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In this study, a Finite Element (FE) model of locally strengthened high-strength stainless-steel tube subjected to lateral impact loads is established using LS-DYNA to investigate its dynamic behaviours. The accuracy of the FE results is verified by comparing with the test results. The impact force, bending moment, stress and strain responses as well as the internal energy dissipation histories of the strengthened tube are analysed during the entire impact process. The results indicate that the impact resistance of the strengthened tube is obviously enhanced as compared to hollow stainless-steel tube. Furthermore, parametric studies are conducted to reveal the influence of axial compressive force, impact position, impact velocity and material strength on the impact behaviour of the strengthened tube. The results show that the application of axial compressive force reduced the impact force and increased the deformations of the strengthened tube. The impact resistance of the strengthened tube performed an increasing trend when moving the impact position towards the support and increasing the material strength. In addition, the increase of impact velocity significantly reduced the impact duration. Finally, design recommendations and process were proposed to facilitate the application of locally strengthened tube. • The impact response of locally strengthened stainless-steel tube was numerically studied. • The impact force, bending moment, stress and strain response and energy dissipation were analysed. • Concrete was found to dissipate more impact energy than the other parts. • The effects of variant parameters on impact performances of the strengthened tubes were investigated. [ABSTRACT FROM AUTHOR]

• The dynamic response of thin-walled cylindrical shells subjected to lateral shock loading via foam projectile impact was systematically studied. • Structural deformation evolution, deformation/failure modes, and mid-point deflections of thin-walled cylindrical shells under lateral shock loading were experimentally measured. • The sensitivity of the dynamic response of thin-walled cylindrical shells to the impact momentum level and geometric parameters under lateral shock loading was numerically explored. • It is found that the deformation on the rear side exhibits two patterns: indentation and bulge, which are dictated by the combined effect of circumferential membrane forces and bending moments. A combined experimental and numerical study was carried out to explore the dynamic response of Q235 thin-walled cylindrical shells under lateral shock loading. The machined Q235 specimens were clamped on both sides and subjected to centered lateral simulated shock loading via foam projectile impact tests, with their dynamic deformation evolution, mid-point deflections, and final deformation modes experimentally measured. The mid-point deflections of the impact side are all positive (the direction of deformation is the same as the impact direction) while those of the rear side all exhibit negative values (the direction of deformation is opposite to the impact direction). To further explore this phenomenon, the method of finite element (FE) was employed to simulate the foam projectile impact, with good agreement against experimental measurements achieved. Using the validated numerical model, the effects of impact velocity, length-to-diameter ratio, and thickness-to-diameter ratio on the dynamic response of the thin-walled cylindrical shell were further analyzed. The direction of both side deflections and deformation modes are significantly affected by the impact level and the shell geometries. For the rear side, within the given range of impact momentum and geometric parameters, the numerically predicted deflection varies from −1.775 mm to 2.45 mm. Thereupon, the coupling of indentation and bulge deformation patterns are indicated, and their corresponding contribution changes are considered the main mechanism for determining the final deformation of the thin-walled cylindrical shell's rear side. [ABSTRACT FROM AUTHOR]

• Experimental research on the out-of-plane ultimate bearing capacity of high strength steel (HSS) arches with thin-walled I-section. • Examined the out-of-plane ultimate bearing capacity of 14 HSS arch specimens, considering variations in yield strength, cross-sectional dimensions, slenderness, rise-span ratios, and span. • The finite element analysis of HSS arch, accounting for residual stress and initial defects, demonstrated a high degree of alignment with experimental results. • Investigated the effects of yield strength, rise-span ratio, and slenderness on the ultimate bearing capacity of HSS arches. • Established axial force-bending moment (N-M) design formulas for the out-of-plane ultimate bearing capacity of HSS arches. This study presents an experimental investigation on the out-of-plane ultimate strength of high-strength-steel (HSS) I-section arches, which has not been reported previously. Fourteen I-section HSS arches having different yield strengths, cross-sectional dimensions, slendernesses, and rise to span ratios were tested under three-point symmetrical vertical loading. The corresponding out-of-plane deformation modes and strengths are identified. Subsequently, in order to predict the out-of-plane capacities of HSS arches, a finite element analyses is carried out, which takes into consideration residual stresses and initial geometrical imperfections. This analysis demonstrates a strong alignment with the experimental results, confirming the accuracy of finite element model and experimental results. Furthermore, the study comprehensively analyzes the influence of yield strength of steel, rise-span ratio, and slenderness on the ultimate bearing capacity of HSS arches. Through a parametric analysis, design formulas for the out-of-plane bearing capacity of HSS arches subjected to arbitrary compression forces combined with arbitrary bending moments are formulated. It is found that the out-of-plane ultimate strength of HSS arches is significantly influenced by the yield strength of the steel. Compared to a low strength steel (LSS) arch, the out-of-plane ultimate bearing capacity of the HSS arch increases with an increase in yield strength in the plastic stage, and the ultimate lateral displacement of the HSS arch decreases with an increase in yield steel strength due to the lower ductility of HSS. In addition, after reaching the out-of-plane ultimate bearing load of arch, the load-displacement curve of the HSS arch drops faster than the LSS arch. It is also found that the proposed design formulas can effectively predict the out-of-plane bearing capacity of HSS arches. [ABSTRACT FROM AUTHOR]

