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The overall reinforcement of soft soil foundation has the disadvantages of large engineering quantity and high cost. When the pile foundation bears horizontal loads in the soil, the mechanical properties of the soil near the surface have a greater impact on it compared to the deep soil. Therefore, studying the influence of shallow soil reinforcement on the horizontal bearing capacity of pile foundations has important engineering significance. Studying the influence of shallow soft soil reinforcement around piles on the horizontal bearing performance of piles is of great significance for improving the economic efficiency of pile foundation reinforcement technology in soft soil areas. In this paper, seven pile-soil finite element models are established based on ABAQUS 2022 software to study the influence of shallow reinforcement on the horizontal bearing capacity of single pile. The models were established on the basis of a field test and its validity was verified. The influence of different reinforcement degrees on the horizontal bearing capacity of piles is analyzed by taking the reinforcement width and reinforcement depth as variables. The results indicate that shallow ground improvement significantly enhances the horizontal bearing capacity of the pile. The horizontal bearing capacity of the pile is increased by 83.0%, 104.3%, and 224.4%, respectively, corresponding to a reinforcement width of 2 times, 3 times, and 4 times the diameter of the pile, respectively. With the increase of the reinforcement width, the bending moment and deformation of the pile under the same horizontal load decrease significantly, while it has no significant effect on the location of the maximum bending moment of the pile. The bearing capacity of the pile foundation gradually increases with the increase of the reinforcement depth. Compared with the unreinforced situation, the horizontal bearing capacity of the pile body is increased by 224.4%, 361.3%, and 456.8%, respectively, corresponding to a reinforcement depth of 0.1 times, 0.2 times, and 0.3 times the pile length. As the reinforcement depth increases, the corresponding increase in bearing capacity does not increase linearly, but gradually decreases. This indicates that blindly carrying out deep soil reinforcement without comprehensive evaluation is not advisable. [ABSTRACT FROM AUTHOR]

To simulate the influence of rainfall on the internal forces of expansive soil slope retaining structures, an approximate calculation method for the humidity stress field of expansive soil is proposed in this study. Considering both rainy and non-rainy conditions, on a high expansive soil slope, a numerical model is constructed for a combining supporting structure, which is composed of upper and lower anti-sliding piles and anchor rods/cable frames. Furthermore, the distribution of internal forces in the retaining structure is studied, and design optimization is performed. The research findings reveal that the bending moment profile along the longitudinal axis of the lower anti-sliding pile demonstrates a distinctive "W" pattern, which is characterized by initial reduction, following augmentation, a subsequent reduction, and final amplification. In contrast, the upper anti-sliding pile experiences an ascending trend, followed by a descending trend, and then a subsequent ascending trend. Interestingly, the introduction of rainfall grants an escalation in both the shear force exerted along the entire length of the upper and lower anti-sliding piles and the bending moment encountered by the lower anti-sliding pile. The determination of the internal force distribution of the expansive soil slope retaining structures under different conditions, using the proposed calculation method, provides a further optimization in their design. [ABSTRACT FROM AUTHOR]

In the context of wind turbine pitch control for load alleviation or active wake mixing, it is relevant to provide the time- and space-varying wind conditions as an input to the controller. Apart from classical wind measurement techniques, blade-load-based estimators can also be used to sense the incoming wind. These consider blades to be sensors of the flow and rely on having access to the operating parameters and measuring the blade loads. In this paper, we wish to verify how robust such estimators are to the control strategy active on the turbine, as it impacts both operating parameters and loads. We use an extended Kalman filter (EKF) to estimate the incoming wind conditions based on the blade bending moments. The internal model in the EKF relies on the blade element momentum (BEM) theory in which we propose accounting for delays between pitch action and blade loads by including dynamic effects. Using large-eddy simulations (LESs) to test the estimator, we show that accounting for the dynamic effects in the BEM formulation is needed to maintain the estimator accuracy when dynamic wake mixing control is active. [ABSTRACT FROM AUTHOR]

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As basic structural components of the ship hull, stiffened plates suffer both thrust and shear loads while ships sail in rough sea environments. In order to guide the scaled model design effectively, the similarity law is investigated in this paper. The parameters that determine the nonlinear behaviour of the stiffened plate under compression and shear loading are defined and the nonlinear similarity method is improved. This method is applied to design a scaled model under combined bending and torsional moment, and the collapse test is conducted to research the collapse characteristics. The collapse behaviour of actual ship structures under combined loads predicted by the model test is compared with that obtained by the nonlinear finite element analysis. The good agreement represents the capability of the newly improved nonlinear similarity law. The present research provides a proper way to investigate the collapse characteristics of actual ship structures through a model test. [ABSTRACT FROM AUTHOR]

The suspended monorail is a new mode of rail transit with light weight, medium speed and low cost. It has a lightweight and aesthetically pleasing structure but has obvious limitations when spanning obstacles such as rivers and valleys. From the perspective of structural force and operational safety, this paper puts forward a new composite beam structure scheme, in which track piers and track beams are erected on the main beam of a cable-stayed bridge, overcoming the limitations of conventional suspended monorail spanning ability. To investigate the complex force situation and the load transfer path at the junction of the main beam of the cable-stayed bridge and the track beam piers, finite element models of steel box girder section and concrete box girder section were established using ANSYS software. The results showed that, in the steel box girder section, the pier load was mainly transferred to the diaphragm and the middle web directly connected to it. Among them, the diaphragm load experienced relatively uniform stress, while the middle web's stress was mainly concentrated within a 2-meter radius centered around the pier, which could be mostly transferred to the steel girder bottom plate. 58% of the pier's axial force was transferred to the directly connected diaphragm. During the transfer of the pier column's transverse bending moment, 58. 8% of the shear force was transferred to the directly connected diaphragm. During the transfer of the pier column's longitudinal bending moment, 53. 4% of the shear force was transferred to the middle web. In the concrete box girder section, the pier load was mainly transferred to the concrete web and diaphragm directly connected to it. The concrete stress was mainly concentrated within a 2-meter radius centered around the joint surface, and the pier load was basically transferred within about 0. 5 meters below the joint surface. 68. 8% of the pier's axial force was transferred to the directly connected diaphragm. During the transfer of the pier column's transverse bending moment, 86. 4% of shear force was transferred to the directly connected diaphragm. During the transfer of pier column's longitudinal bending moment, 44. 6% of shear force was transferred to the middle web. [ABSTRACT FROM AUTHOR]

