Finite Element Numerical Simulation Method Research Articles

The analysis of Yunnan Dayao basin effect based on microtremor test and numerical simulation

AbstractMicrotremor tests and finite element numerical simulations were used to analyze the seismic ground motion effects of the Yunnan Dayao sedimentary basin. The results of the microtremor relative to the reference point spectral ratio (HS/HR) method showed that the spectral ratio curves of each observation point in Dayao basin show multipeak characteristics, indicating that the site consists of different soil layers; the predominant frequencies of each observation point mainly are 6~9 Hz in the basin and there are lots of differences in the predominant frequencies of different observation points, which indicate that the site stiffness of each observation point is different; the differences of spectral ratios between the east–west directions (EW) and the north–south directions (NS) reveal the site's anisotropy. The amplification coefficient characteristics of each observation point in the basin obtained by numerical simulation show that the predominant frequency is 6 ~ 9 Hz; the amplification coefficients of each observation point are different; the edge effect and the focusing effect amplify the seismic ground motion in the basin; the different amplification coefficients of the two sub‐basins reflect the significant effect of the basin soil layers' differences on the seismic ground motion, the site is softer and amplification coefficients are larger; the slope degree of basin edges significantly affects the seismic ground motion near the basins edge, the amplification coefficients of the slope steeper and amplification coefficients larger. This study demonstrates that the microtremor test spectral ratio (HS/HR) method has good reliability applied to the analysis of basin effect and combining the finite element numerical simulation method is more effective in revealing the basin effect mechanism.

3D Cementitious composites printing with pretreated recycled crumb rubber: mechanical and acoustic insulation properties

ABSTRACT Cementitious materials incorporating recycled crumb rubber have become a common sustainable resolution in diverse building environments to achieve various functions in terms of lightweight, ductility, as well as energy absorption. This study explored the 3D printed rubberised cementitious composites (3DPRC) in two aspects: examining the effects of crumb rubber pretreatment conditions on compressive properties; conducting experimental and numerical analysis on the acoustic dissipation characteristics of 3DPRC. Fine crumb rubber granules (3-5 mm) replaced 10%, 20%, and 30% of river sand in the composites. Uniaxial compression tests indicated that the compressive strength of 3DPRC decreased with the increase of crumb rubber content and introduced anisotropic behaviour. Impedance tube tests were conducted to evaluate the sound absorption and insulation capabilities of 3DPRC. An optimal Noise Reduction Coefficient (NRC) of 0.35 was achieved with 30% crumb rubber. The sound insulation properties depend strongly on the mass density and porosity of the 3DPRC. Additionally, it is proved that the volume of built-in air gap has positive effects on both sound absorption and insulation properties. The results from Finite Element Method (FEM) numerical simulations correlated well with experimental data, proving the efficiency of the simulation and validating the experimental results.

Mechanical response and failure mechanism of circular inclusion embedded in brittle materials under dynamic impact

Inclusions are prevalent in both natural and synthetic materials. Gaining a comprehensive understanding of their dynamic response and interaction with the surrounding matrix is essential in fundamental mechanics and engineering applications. This study aims to achieve such understanding through theoretical analysis, experimental investigations, and numerical simulations, focusing on the dynamic destruction of inclusions and the underlying mechanisms. Firstly, the circumferential, radial, and shear stresses around elastic heterogeneous inclusions were derived by the wave function expansion and Duhamel integration methods. Subsequently, a set of experiments on sandstone specimens containing three types of inclusions (plaster, epoxy resin, cement) were conducted utilizing the Split Hopkinson Pressure Bar (SHPB) system in conjunction with high-speed photography and Digital Image Correlation (DIC) techniques to obtain the surface deformation of inclusion specimens. Eventually, a series of Finite Element Method (FEM) numerical simulations adopted suitable materials were also carried out to investigate the fracture process of inclusion and matrix under dynamic impact. The results demonstrate that the stress distributions and fracture mode of matrix and inclusion are highly dependent on the physical and mechanical properties of the inclusions and the surrounding matrix, specifically, density ρ, elastic modulus E, Poisson's ratio v, and strength. With an increase in the E and v, there is a reduction in the concentration of circumferential stress, while the radial and shear stresses experience an increase. The experimental and numerical results corroborated the theoretical findings and indicated that the localized dynamic stress concentrations induced by wave scattering around the inclusions directly dominated both local and overall specimen failure. Due to the dissimilarities in elastic parameters and strength between the inclusion and the matrix, the stress state of the inclusion and the interface is not homogeneous. Under dynamic loading, the weaker inclusion experiences tensile cracking at both ends of the loading, and as the mechanical properties (ρ, E, v, and strength) of the inclusion rise, a transition from tensile- hybrid-shear failure occurs within the inclusion. The findings of this study help us understand the dynamic failure mechanisms of dissimilar inclusions in brittle material.