Built-up radially battened columns (RBCs), comprising several identical circular steel tubes interconnected by multiple radial-shaped battens, represent an innovative column design that combines aesthetic appeal with exceptional load-bearing capacity. This makes them well-suited for architectural applications in large public buildings such as stations and airports. The axial compressive strength design methods for the built-up RBC have been extensively explored in the authors' prior studies. However, in real-world engineering applications, built-up RBCs may experience simultaneous axial compression and varying directional bending moments, particularly when considering potential eccentric compression or wind and earthquake loads in public buildings. Currently, strength design methods for this loading condition are still lacking. To address this deficiency, this paper primarily delves into the failure mechanism and strength design methods for built-up RBCs experiencing combined axial compression and arbitrary directional bending moments. Initially, the sectional strength of the built-up RBC is investigated by using a shell finite element model (FEM) for the built-up RBC. It is revealed that the compression-bending sectional strength of the built-up RBC exhibits significant differences with varying bending directions and tube numbers. Moreover, in some bending directions, the M - N sectional strength curve of the built-up RBC exhibits convexity. By integrating theoretically derived equations grounded in the principles of materials mechanics with FEM numerical calculations, concise and practical design equations are proposed for accurately predicting the sectional strength of the built-up RBC under combined axial compression and arbitrary directional bending moments. Subsequently, The buckling strength of the built-up RBC is studied using the FEM, considering initial geometrical imperfections consistent with first-order flexural buckling and accounting for geometric nonlinearity. It is noted that the bending direction of the built-up RBC may deviate during loading. Besides, the M - N buckling strength curve of the built-up RBC is not as convex as its M - N sectional strength curve. Based on calculations from numerous examples, practical design equations for predicting the buckling strength for the built-up RBC under axial compression and any directional bending moments are introduced. The key findings of this paper contribute to the compression-bending strength design of RBCs, enriching RBC design theory and promoting the widespread application of built-up RBCs in actual engineering projects. [Display omitted] • The M - N strength of RBCs varies with different bending directions and tube numbers. • The M - N sectional strength curve of the built-up RBC is convex. • The built-up RBC's bending direction may deviate during loading. • The M - N buckling strength curve of RBCs is less convex compared to its M - N sectional strength. • The M - N strength of RBCs can be predicted by a quadratic function. [ABSTRACT FROM AUTHOR]

Focusing on aero-engine low-pressure rotor spline couplings, the nonlinear characteristics of bending stiffness and the mechanism were analyzed, a solid finite element model of spline coupling considering gear surface contacts was established, the static stiffness experiments of the spline couplings were carried out. Through simulation and experiments, the nonlinear variation law of the structural stiffness of spline couplings was studied, and then the influence laws of fit clearance, tightening moment and torque on bending stiffness were discussed. The research results show that, due to the different contact states and stress conditions of the positioning surfaces, the bending stiffness variations of the spline couplings were mainly divided into two stages, which had piecewise nonlinear characteristics. The bending stiffness of the spline couplings is sensitive to the fit clearances of the positioning surfaces, and reducing the fit clearances of the positioning surfaces may effectively improve the bending stiffness of the structures; tightening moment has little influence on the bending stiffness, and under low load conditions, torque has an obvious effect on the bending stiffness. [ABSTRACT FROM AUTHOR]

This paper presents the derivation and validation of a mechanics-based finite element for the analysis of shear-critical slender reinforced concrete beams and columns. The element can capture the load-deformation behavior associated with axial loads, bending moments, and shear in uncracked or cracked reinforced concrete using only a small number of degrees of freedom and easily measurable input parameters: the gross cross-section dimensions and steel and concrete material stress/strain curves. The element is specifically derived to represent the full reinforced concrete cross section (i.e., one element is required over the depth of a member) and consists of four nodes, with two translational degrees of freedom (DOFs) per node. This formulation facilitates modeling the interface regions between walls or joint regions, beams, or columns and lowers the numerical complexity and number of decisions that the user must make. The element shows improvements to results from design codes when validated against experimental results for 782 beams without shear reinforcement and 167 beams with shear reinforcement taken from the literature. By reducing the number of degrees of freedom, the element will allow relatively rapid two-dimensional (2D) nonlinear analyses of full reinforced concrete buildings. [ABSTRACT FROM AUTHOR]

High-filled cut-and-cover tunnels (HFCCTs) provide an ideal solution for reclaiming usable land in northwestern China due to the unique landforms of the Loess Plateau. To improve the safety and minimize the cost of such tunnels, most current methods focus on load reduction or a soil arching effect to reduce the earth pressure on cut-and-cover tunnels (CCTs). Although optimizing the design of HFCCTs is an important topic, very few studies have focused on modifying the cross-section of CCTs to improve their design. The modifications of cross-sectional design were proposed, and the vault optimization factor, F, was introduced. The optimal cross-sectional design of a CCT was determined using the finite element method. The experimental results verify that changes to the cross-section of a CCT’s lining structure can both reduce the required thickness of the CCT’s structure and increase the allowable backfill height above the CCT. The optimization is accomplished by modifying the cross-sectional design of a CCT to minimize the bending moment and allow the CCT to carry a more axially compressive load. [ABSTRACT FROM AUTHOR]

To further improve the transportation level of China's high-speed railway, it is urgent to research on the key technology of speed in for the existing 250 km/h high-speed railway. The track structure directly bears the train load, the adaptability of the track after the train speed increase is an important factor affecting the safe and stable operation of the train. Based on the field investigation, finite element analysis, numerical calculation and other methods, this paper studies the adaptability of ballasted track, ballastless track and designed track superelevation, and the technical conditions for the speed-increase track of 250 km/h high-speed railway are put forward. The main conclusions are as follows: the speed increase of ballasted track lines will cause the increase of dynamic indexes of the fastener and track bed, which will reduce the service performance of structures; the speed increase of ballastless tracks will cause the increase of the longitudinal and transverse bending moments of track slab and concrete base slab, and the longitudinal bending moment of track slab in subgrade section increases the most, which is 4. 7 kN · m/ m; considering the safety margin, the reinforcement of track slab and concrete base slab in the subgrade, bridge and tunnel sections meets the requirements of strength and crack width; after the speed increases, the track design curve superelevation should be adjusted to meet the requirements of minimum curve radius and transition curve length under different speed levels; after the speed increase, attention should be paid to the drainage of track slab structure, track smoothness, etc., and the relevant requirements of the current specifications should be satisfied. [ABSTRACT FROM AUTHOR]

The design of steel structures using elements with non‐uniform geometry is common in practice, both for aesthetic reasons and material optimization. Tapered beams are one of such examples which are widely used. This work is focused on the development of artificial neural networks to predict the critical moment of tapered beams subject to bending moments applied at the extremities since no analytical methods are currently available. Almost 70k data samples were calculated using the Finite Element Method (FEM) with shell elements and were used to train and validate the neural network models. The definition of the data samples was based on a random generation procedure with constrained geometric proportions to reduce their number. The accuracy of the developed model is further illustrated on some particular cases and against the FE results of other authors. Finally, it is demonstrated that neural network models are fast and reliable assessment tools that can be employed during the search of optimal structural solutions in the early design stages. [ABSTRACT FROM AUTHOR]

