Displacement Changes Research Articles

Intelligent identification of moving forces based on visual perception

The task of identifying moving forces presents a challenging inverse problem for bridge health monitoring and condition assessment. Existing methods for identifying moving loads rely on complex structural response measurement equipment, resulting in inefficiency and elevated costs. To address these challenges, this study introduces an innovative intelligent identification method for moving forces on bridges using visual perception techniques. The proposed method utilizes cameras to capture displacement changes at specific points on the bridge surface to reconstruct moving forces in the time domain. Initially, numerical simulations were conducted to ascertain the feasibility and robustness of identifying moving forces based solely on the structural displacement response. This phase also investigates the influence of different measurement point combinations on identification accuracy. Subsequently, the accuracy of the proposed method in measuring the dynamic displacement response of the structure was carefully evaluated by an outdoor shaking table test. Furthermore, a meticulously designed simply supported beam model was fabricated, followed by the execution of precise vehicle-bridge coupling dynamic experiments. This phase rigorously validates the effectiveness and accuracy of the proposed moving force identification method at varying vehicle speeds. The obtained results substantiate the proposed approach's capability not only to comprehensively capture bridge response data for full-area monitoring but also to consistently and reliably identify information on moving vehicle forces. This study underscores a pioneering application of intelligent visual perception technology in the field of identifying moving forces. The introduced noncontact intelligent identification method is an effective solution for monitoring moving forces on bridges, which has a wide range of applications in the future.

Thinning and dynamics of the glacier terminus at the Pasterze Glacier (Austria), 2016–2021

As a result of global warming, glaciers worldwide recede and lose mass. Glacier ablation is influenced by surface characteristics, in particular the existence of debris cover. The evolution of glaciers may also be influenced by the existence of proglacial lakes, which are worldwide increasing in number and size. We examine the recent changes of the terminus of Pasterze Glacier by discussing the thinning and dynamics of the glacier terminus along with the changes of the glacial-proglacial transition zone between September 2016 and September 2021. By considering land cover in the interpretation, we find that glacier surface characteristics show different rates of elevation changes and surface movement. We mainly use orthophotos and digital elevation models (DEMs) resulting from airborne surveys of 12 different acquisition dates, but also draw on ablation stake measurements, lake water level data, water temperature data, as well as thermal infrared (TIR) imagery. While debris-covered ice lowered typically −5.0 m a−1 ± 4.6 m a−1 (mean ± standard deviation), debris-free ice was affected by ablation in the range of −7.0 m a−1 ± 2.7 m a−1, thus demonstrating that melt rates in similar elevations are related to surface characteristics. The elevation change rates were, in most cases, in a similar range throughout the observed periods of time. The horizontal displacement close to glacier-marginal crevasses amounted to up to ∼8 m a−1, but was mostly in the range of ∼1–4 m a−1. Considering both horizontal displacement and elevation changes, we find that clean and dirty ice surfaces show larger thickness losses and are moving faster compared to debris-covered glacier surfaces. Diurnal and seasonal fluctuations of lake water levels in the range of decimeters and lake water temperatures mostly clearly exceeding 0 °C are indicative of the potential influence of the proglacial lake on the glacier terminus. Given the decelerating and decaying behavior of the Pasterze Glacier in recent decades, we interpret the change rates of surface lowering and horizontal displacement 2016–2021 to be influenced by other factors such as the recently formed proglacial lake. This is also supported by direct ablation measurements that mostly show lesser ice melt differences compared to DEM-based surface elevation changes, suggesting that other factors such as thermally-induced melting contributed to an increased elevation difference.

Construction monitoring and analysis of low mountain ridge tunnel

In order to obtain the change rule of surrounding rock structure displacement and supporting structure internal force with time during the construction of the low mountain ridge tunnel, this paper relies on the Xishan Tunnel Project as the background. During tunneling, the displacement around the tunnel, the subsidence of the surface, the internal force of the steel arch and the pressure between the two layers of support are monitored dynamically. According to the above monitoring and measurement data, and the monitoring data analysis and nonlinear regression fitting, the predicted trend curve is obtained, the displacement change rules and characteristics of various surrounding rocks of the tunnel are obtained, to ensure the construction safety and stability requirements of supporting structure, and to provide a reasonable opportunity for the construction of secondary lining.

