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Geotechnical engineering projects involving retaining walls require the calculation of lateral earth pressures behind these walls. This paper assesses several analytical solutions available in the literature for the calculation of at-rest, active, and passive lateral earth pressures behind rigid retaining walls. The calculated lateral earth pressures from these analytical solutions are compared with the measured values from small-scale tests, full-scale tests, and/or numerical simulations available in the literature. Small-scale tests showed similar normalized at-rest, active and passive lateral earth pressures as compared with full-scale tests/numerical simulations. The comparisons show that the calculated lateral thrust using the method by Jaky (J Soc Hung Archit Eng 78:355–358, 1944) and Janssen (Verein Deutscher Ingenieure, 39: 1045-1049, 1895) with a low wall-soil interface friction angle well matched the measured at-rest lateral thrust in the field tests and those by Coulomb (Essai sur une application des règles de maximis et minimis a quelques problèmes de statique, relatifs a l’architecture, Academie Royale Des Sciences, Paris, 1776) and Zhou et al. (Rock Soil Mech 35:245–250, 2014) agreed better with the measured passive lateral thrusts in the small-scale tests and full-scale numerical simulations than those by other methods. The calculated lateral thrusts using the methods by Coulomb (Essai sur une application des règles de maximis et minimis a quelques problèmes de statique, relatifs a l’architecture, Academie Royale Des Sciences, Paris, 1776), and Handy (J Geotech Eng 111:302–318, 1985) and Paik and Salgado (Geotechnique 53:643–653, 2003) with appropriate wall-soil interface friction angles matched the active thrusts in both small-scale and full-scale tests reasonably well.

To explore the load-bearing performance and the failure patterns of the lining structures, a full-scale loading test on the three-ring staggered assembled shield tunnel segments is carried out through a hydraulic loading system. In the experimental study, the segments’ internal force, convergence deformation, and displacement, and the bolts’ internal force, are analyzed. According to the experimental results, the relationship between internal force and deformation is obtained to determine the residual bearing capacity of the shield tunnel at each stage. Three stages are specified for the evolution of the segment’s maximum bending moment during the loading process, in which, the elastic stage is the main and longest stage, in which the bending moment of the segment increases the most. There are two stages for convergence deformation development and segment misalignment development. At the end of loading, the segment’s maximum positive and negative convergence values reach 61.22 and −57.69 mm, respectively. Besides, the maximum segment misalignment is 3.67 mm, which occurs in the direction of 90°. The segment cracks when its maximum convergence value reaches 25.03 mm. Moreover, there are signs of fracturing on the waist joint of the segment when its maximum convergence value reaches 32.73 mm. The concrete at the waist joint starts fracturing in pieces when the segment’s maximum convergence value reaches 38.93 mm, which is defined as the type of shear failure. Finally, the bearing capacity of shield tunnels during segment failure period can be evaluated by using the corresponding relationship between deformation and internal force.

Strong excitation effect on the outer windshield structure induced by unsteady airflow around the connection between carriages has been normally detected in full-scale tests, which leads to violent vibration of the outer windshields due to strong nonlinear fluid–structure interaction (FSI) between the flow field and the structure. Previous studies normally treat the outer windshield structure as rigid bodies, and the coupling effect between unsteady flow and elastic structure has not been considered. The purpose of this study is to establish a two-way iterative FSI model based on a full-scale test, obtain the flow field characteristics around the outer windshields through FSI simulation, and analyze their vibration mechanism and characteristics. The results show that the iterative computing of two-way coupling has good applicability for the analysis of the vibration of the outer windshields of a high-speed train (HST). The relative deviation of the surface pressure of the outer windshield between the test and simulation is 4.3%, and the relative deviation of the main frequency of pressure change is 1.9%. Under the action of aerodynamic loading, two opposite U-section rubber capsules produce dislocation deformation movement, which produces bending deformation, and the deformation vibration frequency is close to the first-order natural frequency of the structure. Then, under the coupling action of aerodynamic, elastic, and inertial forces, the vibration mode close to the high-order natural frequency of the outer windshield structure is excited, and the displacement phase of the outer windshield presents prominent periodicity. This study can provide a reference for the study of aeroelastic problems of the external structure of HSTs.

Air curtain is an effective means to stop the propagation of smoke in buildings to provide smoke-free area for safe egress of occupants in case of fires. To understand its effectiveness of smoke confinement in tunnel fires, full-scale tests were conducted in a tunnel of 140 m long and with varying heights of 5.0 m to 5.9 m and varying widths of 5.8 m to 10.8 m. A 20 cm-wide air curtain spanning entire lateral section was installed underneath the tunnel ceiling. The experiment showed that air curtain at exit velocities of 12 m/s and 16 m/s can stop the propagation of smoke produced by 1 MW fire and 2 MW fire respectively. Numerical simulation using ANSYS FLUENT was then conducted and the numerical results were basically consistent with those of experiment. To explore how the design parameters of air curtain, i.e., the width, the exit velocity and its angle, affect its effectiveness of smoke confinement at varying heat release rates, a number of numerical simulations were further conducted. The relationship of design parameters of air curtain with heat release rates was proposed and it can be used in the design of air curtain in tunnel fires.