Evaluation of acoustic environmental effects and improvement method of ecological fish-nest bricks in the Yangtze River Basin: A model-based case study

With the rapid development of the Yangtze River Basin, the issue of underwater noise pollution has become increasingly severe, which has adversely affected aquatic creatures, particularly fish. Ecological fish-nest bricks (EFNBs), a new type of eco-friendly revetment, can provide a favorable habitat for fish. However, its effects on the acoustic environment remain unclear. The finite element numerical simulation method of acoustic-structure coupling is adopted to explore the acoustic environment of EFNBs, analyzing the impact of sound source frequency (within 300 Hz), structural forms, and arrangement of these bricks on the internal sound pressure level. The sound pressure level distribution of A-EFNBs were also analyzed at a distance of 0–0.5 m from the opening. A method of acoustic environment improvement is proposed, which utilizes porous polyurethane sponge (PPS) sound-absorbing material to establish a conducive acoustic environment for fish in EFNBs. The study results indicate that at low frequencies of sound source (f ≤ 150 Hz), the sound pressure level within EFNBs slightly decreases compared to the adjacent areas without EFNBs. The sound pressure level variation within the bricks increases with sound source frequency. The peak sound pressure increases with the number of openings. Interval arrangements can in general decrease sound pressure by less than 20 dB. At higher frequencies(f＞200 Hz), the sound pressure level at the opening of the A-EFNBs tends to increase. However, the PPS sound-absorbing material substantially reduces the sound pressure level by 15 –55 dB, rendering it an effective method for improving the acoustic environment for fish. The PPS sound-absorbing material is more suitable for habitat improvement of black carp (Mylopharyngodon piceus) and grass carp (Ctenopharyngodon idellus) with relatively low hearing thresholds among the four famous Chinese carps. The research findings can serve as a reference for designing and implementing river ecological restoration projects.

Enhanced fluorescence emission of a single quantum dot in a porous silicon photonic crystal—plasmonic hybrid resonator

Abstract Currently, much interest is attracted to investigating the potential of hybrid systems that exhibit plasmon-induced photoluminescence (PL) enhancement of quantum emitters in terms of optoelectronics and biosensing applications. The implementation of these systems based on photonic microcavities offers benefits due to a stronger localization of the field within the resonant cavity. Porous silicon is one of interesting materials for engineering such microcavities thanks to the simplicity of its fabrication and the possibility to embed emitters from the solution into a ready-made resonator. In this theoretical study, the fluorescence enhancement of a quantum dot (QD) in a hybrid system based on a porous silicon microcavity (pSiMC) and silver nanoplatelets (AgNPs) was investigated using finite element method (FEM) numerical simulations. For this purpose, infinite arrays were simulated by using a periodic unit cell. The pSiMC was designed as two λ/4 distributed Bragg reflectors with alternating refractive indices and a cavity layer of a double thickness between them. For comparison, simulations were also performed for an AgNP and a QD in a reference monolayer with a constant refractive index without a microcavity structure. The results show QD fluorescence enhancement in the AgNP/pSiMC hybrid system, mainly due to the higher excitation rate.