Purpose: To concurrently assess and compare the fixation efficacy, invasiveness, and fusion potential of a posterior integrated transfixation cage system to the posterolateral threaded implant and lateral triangular rod systems, in a cadaveric model. Methods and Materials: Twelve (12) cadaveric sacroiliac joint specimens were utilized and tested within the single-leg stance multidirectional pure moment bending model. Each specimen was tested in the intact, destabilized, treated (using posterior, posterolateral, and lateral systems), and post-fatigue conditions by applying 0 to ± 7.5 Nm of moment in flexion-extension, axial rotation, and lateral bending while measuring the angular range of motion between the sacrum and ilium. Computational models were reconstructed from Computed Tomography (CT) scans and manufacturer surgical technique guides. The models were utilized to quantify the volume of bone removed during implantation and the surface area available for fusion. Results: The posterior integrated transfixation cage system and the lateral triangular rods produced equivalent motion reduction in all motion planes (P > 0.583). The posterolateral cylindrical threaded implant produced less motion reductions than the posterior and lateral implants in flexion-extension (6% ± 3% vs 37% ± 10% and 33% ± 11%, respectively, P < 0.05). The posterior system removed 22%-60% less bone volume from the sacrum and ilium (P< 0.10), introduced 200%-270% more implant surface to the joint space (P< 0.01) and decorticated 75%-375% more joint surface area (P< 0.01). Conclusion: The posterior integrated transfixation single-implant cage system is superior to the posterolateral cylindrical threaded single-implant system. Its performance in osteopenic bone is equivalent to the lateral triangular rod system in healthy bone; however, the posterior integrated transfixation cage system requires a single implant, while the lateral triangular rod system requires three. The posterior implant removes the least bone volume and has the most surface area for fusion, providing a significantly better opportunity for robust sacroiliac joint arthrodesis. [ABSTRACT FROM AUTHOR]

This paper presents an arch structure called the circular box arch with sinusoidal corrugated webs (CBASCW). This study investigates the out-of-plane elastic buckling behavior and elastoplastic stability capacity of the arch through a combined approach of theoretical derivation and finite element simulation. The section stiffness of the arch, including flexural stiffness, shear stiffness, and torsional stiffness, is achieved through theoretical derivation. Additionally, the elastic buckling load in both pure compression and pure bending states is derived. A simplified model is also introduced, which can conveniently simulate the internal force and deformation of the arch. The elastoplastic instability mechanism and failure mode are studied under various loading conditions, including uniform radial load, end bending moment, vertical load uniformly distributed in full-span, and vertical load uniformly distributed in half-span. Furthermore, the stability curves of the arch under conditions of pure compression and pure bending are graphed by incorporating stability coefficient and regularized slenderness ratio. According to the simulation results obtained from the simplified model and the analysis of stability curves, a design formula for stability capacity is proposed. [ABSTRACT FROM AUTHOR]

Concrete shells, designed with near optimal shapes for uniform gravity loads, can be subjected to nonmembrane effects caused by nonuniform and asymmetrical loads. In this paper, a numerical study on the effect of normative loads on a thin triangular concrete shell with three supports is presented. Two actions were considered, wind and snow, which present high spatial variability in both intensity and direction, assuming the values established in Eurocode 1 for the worst possible location, in Portugal. Linear, nonlinear and stability analyses were performed using the ABAQUS software. Results suggest that the wind action, but especially the exceptional snow load in drifted arrangement, produce significant bending moments, leading to decompression, and eventually to the development of stresses above the tensile strength of current concrete classes. Therefore, the production of these shells by assembling prefabricated un‐reinforced modules, requires the use of ultrahigh‐performance fiber reinforced concrete, combined with prestressing. [ABSTRACT FROM AUTHOR]

AbstractA series of 3D finite element analyses were performed to examine the influence of loose sand layers on the monotonic lateral capacity of an extra-extra-large semirigid monopile in dense sand. The SANISAND-04 advanced constitutive model, which was meticulously calibrated, validated and verified using triaxial compression tests, centrifuge tests and a numerical study based on field tests, was adopted for this study. The impact of loose sand layers on monopile response is discussed in terms of its mode of deformation, critical lateral capacity, bending moment, shear force and soil resistance. Results show that the magnitude of the reduction in the monopile lateral capacity is dependent on the thickness and depth of the loose sand layer. Presence of loose sand at the tip of the monopile is also shown to have a significant effect on its lateral capacity. [ABSTRACT FROM AUTHOR]

In offshore pile engineering, the installation of jacked piles generates compaction effects within soil, thus further affecting previously installed adjacent piles. This study proposes a three-dimensional numerical model for pile group installation, soil consolidation, and loading analysis. Subsequently, the effect of pile spacing and pile length-to-diameter ratio on the deformation, internal forces, and vertical bearing capacity of adjacent piles are investigated. The results indicate that with an increase in pile center distance, the peak lateral displacement of the adjacent piles decreases, whereas the peak vertical displacement increases. As the pile length-to-diameter ratio increases, the peak vertical and lateral displacements of the adjacent piles are enhanced. In addition, the peak axial force of the adjacent piles initially decreases and then increases with the penetration depth of the subsequent pile, whereas the peak bending moment initially increases and then decreases. The vertical bearing capacity of the subsequent pile is significantly superior to that of the adjacent piles. Therefore, the effects of pile installation on adjacent piles should be included in pile engineering. The impact of the subsequent pile installation on the bearing capacity of adjacent piles can be significantly reduced by increasing the pile center distance and pile length-to-diameter ratio. The findings provide useful guidance for pile group engineering. [ABSTRACT FROM AUTHOR]