Construction of precast reinforced concrete (PRC) industrial halls in seismically active areas has been increasing in recent decades. As connections are one of the most sensitive and vulnerable zones of PRC structures, there is a need to pay special attention to their investigation and modeling in seismic analysis. Knowing that each PRC system is specific and unique, this study aims to evaluate the actual seismic performances of PRC industrial halls built in the AMONT system, which represent a significant portion of the existing industrial building stock in Italy, the Balkans, and Turkey. As there is a lack of published research data on its specific joints, the results of the quasi-static full-scale experiments carried out up to failure on the models of four characteristic connections are presented. Since the implementation of nonlinear dynamic analysis in everyday engineering practice can be demanding, a simplified model of the structure considering the effects of the connections’ stiffness is proposed in this paper. The differences in the roof top displacements between the proposed model and the model with the rigid joints of the analyzed frames are in the range from 16.53% to 66.93%. The values of inter-story drift ratios are larger by 10–100% when the real stiffness of connections is considered, which is above the limit value provided by standard EN 1998-1. These results confirm the necessity of considering the nonlinear behavior and stiffness of connections in precast frame structures when determining displacements, which is particularly important for the verification of the serviceability limit state of structures in seismic regions.

Pultruded Fiber Reinforced Polymer (FRP) profiles are increasingly used as structural elements in civil infrastructure. However, the anisotropic elasticity and the application‐driven slenderness make them prone to local buckling failure at loads well below their ultimate capacity. This study adopts a combined experimental and numerical methodology as a design tool to characterize the behavior of hollow pultruded FRP profiles under three-point bending. Experimental tests were first carried out on small-scale (coupon) specimens to determine the most relevant material properties, followed by full-scale loading of simply-supported beams under three-point bending loads. Subsequently, a non-linear finite element analysis (FEA) of the full-scale tests was carried out in ABAQUS to gain more insight into the sequence of damage evolution. In this regard, Hashin’s failure criterion was used to model the failure of composite material. The results show that the structural integrity of hollow pultruded FRP beams is often governed by the local buckling rather than the material strength. In addition, Hashin’s damage criteria proved to be an accurate tool for investigating the failure modes of the hollow pultruded FRP beams.

A comprehensive laboratory testing program, field-testing program, numerical analysis, and life-cycle cost analysis were conducted to evaluate the beneficial effects of incorporating shrinkage-reducing admixture (SRA), polymeric microfibers (PMFs), and optimized aggregate gradation (OAG) into internally cured concrete (ICC) mixtures for rigid pavement applications. Results from the laboratory program indicate that all the ICC mixtures outperformed the standard concrete (SC) mixture. All the ICC mixtures showed a decrease in drying shrinkage compared to the SC mixture. Based on the laboratory program, three ICC mixtures and one SC mixture were selected for the full-scale test and subjected to a heavy vehicle simulator for accelerated fatigue testing. Extensive testing and analysis have shown that ICC mixtures incorporating SRA, PMFs, and OAG can be beneficially used in pavement applications to achieve increased pavement life. Keywords: critical stress analysis; full-scale test slabs; internally cured concrete (ICC); optimized aggregate gradation (OAG); polymeric microfibers (PMFs); shrinkage-reducing admixture (SRA).

To reduce the maintenance requirements during the service life of highway bridges and enhance the cracking resistance of concrete slabs in the hogging moment zone of continuous composite girders, this paper proposes an innovative girder-to-pier joint for composite bridges with integral piers. Compared to the existing ones, this new joint has structural differences. The middle part of the embedded web is hollowed out to facilitate the construction, and the upper and bottom flanges of the steel girder within this joint are widened. Moreover, cast-in-place ultra-high-performance concrete (UHPC) is applied instead of normal concrete (NC) only on the top surface of the pier. A full-scale test was carried out for this new joint to evaluate the load–displacement relationship, load–strain relationship, crack initiation, and crack propagation. Compared with the numerical simulation results of the reference engineering, the test results demonstrated that the proposed joint exhibited excellent flexural performance and cracking resistance. This paper also proposes a calculation method for the elastic flexural capacity of the girder-to-pier joint incorporating the tensile strength of UHPC, and the calculated result was in good agreement with the experimental result.

To tackle the problem of various types of rail damage, such as rolling contact fatigue (RCF) or wear, a profound knowledge of the occurring mechanisms is necessary. This paper presents a newly developed full-scale test rig experiment that involves inserting softer pins into the rail head. These tests help deepen our understanding of shear deformation in rail steels. Furthermore, a finite element (FE) simulation approach is introduced that can be related to the test rig experiments. With these experiments, in combination with the FE simulation, valuable information regarding the plastic deformation can be obtained. This methodology allows predictions regarding a rail’s material behaviour during cyclic wheel loading. Moreover, it enables an effective and rapid qualitative material assessment, reducing the costs of expensive and time-consuming experiments.

This paper presents the methodology of LCF equivalent tests based on the application of test samples whose stress-strain state (SSS) is similar to the stress-strain state of the part in its critical zone by using the stiffness coefficient of the stress-strain state. Requirements for manufacture of test specimens have been defined. This method was successfully tested on the example of a gas turbine engine LPC disk. The method was also used to improve the design of disk / blade root connection which resulted in a 3-fold increase of low cycle fatigue life of the disk. Method of equivalent testing is intended for prediction of cyclic fatigue life of critical large-sized parts full-scale tests of which are not possible or economically feasible.