Mechanism analysis of the abnormal head-cover vibration of an ultra-high-head pump-turbine operating in pump mode by CFD and FEM

ABSTRACT Hydraulic excitation causes abnormal head-cover vibration in some pump-turbines, particularly as design heads continue to rise. Pump-turbines with heads exceeding 600 m have reported such vibrations in pump mode, and it is urgent to reveal the reasons. A study was conducted on a head-cover of a pump-turbine with a maximum head of 660 m by 3D computational fluid dynamics (CFD) and finite element method (FEM) numerical simulations to investigate the hydraulic excitation source and vibration mechanism. Results show that the intensive vibration is related to the coincidence of frequency and mode between abnormal pressure pulsations with frequency 6–8f n and the low-order wet mode of the head-cover. A new flow pattern termed the rolling vortex was discovered in the vaneless space under high-head pumping conditions. The 6–8f n pressure pulsations result from the interaction between rolling vortices and guide-vanes, similar to the rotor-stator interaction. The flow mechanism of the rolling vortices is that the outflow velocity near the hub at the runner outlet is higher than that near the shroud, due to the positive blade lean angle and the X-shape distorted blades. Suppressing rolling vortices may help eliminate the abnormal head-cover vibration, which will be attempted in further study.

A standard calibration method based on a symmetric resistance network matrix for galvanic logging instruments.

An increasing number of measurement electrodes have been designed to satisfy the demand for high-resolution detection using galvanic logging technology in complex formations. The forward modeling response analysis of logging tools has important guiding significance in the design of galvanic logging tools. Based on a three-dimensional finite element numerical simulation method, we established a forward model of galvanic multi-electrodes in a complex formation. We also designed a symmetrical resistance network model of the formation with equivalent resistance between two electrodes. A symmetrical resistance network was derived using the balanced bridge method. The asymmetrical admittance matrix was extended to a symmetrical extended admittance matrix to realize a convenient calculation of the equivalent symmetrical resistance network in complex formations. Verification of the microcolumn-focused logging tool, with nine electrodes in a simulated standard well, and an evaluation of the degree of invasion in an actual oil well indicate that this calibration method can improve the measurement accuracy of galvanic logging instruments.

Paleotectonic Stress and Present Geostress Fields and Their Implications for Coalbed Methane Exploitation: A Case Study from Dahebian Block, Liupanshui Coalfield, Guizhou, China

The macroscopic structural fractures (joints) and geostress distribution characteristics of coal reservoirs are important factors affecting the exploitation of coalbed methane (CBM). In this study, the joints in the sedimentary strata of the Dahebian block in Liupanshui area, Guizhou Province were investigated. Directional coal samples were collected for observation and statistical analysis of coal microfractures, the paleotectonic stress fields of the study area were reconstructed, and the tectonic evolution was elucidated. The geostress distribution characteristics of the target coal seam (coal seam No. 11, P3l) in the study area were analyzed using the finite element numerical simulation method. The results indicate that the structural evolution of the Dahebian syncline in the study area can be divided into two stages. The Late Jurassic–Early Cretaceous stage (Early Yanshanian) is the first stage. Affected by the sinistral strike slip of the Weining–Ziyun–Luodian (WZL) fault zone, the derived stress field in the study area exhibits maximum principal stress (σ1) in the NEE–SWW direction. The Late Cretaceous stage (Late Yanshanian) is the second stage. Affected by the dextral strike slip of the WZL fault zone, the derived stress field exhibits σ1 in the NNW–SSE direction. The folds and faults formed in the first stage were modified by the structural deformation in the second stage. The dominant strikes of joints in the sedimentary strata are found to be in the NW–NNW (300°–360°) and NE (30°–60°) directions, with dip angles mostly ranging from 60° to 90°. The dominant strikes of coal microfractures are in the NW (285°–304°) and NE (43°–53°) directions. The distribution of geostress in the study area is characterized by high levels of geostress in the syncline center, decreasing towards the surrounding periphery. The overall trend of the geostress contour line is similar to the shape of the syncline and is influenced by folds and faults. The σ1 of coal seam No. 11 is vertical stress. The prediction results show that the joint density of coal seam No. 11 in the block is 36–50 joints/m, and the shape of the joint density contour line is also affected by the axial direction of the Dahebian syncline and the surrounding faults. The variation in coal seam joint density and the control effect of geostress on joints opening or closing affects the permeability of coal reservoirs. The study results provide significant guidance for the exploitation of CBM.