Transverse stiffeners are used in slender steel plate girders along the span to give web lateral support and increase plate girder shear resistance. According to several studies, transverse stiffeners are primarily engaged in out‐of‐plane bending to laterally limit the edges of the panel as it buckles, rather than axial compression to anchor the tension field. As a result, the axial loading defined in EN 1993‐1‐5 [1] for the design of transverse stiffeners, based on tension field action, is usually deemed to be substantially larger than that observed in laboratory testing and numerical simulations. The test results of six plate girders loaded to failure, with slender webs and two transverse stiffener geometries, are presented. FE‐models that accurately replicate the tests provide a thorough view of the plate girder behaviour. The stiffeners internal forces are evaluated during plate girder loading up to failure. The transverse stiffener internal forces attained by both models are compared. It is confirmed that both the axial compression and the bending moment in the intermediate transverse stiffeners are much lower than the values prescribed by the EN 1993‐1‐5 [1]. [ABSTRACT FROM AUTHOR]

Stainless steel became a relatively common material for load‐bearing structures in corrosive environment or when maintenance is difficult. The existing design rules cover all common cases. However, for some, the experimental or numerical data are very limited. This includes studies on welded I‐section beam‐columns. This paper presents a comprehensive experimental and numerical investigation into the structural performance of welded I‐section members loaded by compression and major axis bending moment. In total, eighteen test specimens were fabricated from grade EN 1.4301 austenitic stainless steel plates using two welding methods, namely conventional and laser welding. The experimental program on pin‐ended long beam‐columns is described in the paper. The loading eccentricities for the tests varied to provide a wide range of bending moment‐to‐axial load ratios. Nonlinear finite element models were developed in ABAQUS software and validated using the test results to simulate the beam‐column behaviour accurately. [ABSTRACT FROM AUTHOR]

The rising interest in the use of high strength steel (HSS) materials is justified by several advantages that they provide. In the field of construction, their benefits range from streamlined and elegant structures to lower CO2 emissions and energy consumption. High‐rise buildings and large span bridges can be designed with smaller foundations and less structural weight, since the application of HSS makes the design with slender steel sections possible. However, special attention should be given to the stability of the compressive members since the buckling resistance generally governs their design. The existing codes to evaluate the capacity of HSS columns and beam‐columns are based on rules from experimental tests related to normal strength steel (NSS) materials, which is responsible for inconsistencies. Therefore, this current work aims to present a numerical model created and validated to evaluate the major‐ and minor‐axis flexural buckling of HSS welded I‐section columns and the combined flexural and lateral‐torsional buckling of HSS welded I‐section beam‐columns. In the following, a parametric study is also conducted, in which different cross‐sections, normalized slenderness, steel grades (from S460 up), bending moment distributions and application of restraints are considered. Finally, a comparison between the European design rules and the resistances from the Finite Element model is led, evidencing the underrating expressed by the code with a level of safety even higher when superior steel grades are evaluated. [ABSTRACT FROM AUTHOR]

Copyright of Guangdong Architecture Civil Engineering is the property of Guangdong Architecture Civil Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study presents the experimental, numerical analysis, and dynamic impact analysis of a building collapse caused by a rainfall-induced landslide (vertical cut slope failure) on 15 August 2018, in Peringavu, Kerala, India, which resulted in the death of nine people. The volume of 1500 m3 soil-applied lateral thrust force on the building's rear side led to its demolition. The study includes extensive geotechnical characterization. General limit equilibrium and finite element methods were used in the numerical analysis. The infiltration analysis involved a rainfall pattern of low, moderate, and higher intensities on the slope. The study involved a two-stage analysis. Firstly, the analysis of the vertical cut slope with the application rainfall intensities, and second, the analysis of the building under the dynamic impact of the landslide. As a result of the study, the failure mechanism of the vertical cut during intense rainfall and triggering factors were evaluated. The dynamic impact analysis was carried out to examine the effects of the impact of the landslide debris on the building and the performance of the building under the impact load. The load-bearing walls experienced high-intensity impact force developed by the landslide, resulting in the lateral displacement of 170 mm and differential settlement of 92 mm, which led to the building's demolition. The flexural failures, excessive deflections, bending moments, foundation settlements, and displacement of structural elements were studied. [ABSTRACT FROM AUTHOR]

Prestressed, precast concrete piles using High-Strength Steel Strands (PPCPs using HSSS) are a new type of precast pile. Compared with prestressed high-strength concrete (PHC) piles, the adoption of ultra-high-strength concrete and HSSS not only improves the load-bearing capacity, but also enhances the ductility of precast piles. The engineering application of PPCPs using HSSS requires not only a high bearing capacity of the pile segments, but also reliable splicing to ensure cooperation between pile segments. Based on the characteristics of strand anchorage plates, this paper proposes a new combination splice using the clamp ring and welding (Combination Splice). The theoretical analysis and design method of this Combination Splice is introduced. This research gives a thorough investigation into the flexural performance of PPCPs using HSSS with the Combination Splice. The flexural tests of PPCPs using HSSS with the Combination Splice were firstly conducted on eight full-scale pile specimens with three different pile diameters and four different steel reinforcement ratios. The flexural performances are evaluated in terms of crack resistance, flexural capacities, crack distribution, as well as strain development. The results indicate that the Combination Splice remain safe and intact when the piles reach the ultimate bending capacity. The ultimate bending moment of tested specimens with the Combination Splice is, on average, 10% larger than that of specimens using a theoretical formula. In light of the experimental data, a finite element analysis (FEA) model has been created to simulate the flexural performance of the piles with the Combination Splice. The FEA results show that the load–displacement curves and crack distribution regions are in good agreement with the experimental findings, which verifies the reliability and accuracy of the FEA model. The parameter analysis investigates the effects of the assembly gap and clamp ring corrosion on the flexural performance of PPCPs using HSSS. The results show that assembly gaps have a greater influence on the flexural capacity and deformation, while the influence of the clamp ring corrosion is negligible, indicating that the Combination Splice has certain advantages in terms of durability. [ABSTRACT FROM AUTHOR]