This article presents a study of the wind-resistance and seismic behavior of steel frame elevator structures with square hollow section (SHS) members. The study was conducted by numerical analysis, it begins by examining the semi-rigid performance of SHS T-joints (beam-column joints) under in-plane bending moment, proposes a semi-rigid connection model for the joints, and then investigates the influence of semi-rigid joint effect on the performance of the steel elevators. Finite element (FE) results showed that the semi-rigid model can predict the moment-rotation response of the beam-column joints. The results also showed that the natural vibration period of the elevator with semi-rigid joints is 20% higher than that of an elevator with rigid joints. The semi-rigid joint effect causes the lateral drift of the elevator to increase by more than 47% under wind load, causing the maximum story drift of the elevator to exceed the limit specified in the current code. The semi-rigid joint effect causes the lateral displacement of the elevator to increase by approximately 15%-30% under the seismic waves of a rare earthquake. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the mechanical performance of patient‐specific prefabricated temporary shell versus laboratory‐fabricated CAD/CAM provisional restorations on titanium temporary abutments, with and without thermo‐mechanical ageing. Materials and Methods: Implants with a conical connection were divided into four groups (n = 24) and restored with temporary shell or laboratory‐fabricated central or lateral incisor PMMA restorations that were relined or bonded on titanium temporary abutments. The diameter of the central and lateral incisor groups' implants was regular (ϕ 4.3 mm) or narrow (ϕ 3.5 mm), respectively. Half of each group's specimens were subjected to ageing, simultaneous thermocycling (5–55°C) and chewing simulation (120,000 cycles, 50 N, 1.7 Hz) resulting in eight groups in total (n = 12). The aged specimens were evaluated with optical microscopy, and survival and complication rates were determined according to modified USPHS criteria. The non‐aged specimens and those that had survived ageing were loaded until failure, whereupon bending moments were calculated. Results: Survival rates after ageing were 100% for all groups. Apart from wear facets (ϕ 2–3 mm) on the palatal restoration surface, no complications were observed. The mean fracture load and bending moments ranged between 597.6–847.1 N and 433.3–550.6 Ncm, respectively, with no significant differences between the eight groups (p =.25; p =.20). Conclusions: As patient‐specific temporary shell central and lateral incisor provisional implant‐supported restorations are mechanically stable enough to withstand clinical bite forces, even after thermo‐mechanical ageing, they may serve as an alternative to laboratory‐fabricated provisional restorations. [ABSTRACT FROM AUTHOR]

Concrete beam under pure shear load conditions The shear force capacity of reinforced concrete components is usually investigated experimentally by subjecting the test specimens to vertical loads. These loads induce internal forces in the form of bending moments and shear forces. However, these internal forces cannot be controlled independently under such loading conditions. This article presents a test set‐up that allows a constant bending moment and a constant shear force of any magnitude to be generated in reinforced concrete beams. The loading situation to generate a constant shear force in a beam with a rectangular cross‐section was realized in three component tests. In addition, an FEM model was developed for comparative calculations. The component tests showed a brittle failure. With regard to the load‐displacement behavior and the calculated load‐bearing capacities, there was good agreement between the component tests and the corresponding FEM simulations. The test setup presented here is generally considered suitable for generating a state of pure shear force in reinforced concrete beams. [ABSTRACT FROM AUTHOR]

This research aimed at studying the effect of fiber content on the flexural strength and behavior of steel fiber reinforced concrete (SFRC) beams with steel rebars. The study employed finite element (FE) analysis to simulate the behavior of SFRC beams. The simulation results of the FE model were validated against experimental data. Subsequently, the validated model was utilized to analyze the strength and crack patterns of SFRC beams with steel rebars in comparison to conventional RC concrete beams without fibers. The parametric study indicates an average 9% increase in RC beam capacity for every 1% increment in fiber volume fraction. Moreover, this study reveals more substantial effects of steel fibers on beams with low reinforcement ratios. Crack analysis shows that cracks in the SFRC beams are distributed more evenly compared to plain RC beams at regions with the same bending moment, indicating enhanced strength to sustain loads, reduced deflection, and improved beam ductility. [ABSTRACT FROM AUTHOR]

Considering the assembly as a multi-span, continuous beam-column, a system of "three moment equations" can be derived to compute side force components as well as all reactive forces, deflection, bending moment, and slope. Solving high-order nonlinear equations involves programming and debugging, which can be time-consuming. Moreover, many methods for solving such equations may not necessarily yield correct results. However, the Python open-source library "sympy" simplifies this process by eliminating the need for complex programming and debugging. It only requires the necessary equation information to quickly solve the high-order nonlinear equations. Additionally, C# provides the capability to rapidly create graphical user interfaces, enhancing the solution's usability. By utilizing Python.NET to call Python code, it reduces the programming workload and effectively addresses the problem of solving a system of three moment equations. [ABSTRACT FROM AUTHOR]

This paper investigates the bending fracture problem of a micro/nanoscale cantilever thin plate with surface energy, where the clamped boundary is partially debonded along the thickness direction. Some fundamental mechanical equations for the bending problem of micro/nanoscale plates are given by the Kirchhoff theory of thin plates, incorporating the Gurtin-Murdoch surface elasticity theory. For two typical cases of constant bending moment and uniform shear force in the debonded segment, the associated problems are reduced to two mixed boundary value problems. By solving the resulting mixed boundary value problems using the Fourier integral transform, a new type of singular integral equation with two Cauchy kernels is obtained for each case, and the exact solutions in terms of the fundamental functions are determined using the Poincare-Bertrand formula. Asymptotic elastic fields near the debonded tips including the bending moment, effective shear force, and bulk stress components exhibit the oscillatory singularity. The dependence relations among the singular fields, the material constants, and the plate's thickness are analyzed for partially debonded cantilever micro-plates. If surface energy is neglected, these results reduce the bending fracture of a macroscale partially debonded cantilever plate, which has not been previously reported. [ABSTRACT FROM AUTHOR]