A numerical study on thickness of rear under-ride protection in case pick-up to semi-trailer full rear impact

In the global supply chain, large trucks, tractors, and semitrailers are essential as the final step in this complex network. However, they have many potential dangers because the gaps from the semi-trailer's floor to the road surface are high, so small cars easily get underride. To solve this issue, some regulations have required the installation of additional protection devices on the front, sides, and rear where these gaps exist, for example, FMVSS 223, 224 of the US, or UNECE R58 of Europe. Using LS-DYNA software and trailer and pick-up models from proven sources to set up a collision simulation, then proceed to change the thickness of the rear underride protection device to assess the effect. The collision was designed with 55.8 km/h of pick-up and a stationary trailer. The effect of change thickness on axial displacement and energy changes is presented. The study results are expected to be helpful for the structural design and safety assessment of various structures including marine vehicles and cars against collisions. Keywords: Rear under-ride, protection device, design, truck, semi-trailer

A behavioral nonlinear modeling implementation for MEMS capacitive microphones

We are highlighting the behavioral nonlinear system-level modeling approach for MEMS capacitive microphones. The combination of finite element modeling and large signal nonlinear circuit modeling provides a strong capability to predict electroacoustical performance for capacitive transductions. Circuit simulation tools such as Cadence Virtuoso have emerged as powerful aids in designing behavioral models in both linear and nonlinear regimes. Typical small signal lumped element models fail to capture the MEMS behavior which changes over pressure and electrical bias conditions. The models described herein capture diaphragm displacement and capacitance change over large pressure ranges for a simply supported circular plate. This can be coupled with the electrostatic force, due to the applied bias voltage, and converted back to pressure, thereby realizing a feedback loop in the circuit model. The nonlinear model capability is extended to predict capacitance-bias behavior and estimate pull-in of the MEMS device. The microphone sensitivity, signal-to-noise ratio, and harmonic distortions are accurately predicted using the nonlinear large signal model when compared to measured microphone data.

Case study on the secondary support time and optimization of combined support for a roadway under high in-situ stress

Roadway support can effectively improve the stability of roadway excavation and ensure the safety of underground mining. This study investigates the secondary support time and parameter optimization of combined support for a deep roadway in the stage of resource replacement in the Huize lead–zinc mine in Yunnan Province, China. The aim of this study is to increase the stability and safety of the roadway and decrease the cost of support. Research on support methods and failure modes has shown that under the action of high in-situ stress in deep mining, the surrounding rock of the roadway exhibits obvious rheological phenomena. The change in the radial displacement of the roadway is combined with creep tests of the main exposed surrounding rock to determine the secondary support time. Numerical simulations and orthogonal tests are utilized to optimize the support parameters in terms of the roof subsidence, floor heave displacement, side displacement, and plastic zone by analyzing the effects of the sprayed concrete thickness, bolt length, bolt row spacing, and bolt diameter on the support results. The proposed secondary support time and combined parameters can provide a reference for roadway support in similar strata.

High-Sensitivity Seawater Refraction Index Optical Measurement Sensor Based on a Position-Sensitive Detector.

The refractive index of seawater is one of the essential parameters in ocean observation, so it is necessary to achieve high-precision seawater refractive index measurements. In this paper, we propose a method for measuring the refractive index of seawater, based on a position-sensitive detector (PSD). A theoretical model was established to depict the correlation between laser spot displacement and refractive index change, utilizing a combination of a position-sensitive detector and laser beam deflection principles. Based on this optical measurement method, a seawater refractive index measurement system was established. To effectively enhance the sensitivity of refractive index detection, a focusing lens was incorporated into the optical path of the measuring system, and simulations were conducted to investigate the impact of focal length on refractive index sensitivity. The calibration experiment of the measuring system was performed based on the relationship between the refractive index of seawater and underwater pressure (depth). By measuring laser spot displacement at different depths, changes in displacement, with respect to both refractive index and depth, were determined. The experimental results demonstrate that the system exhibits a sensitivity of 9.93×10-9 RIU (refractive index unit), and the refractive index deviation due to stability is calculated as ±7.54×10-9 RIU. Therefore, the feasibility of this highly sensitive measurement of seawater refractive index is verified. Since the sensitivity of the refractive index measurement of this measurement system is higher than the refractive index change caused by the wake of underwater vehicles, it can also be used in various applications for underwater vehicle wake measurement, as well as seawater refractive index measurement, such as the motion state monitoring of underwater navigation targets such as AUVs and ROVs.