Copyright of China Forest Products Industry is the property of China Forest Products Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper examines the effects of different loading patterns on the static characteristics of continuous concrete beams reinforced with external prestressed carbon fiber-reinforced polymer tendons (EPCFRPT) and qualitatively analyzes the results for two continuous concrete beams: SB-1 under symmetrical loading, and SB-2 under asymmetrical loading. Then, a finite element analysis model is introduced and calibrated by tests conducted at Southeast University and data collected from a literature review. Based on the FEA model, the initial prestress, cross-section area, and eccentricity of CFRP tendons as well as the steel reinforcement configuration were selected by a parametric study. The results indicated that the initial prestress and tendon cross-section area had the most influence on the tendon stress increment and the secondary bending moment of the middle support, while the reinforcement distribution and eccentricity of the tendons had little effect. The secondary bending moment had a linear positive correlation with the stress increment of tendons. These results allow a simplified equation for calculating the external load bending moment amplitude coefficient at ultimate to be proposed. [ABSTRACT FROM AUTHOR]

This study investigates the effects of near- and far-fault ground motion on the seismic behavior of historically inclined minarets. Inclined minarets built in Aksaray and Sivas, Turkey, are selected as numerical applications. The top of the Aksaray and Sivas minarets is 1.30 m and 1.23 out-of-plumb and the inclination values are 2.45° and 1.97°, respectively. Firstly, 3D finite element models of the minarets are created using solid elements by SAP2000 software and the numerical dynamic characteristics are determined numerically. 1992 Erzincan and 1999 Kocaeli earthquakes as near- and far-fault ground motion records are selected for the analyses. Maximum displacements, base bending moments, base shear forces, and principal stresses are determined using the finite element method. The results obtained for both earthquakes are compared with each other. It is clearly seen that near-fault ground motion has resulted in much larger response values for both minaret models when compared with far-fault ground motion and max stresses that occurred on the transition segments. [ABSTRACT FROM AUTHOR]

This study aims to investigate the one-way cyclic lateral responses of piles in sloping ground by means of experimental and theoretical analyses. For this purpose, a series of laboratory model experiments were performed for different cases of cycle number, load amplitude, and slope angle, and lateral static loading tests on both level ground and sloping ground were conducted for comparison. Based on these experimental observations, the effects of cycle number, load amplitude, and slope angle on the pile head deflection and the profiles of bending moment and subgrade reaction are discussed. The pile deflection profile is difficult to measure directly owing to the restriction of experimental conditions, and thus a supplementary finite beam element method (FBEM) is provided to compensate for this deficiency. The comparisons between experimental and theoretical results demonstrate that the FBEM can well predict the pile responses in sloping ground, either under one-way cyclic lateral loading or lateral static loading. [ABSTRACT FROM AUTHOR]

In recent years, the construction of a CFST arch bridge has developed rapidly; however, as a kind of structural system dominated by compression, with the increase of material strength and span, the stability of the main arch of the CFST arch bridge has become more and more important. In this paper, the finite element method is used to analyze the hanger force and the main arch stability of the long-span CFST arch bridge. Combined with the Shenzhen Rainbow Bridge project, the axial force of the hanger, the internal force, and stability of the main arch of the arch bridge are studied. In the establishment of the finite element model, considering the actual operation of the arch bridge, the model simulates the interaction between steel pipe and concrete, it studies the large deformation of CFST arch bridges, and the stress distribution and overall stability of the arch bridge are analyzed. The results show that the main deformation of the CFST arch bridge is the vertical displacement of the deck, and the axial force of most members of the upper arch ribs is greater than that of the lower arch ribs. The axial force and bending moment of the lower arch rib near the arch foot are larger, and the compressive stress of the arch foot is greater than that of other positions. The axial force of the suspender of the arch bridge is the largest at both ends of the hanger and the middle hanger, and the axial force of the other hanger is close to each other, and the axial force changes little under the same case. The buckling modes of the arch are mainly the lateral buckling or flexural buckling of the arch rib outside the plane, which indicates that the vertical stiffness of the arch bridge structure is larger than that of the transverse stiffness. The research results make the load-bearing mechanism of the CFST arch bridge more clear and also provide a certain reference for the design and construction of the CFST arch bridge. [ABSTRACT FROM AUTHOR]

This paper presents the optimization of stacking sequence of composite laminate adherends in an adhesive single lap joint under bending moment in order to minimize the amount of maximum peel and shear stress of the adhesive layer. The effects of different assumptions on the equations of the stress and their results are presented. The adhesive single lap joint is modelled as an adherend-adhesive sandwich panel. The finite element method is used to verify the analytical method and the structure is modelled by ANSYS software version 14. The results of the analytical method and the finite element method are compared, and there was a good agreement between two methods. For the optimization part, the single-objective and multi-objective bees algorithm are used to search for the best and worst stacking sequence with and without permutation. The results of the optimization indicate that the maximum shear and peel stress highly depend on the extensional, coupling and bending stiffness in a way that in the optimum model, adherends have high and almost equal stiffness. In the worst models, there is a huge difference in the stiffness of the adherends causing destructive high stress in the thinner adherend. [ABSTRACT FROM AUTHOR]

This paper presents the study of the behavior of a precast continuous beam-column joint that bases its structural work on the friction by wedge effect. It was used in an industrialized social buildings system with excellent performance and is intended to extend its use to architectural programs for residential buildings, which requires the study of the behavior of the beam-column joint. A computational model calibrated against full-scale test results, based on finite element method (FEM) implemented in the software Abaqus, is used. The present paper aims to evaluate the influence of the geometrical and physical-mechanical parameters on the deformational state of the joint. The geometrical parameters are inclination of the column faces and beam ribs that shape the wedge, and the number of slots on these faces, which contribute to the transmission of bending moments of the joint. The physical-mechanical parameters are the axial load on the column and the compressive strength of the concrete of the wedge that joins the beam and the column. To evaluate this influence, the absolute and relative vertical displacements between the beam and the wedge and the lateral displacement experienced by the wedge are determined, and the statistical analysis of the results are included. The influence of the inclination of the column depression, beam rib faces, and the number of slots on these faces in the development of the wedge effect of the joint is demonstrated. The results also demonstrate the positive influence of the increase in axial load on the development of the wedge effect as well as the need not to use a concrete with a compressive strength greater than 20 MPa in the wedge. [ABSTRACT FROM AUTHOR]