The load transfer mechanism of laterally loaded pile groups is very complicated, and the analysis method is affected by many factors. This paper presents a field test study on lateral responses of large diameter cast-in-place isolated single piles with free head and pile groups with fixed head to investigate the pile group effect. Boreholes are drilled, and relevant field and laboratory tests are carried out to obtain main physical mechanical parameters and the soil profile of the site. Results of lateral loads, lateral displacements and bending moments measured in the field are reported and discussed. A group efficiency factor-based calculation method applicable to laterally loaded pile groups is derived according to a series of full scale and centrifuge tests. An existing group efficiency factor-based calculation method is compared with the proposed method. And three other measured test results are used to verify the calculated results. The comparison results show that the proposed method provides good predictions of load–displacement responses of pile groups. [ABSTRACT FROM AUTHOR]

In the realm of constructing urban underground spaces, it is imperative to address the impact of tunnel leakage on the surrounding environment. This paper introduced a theoretical analysis to investigate the localized water leakage's influence on adjacent pile foundations. A pore pressure distribution function, accounting for localized leakage water, was formulated. Integrated with the seepage control equation, this function facilitated the calculation of additional stress imposed on piles due to tunnel localized water leakage. Employing the Pasternak foundation model, an analytical solution was developed to assess the lateral performance of adjacent piles under localized water leakage conditions. This approach was compared with numerical simulations to validate the reliability of soil seepage fields and pile lateral performance resulting from localized tunnel leakage at different positions. Through comprehensive parameter analysis, it was observed that the width of the leakage joint significantly influenced pile lateral responses, manifesting in three distinct stages: linear increase, nonlinear gradual augmentation, and stabilization. Different positions of the lining leakage joint yielded varying effects on adjacent piles' lateral responses, with closer proximity intensifying the impact on the pile. When leakage joints were situated near the pile toe, a pronounced negative bending moment was generated. Furthermore, this study summarized the influence range of tunnel localized leakage adjacent to piles. It established that the maximum pile-tunnel horizontal distance inducing lateral pile responses due to tunnel localized leakage was set at 8 times the pile diameter (8 Dp). Additionally, tunnel leakage influences should be considered when the pile length exceeded 0.6 times the depth of the tunnel axis. [ABSTRACT FROM AUTHOR]

Together with axial and flexural actions, modern-designed reinforced-concrete walls can also be subjected to torsion during rare loading events, such as large-magnitude earthquakes or strong winds. For certain widely used nonplanar open cross-section geometries, this torque is resisted primarily through warping. In some cases, the longitudinal stresses caused by torsional warping can be of the same order of magnitude as those caused by flexure, which postulates a reduction of the in-plane bending moment capacity of the section. This study explores the reduction of bending moment capacity of open reinforced-concrete U-shaped core walls due to the simultaneous application of flexural, axial, and torsional loading. Initial investigations focused on strain gradients through the wall segments of reinforced-concrete U-shaped walls. Using a refined data set from a recent experimental campaign, the commonly assumed linear strain gradient used in the design of reinforced-concrete walls is challenged. Numerical methods that intrinsically rely on the observed strain gradients are then employed to compute, for a range of torque-to-bending-moment ratios, the ultimate bending moment and torque capacities from combined loading scenarios. The numerical results corroborate existing experimental results, indicating a significant reduction (almost half) in ultimate bending moment capacity when a torque equal to approximately 20% of imposed bending is applied. Interaction diagrams between the ultimate torque and bending moment show that it is possible to derive a simple relationship between the two for the purposes of structural design. These results can help formulate guidelines for future international building codes, which in their current form cannot account for the design of open sections governed by warping torsion. [ABSTRACT FROM AUTHOR]

Angle profiles belong to the most common steel profiles used in several types of civil engineering structures, such as in lattice towers. Although, in such towers, they are usually considered as axially loaded (truss) members, an additional bending moment develops due to the eccentricity between the point of load application and the gravity center of the profile. Therefore, this paper focuses on the buckling resistance of single-angle members subjected to combined compression and bending. The investigations have been performed through numerical parametrical studies and have been compared to different normative documents where interaction equations are provided. [ABSTRACT FROM AUTHOR]

In general, pile foundations are utilized to support structures like tall buildings, bridges, and transmission towers, which are frequently subjected to lateral stresses initiated by wind, action of waves, earthquakes, or traffic loads. Several high-rise structures, highway and railroad overpasses, as well as transmission towers, are constructed near slopes and rely on pile foundations for support. Due to the effects of wind and waves, pile foundations are continuously subjected to cyclic loads. For piles supporting tall buildings, transmission towers, offshore structures, or infrastructure in seismic zones, 1-way or 2-way cyclic lateral loads are commonly applied. Therefore, while designing pile foundations, it is essential to understand how piles behave laterally when they are located near a sloping crest. One of the primary challenges in ensuring the efficient functioning of the superstructure is analyzing how the soil and foundations respond when exposed to long-term lateral loads, such as wind, over an extended period on the piles of offshore platforms. Because of the presence of slope, the pile's lateral load capacity decreased due to the reduced ability of the soil to provide passive resistance. This paper presents small-scale 1-g model tests conducted on the sand to assess the loss of pile's lateral capacity when subjected to 100 cycles under 1 and 2-way cyclic loading. The Relative Density (60%) and varying slopes (Horizontal ground, 1V:3H) with varying spacing (5D and 7D) and aspect ratios (L/D) of 25 and 40 were implemented in this study. Cyclic lateral load tests were performed for sloping as well as horizontal ground. A major reduction in lateral capacity, exceeding 60%, was observed due to the application of cyclic loading. Moreover, the transition from horizontal ground (HG) to sloping ground (SG) decreased the maximum bending moment by 25–40%. This study exemplifies the piles' behaviour when subjected to cyclic lateral loading while resting on a sloping crest, which represents a critical scenario in pile foundation design. [ABSTRACT FROM AUTHOR]