Numerical Simulation of Impact Effect on Stability of Transmission Tower Foundation

The impact effect can cause structural damage to a transmission tower’s foundation and affect its overall stability. In order to study the influence of the impact effect on the stability of transmission tower foundations, a three-dimensional finite element numerical simulation method was used to investigate the variations in the extent of damage, displacement, and inclination degree of a transmission tower foundation under different impact velocities, impact durations, impactor shapes, and impact locations. The results show that as the impact velocity increases, the damage value of the transmission tower foundation continuously increases, and the damaged area expands. The lateral displacement value increases continuously with the duration of the impact effect, and the variation in lateral displacement follows a linear function distribution. The inclination degree of the transmission tower foundation increases continuously with increased impact duration and can lead to overturning failure. A smaller impact contact area results in a larger compressive damage value for the transmission tower foundation, and different impact contact areas lead to different modes of failure for the transmission tower foundation. The damage value and damaged area of the transmission tower foundation vary with the location of the impact. By comparing the deformation of the transmission tower foundation before and after reinforcement, it is evident that the reinforcement design can significantly improve the deformation resistance and anti-overturning capacity of the transmission tower foundation.

Numerical simulation of attenuation performance of the gas attenuator using argon as working medium of SHINE

The performance of the gas attenuator (GAT) with argon as the working medium for the high repetition frequency free electron laser facility (SHINE) is simulated and investigated by means of the finite element numerical simulation method, and the results of the temperature and normalized density distribution of the gas inside the active gas cell at steady state are obtained, demonstrating the density depression effect of the internal gas and the corresponding attenuation results. Under the assumption of equivalent continuous-wave (CW) power input, the gas pressures are obtained for photon intensity attenuation of 103 at different photon energy (0.4–7 keV) and repetition frequencies (1 kHz, 10 kHz, 100 kHz), and compared with the theoretical calculations. The results show that the density depression is gradually enhanced with the increase in the repetition frequency, and the nonlinear deviation of the simulation attenuation gas pressure relative to the theoretical value is also gradually increased. The thermal outflux on the wall of the active gas cell gradually decreases along the beam path, so the cooling system needs extra attention to the inlet region of the cell. According to the simulation results, at the highest operating repetition frequency of 100 kHz, the attenuation gas pressure varies from 0.0767 to 17 Torr, and the highest wall thermal outflux value reaches 52.1 W/m2. The study provides a useful reference for the performance prediction and subsequent optimization design of the gas attenuator.

SHPB experiments and FDM-DEM coupled simulations on calcareous sand under uniaxial to triaxial deformation

The impact behavior of sand is paramount to geotechnical and protective engineering. Although the one-dimensional impact responses of sand are extensively studied, the behavior of shear under impact loading remains poorly understood as the shear stresses in uniaxially compressed sand cannot attain the failure state. This paper reports the macroscopic responses of crushable calcareous sand under uniaxial to triaxial deformation by split Hopkinson pressure bar (SHPB) experiments. In addition, the mesoscopic mechanism is analyzed by coupled finite difference method (FDM) and discrete element method (DEM) numerical simulations. With an increasing lateral confined stiffness, the p-q curves exhibit a clockwise rotation, signifying a deviation of the stress path from the critical state line (CSL) during the transition from triaxial to uniaxial deformation, meanwhile the Mohr circle experiences a shift from intersecting to tangential contact with the failure line, indicating that shear failure occurs under triaxial deformation. The stress-strain relationships for both compression and shear exhibit four distinct regimes, the initial elastic stage mainly overcomes intergranular friction through particle rotation; the yield stage mainly compresses the skeleton by contribution of displacement; the hardening stage experiences critical particle breakage and then promotes particle displacement and rotation; and the unloading stage with strain softening caused by the asynchrony between impact loading and deformation. Both compressed and shear yield stress increases with an increasing confined stiffness, but the shear friction angle decreases. This indicates that the governing factor in triaxial compression under impact loading is the stress state rather than kinetic friction. Particle breakage in triaxial compression state tends to approach the splitting mode, while in uniaxial squeezing state it tends to approach the Mixed mode.

Study on the Mechanical Response of a Dense Pipeline Adjacent to the Shallow Tunnel

This paper aims to address the issue of disturbance caused by excavation tunnel construction on nearby dense pipelines. Relying on the actual project of Nanchang Metro, the three-dimensional finite element numerical simulation method is used to establish a multi-condition numerical model. At the same time, key influencing factors such as the clear distance, intersection angle, surrounding rock parameter, and construction method are considered. The mechanical response of the dense pipeline adjacent to the dug tunnel was systematically studied, and the influence of key factors on the mechanical behavior of the pipeline was analyzed. The results show that when using the CRD method for construction and grouting reinforcement of the surrounding strata of the tunnel, the maximum settlement of the vault is located at the vault of the right guide tunnel, and the maximum settlement value is located at the bottom of the rainwater pipe directly above the tunnel. The vertical displacement, maximum principal stress, and minimum principal stress of the pipeline are arranged in descending order for the full-face, stepped method, and CRD method. The greater the disturbance to the soil caused by the construction method, the more unfavorable the effect on the pipeline.