Copyright of Guangdong Architecture Civil Engineering is the property of Guangdong Architecture Civil Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Buried pipelines are an essential component of lifelines. However, they are repeatedly damaged by earthquakes. Fault displacement is a significant cause of damage to buried pipelines. In this study, the response of buried pipelines to reverse fault, normal fault, and vertical dislocation was evaluated using the discrete element method (DEM), which can model the details of the nonlinear behavior of the ground. The characteristics of the deformation, bending moment and axial force of the buried pipe for each fault type are clarified about the burial depth. For comparison, a finite element analysis using soil springs was also performed. The results showed that the response of the buried pipe was significantly different from that of the DEM because the deformation of the ground surface could not be considered in the FEM analysis. For finite element analysis with soil springs for the practical design of buried pipes subjected to fault displacement, it is necessary to improve the model of soil springs. [ABSTRACT FROM AUTHOR]

BACKGROUND: Human bones are characterized by strong nonlinearity and uneven bone distribution. Different elastic modulus assignments lead to great differences in static results. OBJECTIVE: To analyze differences of the three material attribute assigning methods in the numerical simulation analysis of vertebral body. METHODS: Based on the principle of reverse engineering, lumbar L4, L5 and intervertebral disc models were established through image segmentation, and three material attributes were assigned to the vertebral body models: (1) Gray value assignment: Gradient value was assigned by using gray value through Mimics. (2) Homogeneous and gray value mixed assignment: A single elastic modulus was given to the anterior cortical bone of the vertebral body, and gray values were used to give to the cancellous bone of the front end and the pedicle, transverse process and spinous process of the posterior end. (3) Cortical bone and cancellous bone assignment: Two elastic moduli of cortical bone and cancellous bone were used. The finite element model under the three assignment methods was loaded with an axial load of 100-500 N. The bending moments of 2, 4, 6, 8, and 10 N·m were applied to simulate the vertebral body to perform forward flexion, backward extension, left and right lateral bending and left and right rotation. RESULTS AND CONCLUSION: Vertebral body under different loading conditions had obvious differences in axial displacement and deflection angle. Root mean square error analysis showed that compared with the other two methods, data obtained by grey value assignment method were more close to the real experimental data. It did not produce obvious stress step phenomenon in material assignment junction, and could not produce obvious stress concentration phenomenon, was more in line with the mechanical properties of vertebral body. Thus, more accurate statics analysis of the spine can be carried out. [ABSTRACT FROM AUTHOR]

Rotary ultrasonic machining is a cost-effective and precise machining method for hard and brittle materials. Aiming at processing SiCp/Al composites, a rotary ultrasonic grinding spindle is proposed in the present study. Expressions were established to calculate the displacement, rotation angle, bending moment, and shear force of the vibrating elements based on the Mindlin moderately thick plate theory. Combining continuous and boundary conditions of vibrating elements with the proposed expressions, the vibration model and frequency equation of a longitudinal-flexural resonating transformer with a large load were established. Then two transformers were designed according to the frequency equation. The resonant characteristics of the transformers were studied using finite element analysis, impedance analysis, and ultrasonic resonance experiments. The obtained results show that the maximum deviation between the resonant frequency and the design frequency of the transformers was 4.95%. Moreover, the maximum deviation of the positions of the pitch circles was 6.51%. It is concluded that the proposed designs have high accuracy. Finally, the orthogonal single-factor experiments of SiCp/Al composites were performed with and without ultrasound. The obtained results show that introducing ultrasonic vibrations significantly reduces the grinding force and the surface roughness while improving the surface quality of the SiCp/Al workpiece. The present study is expected to provide experimental fundamentals to further improve the structure of the grinding spindle, optimize process variables of ultrasound-assisted grinding, and improve the processing efficiency. [ABSTRACT FROM AUTHOR]

To accurately predict the peen forming effectiveness under different parameters, coverage and paths, a regional averaging method is proposed in this paper. The realistic peening stress is estimated based on the average stress of all nodes in a specific area and introduced into the peening area as the initial stress to obtain the resultant shape of the sheet. On the basis of the saturated peening field, an analytical expression is proposed for calculating the average stress considering the interaction between projectiles. And the bending moment is acquired by integrating the stresses on the cross-sectional indentation. Moreover, a series of finite element models are adopted to obtain the accurate average stress. Using a Python script, the finite element models are divided into several regions and the average stress of each region is calculated separately. Through single- and four-shot models, the average stress field around a single shot and the interaction between shots are investigated. And with random peening models, the quantitative relationship of the average stress with respect to the peening intensity and coverage is revealed. In addition, the averaged stresses are introduced to sheet forming models to predict the peen forming effectiveness. Narrow strip experiments are designed under the same peening conditions as that of the sheet forming models, and the simulated values are in good agreement with experimentally measured resultant curvatures. [ABSTRACT FROM AUTHOR]

Offshore wind energy development is driven by ongoing research and development to determine technological issues connected with offshore wind turbines. A fundamental design difficulty is the offshore wind turbine foundations. By far, one of the most commonly practiced foundation systems is mono helical pile foundations because of their simplicity and resilience. Most of the studies on mono helical piles were focused on granular soils and few studies were on clayey soils. However, mono helical piles in clayey soils under combined loading remain to be examined. Hence, a series of three-dimensional finite element analyses were carried out to predict the uplift and lateral capacity of the helical pile embedded in soft clay. The numerical model is verified using the results from the analytical results and a small-scale laboratory test. The verified model is used to simulate the helical pile behavior under the combined uplift and lateral loading condition considering the pile with a different number of helical plates. The results of the combined loading analyses reveal that the lateral capacity decreased when the pile was subjected to uplift load, and a maximum reduction of 12% is observed in mono helical piles provided with a single plate for an applied 50% of the ultimate uplift load. The influence of uplift load also increased the bending moment of the helical pile. Finally, it is suggested that the helical piles should be designed considering the aspects for combined loading conditions. [ABSTRACT FROM AUTHOR]

The cantilevered leg joint commonly used in modern wood furniture was studied by numerical and experimental methods. A novel joint was proposed and compared with the typical joint commonly used in the cantilevered leg. Both of them were made of beech wood (Fagus orientalis. Lipsky). The experimental results showed that the bending moment capacity of the novel joint was remarkably higher than the typical joints, which confirmed that the novel structure had a better mechanical performance. The numerical analysis was conducted according to GB/T 10357.3 standard, the results showed that the stresses of the typical joint were mainly concentrated on the wooden components, while the stresses of the novel joint were concentrated on the metal connectors. The stress concentration obtained by the finite element method (FEM) was consistent with the failure modes of the experimental tests, which provides a reliable method for evaluating and optimizing the novel furniture structure. [ABSTRACT FROM AUTHOR]