Exploring fire resistance of high strength steel end-plate connections is one of the key technical bases for fire resistance design and fire safety assessment of high strength steel structures. Numerical simulation and parameter analyses of high strength Q690 steel flush end-plates will contribute to a reasonable design of high strength flush end-plate connections. In this paper, a finite element model of high strength steel flush end-plate connection considering thermal creep effect was established and validated by experimental results. The thermal creep finite element model can simulate accurately heat performance, failure modes and deformations of high strength flush end-plate connections at elevated temperatures. The increase of axial compression ratio has little effect on rotation, deflection, failure time, critical temperature, and critical rotation with elevated temperatures. The increase of bending moment ratio has little effect on the development trend of rotation and deflection. Proper increase of thickness of the end-plate can improve failure time and critical rotation, and the increase range is within 7% and 36% respectively. Proper increase of diameter of bolt can improve failure time, critical temperature, and critical rotation to a certain extent, and the increase range is within 10%, 6% and 27% respectively. Proper increases of thickness of the end-plate and diameter of bolt will improve the fire resistance of flush end-plate connection. [ABSTRACT FROM AUTHOR]

In this research, the potential benefits of using various structural types of cemented soil, including block-type, column-type, and wall-type, to reinforce the active zone behind a quay wall were investigated by experimental and numerical methods. The response of the quay wall and ground was analysed from aspects of soil movement, quay wall displacement, lateral earth pressure, and bending moment, and a close agreement between the experimental and numerical results was observed. Experimental and numerical results showed that the cemented soil effectively prevented potential deep soil sliding, and then lateral displacement of the quay wall and ground deformation was reduced. Among various structural patterns, the case with the block-type cemented soil exhibited smaller lateral earth pressure on the quay wall, while the case with the wall-type cemented soil more effectively reduced the bending moments and lateral displacements of the quay wall; therefore, wall-type cemented soil seems to be more favourable considering their improved performance under the same load intensities and excavation depth. This research provides a hint and guideline for the preliminary design of cemented soil-stabilised sheet pile quay structures in soft clay based on the lateral load-reduction effect of the varying structural types of the cemented soil. [ABSTRACT FROM AUTHOR]

A new grouting technique, double-row capsule grouting (DRCG), has been developed and implemented in practice. This grouting technique could effectively mitigate excavation-induced tunnel movement and ensure the serviceability of metro lines. However, its control mechanism and the factors that influence its performance are not fully understood. Based on a case history that utilized capsule grouting the precision of the numerical model is validated. Parametric studies are conducted to investigate the influence of the grouting location and volume on the tunnel deformation, bending moment, restoration ratio, and shear strain of the soil. In addition, a comprehensive comparison between the conventional grouting technique and DRCG is performed to illustrate the control mechanism of this innovative technique. The results could contribute to a better understanding of the factors that impact the performance of DRCG and an optimal application of DRCG, which facilitates its efficient implementation and further development in engineering. [ABSTRACT FROM AUTHOR]

In response to the problem of deformation caused by surrounding construction disturbances in existing shield tunnels in soft soil areas, lateral horizontal grouting is often used. Based on an independently designed and developed lateral grouting experimental device, the mechanism of horizontal lateral grouting on the convergence deformation of the tunnel was determined. A three-dimensional finite-element analysis model was established to study the force and deformation characteristics of the tunnel tube sheet, and to verify the correctness of the model test results. The grouting remediation efficiency, η, was introduced to establish the relationship between the grouting volume and the convergent deformation. The results show that the tunnel tube sheet was subjected to asymmetric additional soil pressure along the ring direction, and asymmetric displacement occurred, which was most obvious on the grouting side. The additional moment distribution was symmetrical and spindle-shaped, and the peak bending moments mostly appeared in the arch roof, the arch bottom, and the arch whist. With a continuous increase in grouting volume, the efficiency of the grouting remediation decreased, and the two were negatively correlated. [ABSTRACT FROM AUTHOR]

Uneven settlement of the strata induced by ground fissure activity trigger great damage to a shield tunnel crossing a ground fissure zone. It is of great significance for the safe maintenance of tunnels to accurately predict the mechanical response of the tunnel structure under the dislocation of a ground fissure. In this paper, an analytical solution of mechanical behaviors of a shield tunnel crossing an active ground fissure zone is proposed. The shield tunnel-strata interaction in a ground fissure site is simplified as a Timoshenko beam placed on a Vlasov foundation. The governing differential equation and the closed-form solution for an equivalent shield tunnel subjected to additional load induced by the dislocation of ground fissure are derived. The proposed solution is adopted to analyze the mechanical behaviors of a shield tunnel, including tunnel displacement, rotation, bending moment, and shear force. The results of a model test and a numerical model are provided to verify the rationality of the proposed analytical solutions. Finally, a parameter sensitivity analysis about the additional load forms, the compression and shear modulus of the foundation, and the shear stiffness coefficients of the tunnel are conducted. The result shows that the form and value of the additional load has a large impact on the deformation and a slight impact on the internal forces of the tunnel. The foundation compression modulus determines the constraint effect of the strata, and the deformation and internal force response of a tunnel decrease with the increasing foundation shear modulus. In addition, the increase of shear coefficient enhances the shear stiffness of a tunnel, but largely increases the internal force as well. [ABSTRACT FROM AUTHOR]