A Simulation of the Mechanical Testing of the Cell Membrane and Cytoskeleton.

Cell models play a crucial role in analyzing the mechanical response of cells and quantifying cellular damage incurred during micromanipulation. While traditional models can capture the overall mechanical behavior of cells, they often lack the ability to discern among distinct cellular components. Consequently, by employing dissipative particle dynamics, this study constructed a triangular network-like representation of the cell membrane along with cross-linked cytoskeletal chains. The mechanical properties of both the membrane and cytoskeleton were then analyzed through a series of simulated mechanical tests, validated against real-world experiments. The investigation utilized particle-tracking rheology to monitor changes in the mean square displacements of membrane particles over time, facilitating the analysis of the membrane's storage and loss moduli. Additionally, the cytoskeletal network's storage and loss moduli were examined via a double-plate oscillatory shear experiment. The simulation results revealed that both the membrane and cytoskeleton exhibit viscoelastic behavior, as evidenced by the power-law dependency of their storage and loss moduli on frequency. Furthermore, indentation and microinjection simulations were conducted to examine the overall mechanical properties of cells. In the indentation experiments, an increase in the shear modulus of the membrane's WLCs correlated with a higher Young's modulus for the entire cell. Regarding the microinjection experiment, augmenting the microinjection speed resulted in reduced deformation of the cell at the point of membrane rupture and a lower percentage of high strain.

A Controlled Variable Study of the Biomechanical Properties of the Proximal Femur before and after Cancellous Bone Removal.

The biomechanical characteristics of proximal femoral trabeculae are closely related to the occurrence and treatment of proximal femoral fractures. Therefore, it is of great significance to study its biomechanical effects of cancellous bone in the proximal femur. This study examines the biomechanical effects of the cancellous bone in the proximal femur using a controlled variable method, which provide a foundation for further research into the mechanical properties of the proximal femur. Seventeen proximal femoral specimens were selected to scan by quantitative computed tomography (QCT), and the gray values of nine regions were measure to evaluated bone mineral density (BMD) using Mimics software. Then, an intact femur was fixed simulating unilateral standing position. Vertical compression experiments were then performed again after removing cancellous bone in the femoral head, femoral neck, and intertrochanteric region, and data were recorded. According to the controlled variable method, the femoral head, femoral neck, and intertrochanteric trabeculae were sequentially removed based on the axial loading of the intact femur, and the displacement and strain changes of the femur samples under axial loading were recorded. Gom software was used to measure and record displacement and strain maps of the femoral surface. There was a statistically significant difference in anteroposterior displacement of cancellous bone destruction in the proximal femur (p < 0.001). Proximal femoral bone mass explained 77.5% of the strength variation, in addition proximal femoral strength was mainly affected by bone mass at the level of the upper outer, lower inner, lower greater trochanter, and lesser trochanter of the femoral head. The normal stress conduction of the proximal femur was destroyed after removing cancellous bone, the stress was concentrated in the femoral head and lateral femoral neck, and the femoral head showed a tendency to subside after destroying cancellous bone. The trabecular removal significantly altered the strain distribution and biomechanical strength of the proximal femur, demonstrating an important role in supporting and transforming bending moment under the vertical load. In addition, the strength of the proximal femur mainly depends on the bone density of the femoral head and intertrochanteric region.

Stability analysis of unsaturated loess slopes subjected to extreme rainfall incorporating creep effects

Rainfall-induced landslides are common natural hazards, particularly in cases involving unsaturated soils. Slope instability issues may arise due to extreme climate events, while, creep effects can also contribute to landslide problems. In this study, a modified ViscoElastic-ViscoPlastic constitutive model is developed to more accurately characterise the mechanical properties of unsaturated loess, considering stress-level dependency of stiffness and creep properties. In addition, to better characterise the collapsibility of loess, the relationship between strengths and matric suction has been introduced. The infiltration process of an unsaturated porous medium is illustrated by the Van Genuchten model and the generalized Darcy’s law. Additionally, the atmospheric boundary condition is incorporated in the numerical simulations, considering factors such as runoff generation and various climate events.In the context of slope stability analysis, a numerical approach has been developed to determine the safety factor of the slopes, by using displacement changes as the key assessment criterion. A good agreement between numerical and analytical results has been observed, verifying the proposed approach to determining safety factor. Finally, in parametric analyses, the effects of creep and matric suction on safety factor have been identified. Slope stability of unsaturated loess slopes subjected to different rainfall intensities and rainfall durations has been studied. The maximum depth of the sliding part increases obviously when considering the contribution of creep deformations, which is crucial in analysing slope stability.