The compression behavior of the lattice-walled tubes under variable strain rates are investigated by numerical simulation, and the stress-strain relationship of the structure under quasi-static loading is theoretically analyzed. The finite element software LS-DYNA is used to simulate the structure established by the beam element, and the critical impact velocity is obtained when the structure collapses layer by layer. According to the plastic hinge theory and considering the combined action of the beam's bending moment and axial force in the structure, the stress-strain relationship of the structure under quasi-static loading is derived and compared with the experimental results. The numerical simulation results reveal that the structure of the single-layer gradient tube(SGC) does not undergo shear deformation under quasi-static and low-speed impact. The critical speed of the gradient square tube(GS) is higher than that of a cylindrical tube. The theoretical model can correctly reflect the mechanical response of the structure under uniaxial compression. [ABSTRACT FROM AUTHOR]

Copyright of Tunnel Construction / Suidao Jianshe (Zhong-Yingwen Ban) is the property of Tunnel Construction Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Tunnel Construction / Suidao Jianshe (Zhong-Yingwen Ban) is the property of Tunnel Construction Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The vertical and horizontal bending of micro-beams subjected to axial compressive and transverse concentrated loadings is a common lateral deformation in micro-/nano-engineering that plays a significant role in the design and optimization of micro-/nano-devices. The present study aims to investigate it using the nonlocal theory. For this purpose, the simplified mathematical model is developed, and the nonlocal differential constitutive equation is applied. Since the mechanical properties of micro-beams are different from those of macro-beams, the non-classical nonlocal bending moment is introduced to improve the classical bending formulation in order to adapt to the vertical and horizontal bending of micro-beams. The effects of the external load, external size, structural stiffness, and internal characteristic scale on the vertical and horizontal bending deformation including the midpoint deflection and critical compression are presented. The present analytical model and results are validated by the finite element method. It is shown that the critical compression decreases with increasing the internal characteristic scale. Moreover, the midpoint deflection varies remarkably with respect to the axial and transverse loadings, structural stiffness, internal characteristic scale, and external size. An obvious nonlocal scale effect is found, in which the internal characteristic scale cannot be neglected compared with the external size. Besides, a threshold value of the structural stiffness is determined, and the connotation of the nonlocal interaction requires that the structural stiffness shall not be lower than that threshold. A mutual restriction between structural stiffness and external loadings is observed in the vertical and horizontal bending. In particular, it is further proved that the classical continuum mechanics can not be used in micro-/nano-scaled mechanics through a strange phenomenon that is contrary to mechanical common sense in the calculation example. The study is expected to be beneficial to the design and application of micro-beams subjected to the vertical and horizontal bending. [ABSTRACT FROM AUTHOR]

Intermediate diaphragms (ID) in bridges with precast girders are intended to improve load distribution among girders. Despite this, their efficacy has been doubted recently due to the complex construction tasks needed to join them to the girders. Accordingly, this work aimed to determine the effect of the number of IDs on the distribution of vertical loads and girders response of a simply supported bridge. Four bridge layouts (0, 1, 2, and 3 IDs) were analyzed using 3D computational grillage models. The load distribution factors from the models were compared to those calculated using the Engesser-Courbon and Fauchart methods to determine the latter's accuracy in capturing the effect of the number of IDs. Moreover, the girders responses under the live loads in the current Colombian and Brazilian bridge design codes were assessed. The results show that the IDs have a more significant effect on the load distribution and deflection of interior girders than the exterior girders. Additionally, increasing the number of IDs reduced the maximum shear and torque while the bending moment and deflections remained nearly constant. [ABSTRACT FROM AUTHOR]

The lower extremity is one of the most difficult parts to protect in a car collision. The purpose of this paper is to determine the injury characteristics of the lower extremities under frontal collisions with different overlaps. The test device for human occupant restraint (THOR) 50th finite element model was used to conduct three collision simulations based on the actual load environment. Then the kinematic responses of the lower extremity like axial force/moment of the femur, and tibial index in frontal collision were compared to analyse the relationship between lower extremity injury and collision overlaps. Results show that the kinematics of the occupant's lower limbs is sensitive to collision overlap rates. As the collision overlap increased, the amplitude of lower limb displacement would decrease. The most serious femoral injury occurred in the 25 % overlap frontal collision. Especially in the left middle femur, the peak axial force reaches 3.2 kN and the peak bending moment reaches 108 Nm. In a full-frontal collision, the risk of femoral injury is serious, which may relate the great vehicle acceleration. The tibia index is not significantly different in frontal collisions with overlap rates. This study can provide a reference for the study of lower extremity injury mechanism during frontal collision. [ABSTRACT FROM AUTHOR]

Aluminum alloy tubes are widely used in various industries because of their excellent performance. Up to now, when the tube is bent, the elastoplastic deformation evolution mechanism of the cross-section has not been clear, and no direct analytical proof has been found. In this paper, based on the bilinear material model assumption, a new mechanical model of tube plane bending deformation is constructed. The analytical model can describe in detail the evolution mechanism of elastic–plastic deformation on the cross-section of the tube after bending deformation, the position of the elastic–plastic boundary, the position of the radius of the strain neutral layer, and the relationship between the bending moment over the section and the bending radius. According to this model, the deformation law of the tube cross-section during bending is elucidated. The results are as follows: (1) the deformation evolution of the cross-section of the bending deformed tube calculated by the analytical model is in good agreement with the finite element model (FEM) of pure bending. (2) By comparing the results of the analytical model with FEM results, and the processing test of the self-designed four-axis free bending forming tube bender, the bending moments are in good agreement. (3) Compared with the bending moments calculated by several other analytical models of tube bending, this model has a relatively small deviation value. [ABSTRACT FROM AUTHOR]