Accurate prediction of excavation deformation and stress affects the safety of excavation engineering and the surrounding environment. However, the traditional calculation method ignores the influence of soil shear action and its nonlinear deformation characteristics. Therefore, this paper proposed a coupled analytical method for braced excavation considering the continuity of soil deformation and nonlinear pile–soil interaction. A nonlinear Pasternak two-parameter foundation model was developed based on the Pasternak foundation model and nonlinear p–y curves. The control differential equations for the excavation in the critical and embedded sections were derived. Also, the numerical solutions of excavation deformation and force under different boundary conditions were obtained by the finite difference method and Newton's iteration method. Further, the excavation calculation procedure considering the construction process and nonhomogeneity of soil was suggested. Through finite-element (FE) and engineering case analyses, the traditional calculation method overestimated the excavation deformation and internal force, while the proposed methods were consistent with the measured results. Finally, the effects of soil shear stiffness and initial foundation reaction modulus on the excavation were discussed, and we found that the two parameters had more significant impact on the wall bending moment than displacement. The results provide some reference for the design calculation of braced excavation. [ABSTRACT FROM AUTHOR]

In this paper large deformation of the skew microplate made of laminated composite enhanced with graphene nanosheets is investigated using first shear deformation theory (FSDT) when the plate undergoes combination of mechanical and thermal loads. Halpin-Tsai model is utilised to model mechanical properties while for thermal properties Schapery model is considered. First, shear deformation of the plate was obtained while using Green-Lagrange tensor the non-linear strain of the microplate is extracted using the von-Karman assumptions. Then, by Modified Coupled Stress Theory (MCSD), the components of Cauchy and Couple stress tensors are specified. Finally, using Hamilton Principle the governing equation of the microplate and boundary conditions are computed. After deriving analytical governmental equation results are presented for the simple support boundary condition and the proposed model is validated by previously reported data and it proves to be promising. Primary results showed that with raising skew angle deflection and bending moment decreases which means microplate becomes more rigid in higher skew angles. Higher mechanical loads lead to higher deflections and bending moments. Four different configurations of the layers were analysed from which angle-ply configuration possessed highest deflection and bending while UD configuration revealed the lowest values of deflection and bending moment. [ABSTRACT FROM AUTHOR]

Sensor-based monitoring of process and tool condition in milling is a key technology for improving productivity and workpiece quality, as well as enabling automation of machine tools. However, industrial implementation of such monitoring systems remains a difficult task, since they require high sensitivity and minimal impact on CNC machines and cutting conditions. This paper presents a novel multi-sensory tool holder for measurement of process forces and vibrations in direct proximity to the cutting tool. In particular, the sensor system has an integrated temperature sensor, a triaxial accelerometer and strain gauges for measurement of axial force and bending moment. It is equipped with a self-sufficient electric generator and wireless data transmission, allowing for a tool holder design without interfering contours. Milling and drilling experiments with varying cutting parameters are conducted. The measurement data are analyzed, pre-processed and verified with reference signals. Furthermore, the suitability of all integrated sensors for detection of dynamic instabilities (chatter) is investigated, showing that bending moment and tangential acceleration signals are the most sensitive regarding this monitoring task. [ABSTRACT FROM AUTHOR]

Motivated by a curiosity to explore the behavior of innovative arch structures enabled by the use of fiber-reinforced polymer (FRP) composites, this paper proposes a theoretical model built upon an enhanced formulation of the deflection method, broadening its scope to large-curvature problems. Traditionally, the deflection method approximates curvature as the second-order derivative of deflection, a simplification valid only for small curvatures. This limitation poses a challenge when applying the deflection method to problems involving large curvatures, a characteristic inherent in FRP-enabled arches where significant curvatures arise either initially or due to deformation. The enhanced formulation at the core of the proposed model addresses this challenge by incorporating a circular deflection function. This function posits that each deformed segment of the structural member can be represented by a circular arc, with its curvature and length related to the internal axial force and bending moment at the midpoint section of the segment. This feature facilitates the exact representation of curvature, offering the proposed model a unified approach capable of addressing both small- and large-curvature problems. The paper details the formulation and verification of the theoretical model, with an emphasis on its application to representative cases of FRP-enabled arches. [ABSTRACT FROM AUTHOR]

The pitch bearings of wind turbines are slowly oscillating, grease-lubricated slewing bearings. They facilitate the pitching movements of blades which control aerodynamic loads. These bearings have diameters of several meters, their blade-side sealings can face the environment, bending moment loads can cause radial deformation of the bearing rings, and their highly variable operating temperatures can facilitate condensation of water inside them. All of this makes water ingress into the lubricant possible. There is limited public knowledge with regards to the maximum water content for safe operation in this application. This work presents the results of a series of scaled wind turbine time series tests with both 'dry' (no water contamination) and 'wet' (10 mass % demineralized water added) greases. A set of four commercially available greases were tested. The time series were scaled from wind turbine operation and represented a 13.7 h worst-case scenario of operation with small oscillation amplitudes and no longer lubrication runs in between. Three of the greases showed reduced friction and no or limited raceway damage in the wet condition, whereas one showed increased friction and raceway damages. [ABSTRACT FROM AUTHOR]

Several bridges in Indonesia are designed using elastomeric bearing (ERB) with a low capability of reducing seismic responses. This results in a significant demand for larger pier crosssectional dimensions and a greater number of reinforcements, necessitating the consideration of seismic isolation devices to optimize the pier configuration. Lead rubber bearing (LRB) has been widely used as a seismic isolation device due to the natural period shifting and sufficient energy dissipation, but it costs a lot. A shear panel damper equipped with a gap (SPDG) was proposed regarding its capability to provide high damping at low cost as an alternative device to LRB. This study compared the seismic performance of three structural systems of simply supported prestressed concrete (PSC) box girder bridges. Those were analyzed using Nonlinear Time History Analysis (NLTHA) with the OpenSees software. As a result, both SPDG and LRB increased the structural flexibility and generated similar relative pier responses to the conventional bridge with ERB. For example, SPDG generated the relative responses of the top pier displacement, base shear, and bending moment up to 64.76%, 83.55%, and 65.66%, while LRB was 64.92%, 83.39%, and 66.89%, respectively. Meanwhile, the bridge's structural performance equipped with LRB and SPDG showed a fully operational and operational limit, while the one with ERB reached the life safety limit due to the longitudinal earthquake. The life safety limit due to the transverse earthquake was also observed in the three bridge models. In conclusion, SPDG is applicable in the seismic isolation system as it has a similar performance to the LRB. [ABSTRACT FROM AUTHOR]