Computation of shear buckling stress of thin-walled sections using constrained spline finite strip method

The direct strength method (DSM) design for shear incorporates the elastic shear buckling stress of the cross-section to evaluate the ultimate shear capacity of thin-walled members. To calculate the shear buckling stress using the finite strip method (FSM), the shape functions for longitudinal interpolation are an issue, while capturing the phase change of displacements along the plate strip. This paper presents a novel constrained spline finite strip method (cSFSM) that eliminates the phase change of displacements. Although constrained buckling analysis for shear stresses is reported in the literature based on FSM, the present study is unique in determining pure buckling stresses for simply supported members subjected to shear edge stress. The formulation also provides an accurate representation of the variation of shear stress along the longitudinal and transverse directions of the plate. Hence, coarse discretization of cross-section is sufficient to obtain the accurate shear buckling stress. The formulation is demonstrated on channel sections with lips subjected to shear edge stresses, and elastic buckling stresses are compared with results available in the literature and also with the finite element method (FEM). Illustrative examples are presented on lipped channel members with different end conditions and longitudinal stiffeners on flanges and webs, to calculate the pure elastic buckling stresses under shear edge stresses. The calculation of buckling stresses for members subjected to longitudinal variation of shear and flexural stresses is also presented to calculate coupled and uncoupled buckling stresses.

Design of high-precision displacement safety monitoring and three-dimensional spatial alarm system for Beidou based on intelligent algorithms

The purpose of this study is to design a system that can monitor the displacement changes of engineering structures in real time and provide timely alarms when abnormal displacement is detected, in order to provide efficient safety monitoring and early warning functions and reduce the safety risks of engineering structures. The study adopted a combination of intelligent algorithms and the Global Satellite Navigation System (Beidou). By installing high-precision displacement sensors, monitor the displacement changes of the engineering structure. Then, intelligent algorithms are used to analyze and process the data collected by the sensors in real time, in order to extract the characteristics of displacement changes. At the same time, combined with the positioning data of the BeiDou navigation system, high-precision displacement monitoring is achieved. When the monitoring results exceed the set threshold, the system will automatically trigger an alarm mechanism to promptly notify relevant personnel for processing. Through experiments and comparative analysis, the Beidou high-precision displacement safety monitoring and 3D spatial alarm system based on intelligent algorithms designed in this study can effectively monitor and alarm displacement changes. The system has the characteristics of high accuracy, real-time performance, and reliability, which can timely detect displacement anomalies and provide reliable safety monitoring and warning functions.

Research on the Factors Influencing the Seismic Performance of Grouting Sleeve Assembled Double-Column Piers

The present study investigated the influence of key design parameters on the seismic performance of prefabricated precast assembled piers’ connection parts to better adapt to the industrialized construction of prefabricated precast assembled pier connected using grouting sleeves. Relying on a prefabricated assembled bridge in the actual project, the ABAQUS software was used to establish a refined solid finite element model of prefabricated assembled piers connected with grouting sleeves. Numerical simulation analysis was conducted for the piers with low circumferential reciprocating loading. The seismic performance of the prefabricated assembled piers was evaluated in terms of hysteresis characteristics, dissipation characteristics, and damage development. The effects of the length of the grouting sleeve and the diameter of the longitudinal reinforcement on the seismic performance were also investigated. The maximum error between the numerical simulation results and the test results was 5.7%, and the plastic region of the precast assembled pier obtained from the numerical simulation was consistent with the test results, indicating that the numerical simulation method is accurate and reliable. When the length of the grouting sleeve increased from 0.6 to 1.2 m, the yield load, peak load, and dissipation of energy of prefabricated assembled piers increased by 11.6%, 10.9%, and 11.4%, respectively; no significant change in residual displacement; ductility coefficient decreased by a small amount. When the longitudinal reinforcement diameter increased from 20 to 50 mm, prefabricated assembled piers yield load, peak load, and dissipation increased by 99.6%, 89.3%, and 218.9%, respectively, whereas the residual displacement increased by 137.3%, and the ductility coefficient decreased more. Increasing the length of the grouting sleeve or increasing the diameter of longitudinal reinforcement improved the stiffness of the piers, causing the piers to displace less and damage less under the same force, but the residual displacement would increase.