The seismic retrofitting of existing multi-storey multi-bay reinforced concrete (RC) frame buildings by the conversion of selected bays into new RC infilled walls is the subject of this research work. The contribution of dowels that connect a new RC infill wall to the surrounding existing RC frame members was studied through a parametric study. The parametric study was performed by nonlinear response-history analyses of a finite element (FE) model. A two-dimensional (2D) frame was modeled, and analyses were performed to calibrate it using the experimental results obtained from a full-scale experiment. The description of the experiment, the experimental results, and the FE model simulation of the test specimen are presented in Georgiou et al. (2018), Georgiou et al. (2022) and Kyriakides et al. (2015) along with a comparison between the experimental results and the numerical ones. Based on the experimental results it was concluded that the number of dowels used in the experiment resulted in a monolithic behavior of the RC infilled frame. To complement the experimental results and to study the interaction between RC infills and the bounding frame both at the global and local level, a parametric study was performed by reducing the number of dowels starting from a spacing of 100 mm (monolithic) to no dowels. The numerical results of the parametric study show that the number of dowels used in the experimental study can be reduced significantly making the use of this method more attractive. These results also provide a basis for the development of a general model for the design of RC infills in existing RC frames, particularly regarding the connection details of the new RC infill walls to the existing bounding frame. The parametric study of the number of dowels connecting the wall to the bounding frame is presented and conclusions are drawn regarding, among others, the effect on the stiffness of the frame, the top storey displacement, the base shear, the axial and shear forces in the dowels, as well as the bending moment at the base of the wall and the outer columns. Some observations that can lead to design recommendations are also presented. [ABSTRACT FROM AUTHOR]

Dents are one of the most common defects in oil and gas pipelines that can reduce the load-bearing capacity of pipelines. Compound dents have an even greater impact on the load-bearing capacity. This paper summarizes the latest evaluation methods at home and abroad for dented pipelines. The research status of dented pipeline bearing capacity under typical loads such as internal pressure, bending moment, and axial force is presented in terms of experimental data and finite element analysis. The research suggests that the evaluation of residual strength of dented pipeline needs to be combined with finite element simulation. Full-scale tests on dented high-grade steel pipelines with large diameters under complex loads are needed. Parametric analysis should be carried out to comprehensively analyze the influencing factors and laws of pipeline residual strength. A fitting formula for limit load under different working conditions needs to be determined, to lay a foundation for dented pipeline engineering evaluation and residual strength prediction. [ABSTRACT FROM AUTHOR]

This work presents studies on static aeroelastic shape optimization of aircraft wings subject to large deformations. The physics are captured using a coupled 3D panel method and a nonlinear co-rotating beam finite element model. The wing is defined by a series of airfoils that are parameterized based on the definition of NACA 4-digit airfoils. The method assumes a solid cross section of isotropic material which is representative of foam core wings. Analytic expressions are derived for most of the cross-sectional stiffness properties, while approximations are introduced for the location of the shear center and the torsional stiffness. Optimized designs achieved using linear and nonlinear deformation models are compared and features are discussed. The objective is to minimize drag subject to constraints on geometry, tip displacement, and root bending moment. Results highlight the importance of using nonlinear models to accurately capture changes in wingspan due to large deformations, as even small differences in the wingspan can have a large effect on the induced drag. Non-planar wings with raised and drooped wingtips are also optimized, where drooped wings are found to achieve larger lift-to-drag ratios due to the increase in effective wingspan in the deformed configuration. [ABSTRACT FROM AUTHOR]

This paper presents the dynamic response of soil-piles-mattress-slab and soil-piles-slab systems under seismic loading. In this context, a three-dimensional numerical model using finite elements is proposed; the piles of two systems are embedded in a soft soil. The reinforced soil is surmounted by a load-transfer mattress setup at the rigid piles head level. The piles are embedded in the soft soil and are perfectly connected to a 0.6 m thick slab. The soil-piles-mattress-slab and soil-piles-slab systems are subjected to a horizontal seismic loading. The soil and the mattress are modeled by volume elements, the rigid piles and piles are modeled by beam elements and the slab is by structural elements. The formulation is based on the direct method and the calculations are done considering elastic and elasto-plastic behaviors for the soil mass. The obtained results are compared in terms of horizontal displacements and internal stresses according to the piles length. The obtained results show the effectiveness of the soil-piles-mattress-slab system, the load transfer mattress constituted an energy dissipation zone for the two behaviors. The embedding at the head of the piles induces very high shear forces and bending moments at the level of the pile-structure connection. These efforts could damage the structure. The soil-piles-mattress-slab system eliminates these major efforts at the head of the rigid piles by separating the structure with a mattress. The non-linearity of the ground must be taken into account for further study. [ABSTRACT FROM AUTHOR]

Scour, caused by swiftly moving water, can remove alluvial sediment and soil, creating holes surrounding a bridge component and compromising the integrity of the bridge structure. Such problems can be equally critical for bridges with piers-on-bank bridges subjected to severe storm and flooding issues. In this paper, the Phillips Road Bridge over Toby Creek (35°18′28.2″ N 80°44′16.6″ W, Charlotte, NC, USA), a pier-on-bank bridge with critical/significant local scour holes and deep riverbank erosion cuts was selected as case study bridge. To investigate the scour effect on the bridge with pier-on-bank performance, the scoured area around a single pier is first quantified using a terrestrial laser and then modeled using nonlinear finite element (FE) analysis, where the local scour is modeled as progressive mass losses using the Element Removal (ER) technique. The FE results are compared to the design loading scenario and the results substantiated that the local scouring could cause large deflection and increased bending moment on the bridge pier. [ABSTRACT FROM AUTHOR]

Soil supporting foundations behave in a nonlinear manner at loading close to its bearing capacity. This behavior affects soil pressure distribution and the corresponding stresses in the raft foundation, which differs significantly from considering the soil as elastic linear material. The present research uses the finite element method to study the effect of soil nonlinearity on the behavior of raft foundations subjected to concentrated loads. The analysis is based on the Winkler type of foundation. The analysis considered different values of the average soil pressure to its bearing capacity. The supporting soil was modeled as elastic perfectly plastic material. The effects of soil nonlinearity on the intensity and distribution of soil pressure, punching shear force, and bending moments in the raft are investigated. The effects of the foundation stiffness evaluation factor L·λ on the behavior of rectangular raft foundations were studied. This parameter combines the effects of the modulus of subgrade reaction, raft thickness, modulus of elasticity of concrete, and column spacing, as these parameters are interrelated. The results indicated that considering the subgrade soil as a linear elastic material underestimates punching shear and bending moments compared to modeling the soil as an elastoplastic material. [ABSTRACT FROM AUTHOR]

