatibility equation. The paper presents the nonlinear equations that describe the elastic behaviour of curved thin walled panel. To verify the proposed equations, out of plane displacements are compared with the results of experimental testing. The proposed equations give a good agreement with the test results.