Modeling and Optimization of Interior Ballistics within Pneumatic Underwater Launchers

A new area of underwater equipment research focus is the use of underwater unmanned vehicles (UUVs) with launch mechanisms to deploy lightweight and small-sized robots for functions including communication, exploration, and detection. The internal ballistic mathematical model of the underwater launch system for small robots is established in this paper. The internal ballistic parameters and the robot displacement and velocity change rule over time are obtained. The optimization calculation of the crucial parameters to be determined by the particle swarm algorithm is completed. Following optimization, the gas cylinder’s initial pressure is 2 MPa, its capacity is 30 L, its opening area is 9.683 × 10−5 m2, and its opening time is 0.02 s. A numerical simulation is performed for the small robot’s underwater launch process, based on the mathematical and physical model supplied by Fluent 2020 software. The results yield the robot’s motion law and the properties of the flow field during the launch process. The purpose of the underwater launcher experiment is to determine the robot’s motion characteristics. The accuracy of the theoretical model is confirmed by comparing and analyzing the numerical simulation results with the actual data.

Responsiveness to exoskeleton loading during bimanual reaching is associated with corticospinal tract integrity in stroke.

Device-based rehabilitation of upper extremity impairment following stroke often employs one-sized-fits-all approaches that do not account for individual differences in patient characteristics. Determine if corticospinal tract lesion load could explain individual differences in the responsiveness to exoskeleton loading of the arms in chronic stroke participants. Fourteen stroke participants performed a bimanual shared cursor reaching task in virtual reality while exoskeletons decreased the effective weight of the more-impaired arm and increased the effective weight of the less-impaired arm. We calculated the change in relative displacement between the arms (RC) and the change in relative muscle activity (MC) between the arms from the biceps and deltoids. We calculated corticospinal tract lesion load (wCSTLL) in a subset of 10 participants. Exoskeleton loading did not change RC (p = 0.07) or MC (p = 0.47) at the group level, but significant individual differences emerged. Participants with little overlap between the lesion and corticospinal tract responded to loading by decreasing muscle activity in the more-impaired arm relative to the less-impaired arm. The change in deltoid MC was associated with smaller wCSTLL (R2 = 0.43, p = 0.039); there was no such relationship for biceps MC (R2 < 0.001, p = 0.98). Here we provide evidence that corticospinal tract integrity is a critical feature that determines one's ability to respond to upper extremity exoskeleton loading. Our work contributes to the development of personalized device-based interventions that would allow clinicians and researchers to titrate constraint levels during bimanual activities.

Robotic-assisted Total Knee Arthroplasty Technology Provides a Repeatable and Reproducible Method of Assessing Soft Tissue Balance.

Soft-tissue balancing is an important factor in primary total knee arthroplasty (TKA), with 30 to 50% of TKA revisions attributed to technical operative factors including soft-tissue balancing. Robotic-assisted TKA (RATKA) offers opportunities for improved soft-tissue balancing methods. This study aimed to evaluate the repeatability and reproducibility of ligamentous laxity assessments during RATKA using a digital tensioner.Three experienced RATKA surgeons assessed preresection and trialing phases of 12 human cadaveric knees with varying degrees of arthritis. Ligamentous laxity was assessed with manual varus and valgus stresses in extension and flexion, with a digital tensioner providing feedback on the change of laxity displacement. Intraclass correlation coefficient (ICC) analyses were used to determine the repeatability within a single surgeon and reproducibility between the three surgeons.The results showed excellent repeatability and reproducibility in ligamentous laxity assessment during RATKA. Surgeons had excellent repeatability for preresection and trialing assessments, with median ICC values representing excellent reproducibility between surgeons. Surgeons were repeatable within 1 or 1.5 mm for preresection and trialing assessments. On average, the variation within a surgeon was 0.33 ± 0.26 mm during preresection and 0.29 ± 0.28 mm during trialing. When comparing surgeons to each other, they were reproducible within an average of 0.69 ± 0.33 mm for preresection and 0.65 ± 0.31 mm for trialing.This study demonstrated the reliability of robotic-assisted soft-tissue balancing techniques, providing control over ligamentous laxity assessments, and potentially leading to better patient outcomes. The digital tensioner used in this study provided excellent repeatability and reproducibility in ligamentous laxity assessment during RATKA, highlighting the potential benefits of incorporating robotics in TKA procedures.