Improving the cracking resistance of steel-normal concrete (NC) composite beams in the negative moment region is one of the main tasks in designing continuous composite beam (CCB) bridges due to the low tensile strength of the NC deck at pier supports. This study proposed an innovative structural configuration for the negative bending moment region in a steel-concrete CCB bridge with the aid of ultrahigh performance concrete (UHPC) layer. In order to investigate the feasibility and effectiveness of this new UHPC jointed structure in the negative bending moment region, field load testing was conducted on a newly built full-scale bridge. The newly designed structural configuration was described in detail regarding the structural characteristics (cracking resistance, economy, durability, and constructability). In the field investigation, strains on the surface of the concrete bridge deck, rebar, and steel beam in the negative bending moment region, as well as mid-span deflection, were measured under different load cases. Also, a finite element model for the four-span superstructure of the full-scale bridge was established and validated by the field test results. The simulated results in terms of strains and mid-span deflection showed moderate consistency with the test results. This field test and the finite element model results demonstrated that the new configuration with the UHPC layer provided an effective alternative for the negative bending moment region of the composite beam. [ABSTRACT FROM AUTHOR]

The research on the dynamic response and influencing factors of shield tunnel lining under earthquake demonstrates significant engineering value in guiding the design of antiseismic tunnels. In this paper, a nonlinear finite element model of soil-tunnel interaction is established based on FLAC finite difference software, and then Mohr–Coulomb elastoplastic model and dynamic plastic damage model are used to simulate the dynamic characteristics of soil and lining damage of tunnel, and the seismic waves of South Iceland are selected to analyze the residual internal force, dynamic internal force distribution, and the relative deformation of the top and bottom of the arch of the shield tunnel under the earthquake load. Meanwhile, the effects of depth tunnel, lining thickness, and tunnel diameter on the dynamic response of the tunnel are discussed. In addition, the interaction law of horizontal parallel tunnel and the amplification effect on the surface acceleration are also studied. The results show that under the action of a strong earthquake, the bearing capacity of the tunnel decreases sharply, the lining is destroyed, and a large residual internal force appears. When the buried depth of the tunnel is small, the nonlinear effect is more significant, and the R value increases at first and then decreases with the increase in the seismic acceleration. The maximum dynamic bending moment and maximum dynamic axial force of the tunnel lining aggrandize obviously with the increase in tunnel diameter and lining thickness. In particular, the dynamic bending moment has internal force redistribution and deflection under the condition of large tunnel diameter and small lining thickness. Moreover, the interaction of parallel tunnels affects the distribution of internal force and the magnitude of adjacent surface acceleration. [ABSTRACT FROM AUTHOR]

The lateral deformation behaviour of inclined piles in calcareous sand is investigated with model testing and numerical analysis. A model pile is instrumented with quasi-distributed strain sensors and installed in calcareous sand with various inclination angles. The lateral deformation, bending moment and shear force of the pile are analysed by investigating the effect of the inclination angle and embedded depth. The experimental results of piles with inclination angles of −30°, 0° and 30° are analysed. A random finite element method (RFEM) is established to investigate the effect of the pile inclination. A single exponential function is used to characterize the spatial autocorrelation of soil parameters. A random field is obtained by the Cholesky method. The RFEM is verified with experimental results and used to further analyse the lateral deformation behaviour. The results indicate that both of the orthogonal maximum influence distances from the pile centre have a linear relationship with the pile inclination. A linear relationship between the maximum lateral deformation on the pile top and the pile inclination is proposed. The outcome of this study may be helpful for understanding the lateral deformation behaviour of piles in calcareous sand and designing inclined piles. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Harbin Institute of Technology. Social Sciences Edition / Haerbin Gongye Daxue Xuebao. Shehui Kexue Ban is the property of Harbin Institute of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Guangdong Architecture Civil Engineering is the property of Guangdong Architecture Civil Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This article aims to describe an automatic calculation algorithm developed for the analysis of reinforced concrete and / or prestressed concrete cross sections. The sectional analysis consists in the generation of two characteristic curves: the bending moment - curvature (M-1/r) and the axial force - bending moment (N-M), the calculation approach and the implementation of the algorithm being briefly described by the mathematical equations used. To verify the calculation algorithm, the results were compared with those obtained from experimental tests in the laboratory but also with numerical simulations using commercial computational software based on the finite element method (FEM). The algorithm was written in the MATLAB programming language. The results obtained with the developed algorithm show conservative results when compared to the experimental ones. Moreover, the bending moment resistance for prestressed concrete columns using bonded tendons is better estimated with at least 10% when compared with the one obtained with a fiber based cross section nonlinear analyses. [ABSTRACT FROM AUTHOR]

The single pile is a structural element that has an important role in supporting any part of the superstructure. This paper adopted three dimensional finite element modelling by using ANSYS to discover the influence of soil size domain on pile diameter, pile length, load eccentricity and torsion magnitude. One type of soil was used and described by Drucker-Prager model. The numerical analysis has been performed to show how the variation in soil size domain effects on the behaviour of single pile under torsion load. The procedure which is adopted in the investigation depends on fixing all variables and changing one variable to show the impact of this variable on the pile response considering soil domain variation. From the investigation, it is obvious that the pile diameter, eccentricity and torsion load have a major influence on the pile response, while the pile length has a minor influence on the pile response. Here, the increase in pile diameter reduces the load transfer to the soil; also the increase in eccentricity increases the load transfer to the soil while the increase in soil domain reduces the pile response. When the torsion load increases the pile response increases too. The pile response refers to displacement, rotation, shear force and bending moment. [ABSTRACT FROM AUTHOR]

This paper presents an analytical method to predict the response of a strip foundation building to shallow tunneling based on the two-stage method. The existing building is simplified as a Euler–Bernoulli beam resting on the Pasternak model. The tunneling process and different relative positions between the tunnel and the existing building can be considered in the proposed method. The accuracy of the proposed method is verified through comparisons with results from the finite element and finite difference methods. The results indicate that the differential settlement of the building reaches a maximum and the rotation angles are symmetric with respect to the building centerline when the tunnel face arrives at the middle of the building. The maximum bending moments occur at the middle of the building, while the maximum shear forces occur at about one-fifth and four-fifths of the building length when the tunnel face is located at the two ends of the building. According to the parametric analysis, the alignment angle, elastic modulus and Poisson's ratio of the soil, bending stiffness, and gap parameter greatly affect the building response. [ABSTRACT FROM AUTHOR]