Copyright of Railway Construction Technology is the property of Railway Construction Technology 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 Railway Construction Technology is the property of Railway Construction Technology 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 aimed to use numerical modeling to investigate the behavior of soil slopes under various inclination angles of soil nails and surcharge load conditions. Numerical modeling and analysis are performed using finite element software PLAXIS 2D. In this study, the stability of a soil slope is investigated at different soil nail inclination angles, viz., 0°, 5°, 10°, 15°, 20°, 25°, and 30°. A surcharge load of 80 kN/m is applied at distances of 2 m, 4 m, and 6 m from the slope edge. The results show that the safety factor increases with increasing soil nail angle under a constant surcharge load. Similar results were obtained when the distance of the surcharge load increased from the slope edge. In addition, the bending moment and shear forces in the soil nails decreased with increasing inclination of the soil nails and increasing distance of the surcharge load from the slope edge. The slope with nails at 20° is the most stable slope, with safety factors of 1.647, 1.610, and 1.692 for the three surcharge loads. Similarly, minimum shear forces of 2.298, 2.684, and 1.183 kN/m and bending moments of 0.4132, 0.4075, and 0.1236 kN-m/m are predicted when the nails are inclined at 20° for the above three cases of surcharge loading, respectively. [ABSTRACT FROM AUTHOR]

Copyright of Geology & Exploration is the property of Geology & Exploration 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.)

Anchor damage is one of the main risk factors for the safe operation of submarine cables. Additionally, due to a scour effect induced by seabed currents, submarine cables are prone to exposure or even suspension, increasing the risk of being dragged by anchors. Therefore, it is necessary to study the global response of exposed and suspended submarine cables subjected to anchor dragging. In this study, the tensile and bending stiffnesses of submarine cables are calculated by theoretical methods, and the accuracy of these calculations is verified by establishing a detailed finite element model. Then, the mechanical properties of the submarine cables are equivalently modeled using beam elements, and a large-scale finite element model for exposed and suspended cables under anchor dragging is established. Considering different dragging forces, exposed lengths, spanning lengths, and spanning heights, the overall deformation and mechanical responses of exposed and suspended cables are analyzed separately. The results show that under dragging forces, axial forces are uniformly distributed along exposed and suspended segments, while bending moments concentrate at the central hooking area and the ends of exposed and suspended segments. The influence of dragging force, exposed length, spanning length, and spanning height on the stress and deformation of submarine cables is significant. The results can be used for submarine cable damage assessments caused by anchor dragging. [ABSTRACT FROM AUTHOR]

The evidence of soil nonuniformity has been reported in several site investigation reports and is well-confirmed for any soil in general. However, studies related to the spatial soil variability of offshore ground are somewhat limited, and current design practices for monopile foundations also overlook the uncertainty of the offshore ground. This paper presents the probabilistic evaluation of the serviceability limit state of monopile foundations considering the spatial variability of offshore ground. The nonuniformity of the ground is modeled utilizing the site-specific undrained shear strength (su) as a stochastic variable, using a spatially correlated Gaussian random field. A hardening soil constitutive model is utilized in 3D finite element analysis of offshore ground, with a focus on parameter calibration. The reliability of the serviceability limit state is assessed based on the allowable load on the pile head. The stochastic behavior of the maximum bending moment and maximum shear force along the depth of the monopile is also investigated. Besides, the paper also highlights the importance of incorporating ground nonuniformity during the design process of a monopile foundation. [ABSTRACT FROM AUTHOR]

An analytical expression for the strain energy of a constrained extensible Cosserat elastica is developed for general planar shapes and deformations of the rod. This strain energy function naturally couples tangential stretch and reference and current curvatures of the centroidal curve. The model considers a rigid rectangular cross-section of the rod which remains normal to the centroidal curve. The constitutive equations for the tangential force, shear force and bending moment are consistent with a restriction based on the balance of angular momentum that requires a stress-like tensor to be symmetric in a similar manner to the symmetry of the Cauchy stress in a three-dimensional continuum. Examples show that coupling of tangential stretch and reference and current curvatures of the centroidal curve in the new strain energy function can significantly influence predictions of tangential force, shear force and bending moments. [ABSTRACT FROM AUTHOR]

The performance of high-rise reinforced concrete (RC-framed) buildings with shear walls is crucial for ensuring stability, ease of maintenance, and durability. High-rise structural systems are significantly impacted by lateral forces, axial loads, shear forces, base-shear, and the maximum story displacement/drift. This work analyzed a G+20 story RC-framed building in Dehradun, India, under seismic loading. Base shear, maximum story displacement, and bending moment behaviour in structures with and without shear walls were then evaluated. The analysis adhered to the I.S. code 1893:2016 standards and employed SAP2000 software to determine the maximum base shear under specified loading conditions. The findings demonstrated that frames designed with appropriate shear walls exhibit superior performance in absorbing lateral forces, leading to a substantial reduction in displacement values by approximately 30-50%. Moreover, these structures showed enhanced resistance to bending moments throughout the building's height. When properly configured with shear walls, the building's resistance to earthquake forces was improved significantly, with an increase in resistance by about 40-60% compared to structures without shear walls. In conclusion, incorporating shear walls in high-rise RC-framed buildings offers considerable advantages in terms of seismic performance. The reduced displacement and increased resistance to moments and base shear contribute to the overall stability and durability of a building. This study underscores the significance of shear walls in high-rise construction, providing critical insights that can inform the design of intact and highly resilient buildings in seism-prone areas. Moreover, in seismic zones, properly positioned shear walls are essential for RC-framed structures in multi-story building constructions. They help to limit maximum story displacement and bending moments, making the structures safer than those without shear walls. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Architecture & Civil Engineering is the property of Chang'an Daxue Zazhishe 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.)