Higher-order thin layer method as an efficient forward model for calculating dispersion curves of surface and Lamb waves in layered media

The thin layer method (TLM) is an effective semi-discrete numerical tool for analyzing wave motion in stratified media. The TLM can calculate the eigenvalues and eigenvectors for both propagating and decaying waves, which is essential to simulate waves near the source. The eigenvectors are particularly useful in various applications, such as estimating modal contributions, calculating synthetic seismograms, determining Green’s function, analyzing site response, and solving wave amplification problems in earthquake engineering, to name a few. In practice, most engineering applications use linear element-based TLM. However, the overall performance of TLM depends upon the type of element and the number of thin layers. The linear element TLM requires relatively thin sub-layers to obtain an accurate solution, making it computationally expensive and time-consuming. This study explores the potential of using non-linear higher-order TLM (HTLM) for forward modeling. The mathematical framework of TLM is used to formulate the generalized HTLM in determining the multimodal dispersion curve of Rayleigh, Love, and Lamb waves. The convergence and computational efficiency of different orders of HTLM have been investigated on a diverse set of published soil profiles and plate-like structures. Since non-linear interpolation functions better capture the change in displacement and stress between the layers, the findings reveal that the HTLM consistently outperforms the linear element TLM in terms of accuracy. Furthermore, the computational efficiency of different order HTLM is analyzed by comparing the total degrees of freedom and CPU time. Remarkably, higher-order HTLMs exhibit improved accuracy without increasing the computational burden, making them an attractive option for practical applications such as global search-based inversion and full spectrum inversions where fast and economical forward modeling is essential. Therefore, the HTLM will become helpful in seismic wavefield modeling, dynamic soil characterization, non-destructive evaluation methods, wave propagation analysis through waveguides, seismic site response analysis, etc.

Spatiotemporal changes of climatic disasters and population displacements in Africa

ABSTRACT Frequent global climatic disasters are posing a growing threat, especially in populous Africa. Understanding the intrinsic interactions between climatic disaster and the resulting affected population in Africa can provide a representative sample of developing countries for global governance of climate change. This study explored the spatiotemporal dynamics in climatic disasters and disaster-related displacements in Africa from a geographical perspective. The results showed that climatic disasters in Africa occurred with seasonality consistent with African climate characterized by distinct dry and rainy seasons, manifested as flood, storm, and heat wave events occurring in the rainy season, wildfire and cold wave events taking place in the dry season, and prolonged droughts spanning both dry and rainy seasons. Meanwhile, the spatial pattern and variation trend of climatic disasters and displacements varied greatly by the five African sub-regions. East Africa experienced the highest number of disasters and displacements, while Southern Africa bore the least. Flood and drought triggered a third of total displacements in the most populated West Africa. The least frequent disasters dominated by flood only affected less than 10.9% of the total in Central Africa. 6.8% of the total displacements were primarily induced by coastal flood in North Africa.

Numerical simulation study on the embedding depth of anti slip piles in fully weathered granite landslides

Abstract Taking the reinforcement project of the fully weathered granite landslide in Fanling as the research object, this study establishes a numerical slope model with anti-slide pile reinforcement, the most common means in slope reinforcement engineering, while considering the pile-soil interaction. Using the strength reduction method, the effects of different anti-slide pile embedment depth on the stability of the reinforced slope are discussed. The research results indicate the following findings. (1) The embedment depth is negatively correlated with the slope displacement. (2) When the embedment depth is more excellent than 7m, the slope Factor of safety is 2.032&gt;2.0, which meets engineering safety requirements. (3) According to the changes in displacement and the factor of safety, the stress analyses of the pile body and the economic factors, the optimal embedment depth for the Fanling landslide are determined as 8 m. The results afford certain application and promotion values by providing theoretical references and technical guidance for similar anti-slide pile reinforced slope projects.

Numerical Simulation of Double-row Piles in Deep Foundation Pit Excavation

This paper aims to investigate the stress and deformation characteristics of double-row piles in deep foundation pit excavation by selecting representative strata in the Changchun area. The changes in bending moment, displacement, and earth pressure of double-row piles during the excavation are established using the FALC 3D software. The findings indicate that the deformation of the front pile is larger than that of the back pile, and the earth pressure distribution of the fornt pile deviates from the conventional Rankine earth pressure theory. Moreover, there are noticeable variations in earth pressure at the soil layer interface of the rear pile.