Longitudinal ordinary rebars are discontinuous at the joints of precast concrete segmental bridges (PCSBs), which can open under tensile stresses induced by bending moments. This will lead to durability issues with the joints. To improve the bending properties of PCSBs, a novel joint type featuring continuous rebars was proposed in the present study. Three specimens were subjected to testing to examine the bending behavior of PCSBs using this new joint design compared to traditional joints. The crack propagation, structural deformation, joint opening width, strain in rebars, failure mode, stiffness, and flexural capacity were comprehensively investigated. The test results reveal that the continuous rebars effectively transferred bending normal stress between joints, ensuring full development of cracks in each beam segment. Effective control of joint opening width was also observed. Compared to traditional joints, the new joints exhibited a 29% to 33% increase in cracking load and a 32% increase in ultimate load. Failure in the continuous rebar joints was characterized by partial anchorage failure of the rebars along with localized concrete crushing in the top compression zone. Based on the test results, a computational method was proposed for calculating the cracking strength and flexural capacity of the new joints. [ABSTRACT FROM AUTHOR]

An innovative form of steel–concrete composite beam, the steel–coarse aggregate reactive powder concrete (CA-RPC) composite beam with uplift-restricted and slip-permitted (URSP) connectors, is introduced in this paper. The aim is to enhance the cracking resistance under negative bending moments, which is a difficult problem for traditional composite beams, and to make the cost lower than using ordinary reactive powder concrete (RPC). An experimental investigation of the behavior of six specimens of simply supported steel–CA-RPC composite beams with URSP connectors under negative bending moments is presented in this paper. The test results validated that the cracking load of steel–CA-RPC composite beams could be approximately three times that of the ordinary steel–concrete composite beams while the bearing capacity and stiffness are almost the same. A numerical model, using the concrete damaged plasticity (CDP) model to simulate the behavior of the CA-RPC material, was proposed and successfully calculated the overall load–displacement relationship of the composite beams with sufficient accuracy compared with the experimental results, and the distribution of cracks and the failure mode of the beams could also be captured by this model. Furthermore, a parametric analysis was carried out to find out how the application of prestress, CA-RPC, and URSP connectors could affect the cracking resistance of the composite beams, and the results indicated that using CA-RPC and prestress made the main contributions and that the usage of URSP could boost the effect of the other two factors. The plastic resistance moment of the beams was also compared with the calculation results using the methods introduced in Eurocode 4, and it was proved that the calculation results were lower than the experimental results by approximately 10%, which meant that the method was reliable for this kind of composite beam. [ABSTRACT FROM AUTHOR]

With the extensive use of a precast segment column in the field of engineering, impact resistance performance has gradually attracted attention, as many accidents have caused huge economic losses and casualties. This study explored the dynamic response and failure modes of a prefabricated segment column both with and without Carbon Fiber-Reinforced Polymers (CFRPs). Firstly, numerical models of a precast segment column and CFRP-wrapped steel column under impact loads were developed, and the modeling method's accuracy was fully verified. Then, numerical models of a bridge precast segment column with and without CFRPs under vehicle collision were established, and the differences in the dynamic performances between the precast segment column with and without CFRPs are explored. Finally, the effects of impact velocity, concrete strength, and CFRP thickness on the dynamic performance of a precast segment column are considered. The results indicate that in the case of a vehicle collision, multiple cross-sectional positions form highly complex stress states. At 100 km/h, the differences in bending moment and shear force values between reinforced and unreinforced precast segment columns at the impact section are 7.6% and 7.1%, respectively. At this velocity, the peak impact force also increases by 15.8% as the local stiffness of the precast segment column increases after reinforcement with a CFRP. The bottom segment of the precast segment column with a CFRP is crushed, and the precast segment column experiences shear failure under vehicle collision. [ABSTRACT FROM AUTHOR]

The dimensions of tenons in solid wood furniture significantly influence the mechanical performance of mortise and tenon joints. While previous studies have primarily focused on tenon length, width, and thickness, they often overlooked the impact of clearance between the mortise and tenon. This study investigates the effects of tenon length, tenon width, and clearance on the mechanical performance of mortise and tenon joints, aiming to enhance their bending moment capacity (BMC) and stiffness. A three-factor, three-level orthogonal test was conducted, utilizing range analysis and variance analysis to assess the effects of each factor on BMC and stiffness. The LSD post hoc test was employed to identify significant differences between levels of the same factor, and nonlinear regression analysis was used to fit the experimental results. Based on orthogonal experiment outcomes, a grey relational theory-based evaluation system was developed to assess the comprehensive performance of joints, including both moment capacity and stiffness. Results indicate that tenon length has the most significant effect on BMC, followed by clearance and tenon width, while clearance has the greatest impact on stiffness, followed by tenon length and tenon width. These findings are consistent with those obtained from grey relational analysis. When considering both BMC and stiffness as a comprehensive evaluation, the optimal combination is a tenon length of 40 mm, a tenon width of 35 mm, and a clearance of −0.1 mm. This study offers valuable insights for the rational design of mortise and tenon joints, contributing to improved performance and reduced manufacturing costs. [ABSTRACT FROM AUTHOR]

Copyright of Hydrogeology & Engineering Geology / Shuiwendizhi Gongchengdizhi is the property of Hydrogeology & Engineering Geology 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 Railway Standard Design is the property of Railway Standard Design 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 Railway Standard Design is the property of Railway Standard Design 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 Railway Standard Design is the property of Railway Standard Design 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.)