Hybrid approach for graphene modeling in numerical simulations of graphene based plasmonic devices with COMSOL

We present a hybrid approach for graphene modeling in the finite element method numerical simulations of graphene based plasmonic devices with COMSOL. The surface conductivity approach for modeling graphene or other two-dimensional materials needs less number of meshing elements if compared to the volumetric permittivity approach; however, it is less intuitive and less compatible with the boundary mode analysis, which provides a very efficient way for the excitation of boundary ports. We adopt the surface conductivity approach in the scattering domain and the volumetric permittivity approach in the boundary ports. A triangular connector with a spatially varying permittivity is introduced to achieve reflection-less coupling between the surface conductivity and the volumetric permittivity. The hybrid model enables the numerical simulation of graphene based devices with COMSOL to be benefited from less storage and calculation time, keeping compatibility with the boundary mode analysis.

Method using singular value decomposition and whale optimization algorithm to quantitatively detect multiple damages in turbine blades

Renewable energy has increased in recent years with a consequential increase in equipment maintenance. Maintenance costs can be reduced by structural health monitoring techniques especially for wind turbine (WT) blade damages. However, the majority are not suitable for on-line measurements and quantitative detections. A quantitative damage detection method is developed to identify multiple damages in a WT blade under in-service operation conditions. Firstly, singular value decomposition is applied to reveal singular information in the operating deflection shape (ODS), which can be treated as damage locations. Secondly, whale optimization algorithm is utilized for a damage severity decision about the natural frequency database between damage severities and natural frequencies, which are constructed by finite element method (FEM) simulations on the detected damage locations in the WT blade. The procedure is applied to FEM numerical simulations of a single WT blade with two and three damages. By adding a certain noise to the simulation dataset, the robustness of the present method is validated. Furthermore, the laser scanning vibrometer is employed to test the ODS as well as natural frequencies of WT blades to testify the performance of the multiple damage detection method. Results show that the present method is effective for the detection of multi-damage in WT blades with a certain noise robustness.

Material's Strength Analysis of the Coupling Node of Axle of the Truck Trailer.

Road transport plays an important role in the transport of goods and people and is important for the national economy. Damage usually excludes the means of transport from operation, which causes disruption of supply chains. One such damage is the failure of the suspension system of the vehicle or trailer, which usually occurs when the vehicle is heavily loaded. Such a defective system has been analyzed in this publication. Mathematical apparatus and finite element method (FEM) numerical simulations were used. A dangerous axle cross-section in terms of load was indicated and the maximum stresses in this area were calculated for two types of roads. On highways, the stress at the critical point was 199 MPa, and on uneven roads it increased to 304 MPa, which is comparable to the yield point. It was found that the second form of vibration may cause stresses in the damage area, but the excitation frequency would have to be quite high. The probability of such a load and failure event occurring is low under operating conditions.

Numerical simulation of the palaeotectonic stress field and prediction of the natural fracture distribution in shale gas reservoirs: A case study in the Longmaxi Formation of the Luzhou area, southern Sichuan Basin, China

Natural fractures have an important relationship with shale gas production. This study selected the reservoir of the Wufeng‐Longmaxi Formation in Luzhou in southern Sichuan as an example. Based on the seismic reflection map of the formation, using the mechanical parameters obtained from the core sample experiment and using the finite element numerical simulation method, a three‐dimensional geological model is established, the tectonic stress field is inverted and the fracture distribution is predicted according to the Mohr‐Coulomb fracture criterion of the rock fracture, which provides theoretical support for the subsequent well pattern layout and is conducive to improving the efficiency of shale gas exploration and development. The analysis shows that the study area is dominated by NE reverse faults, with an inclination of more than 40°. The core observation results show that the filling degree of fractures is relatively high, and the width is mostly less than 1 mm, mainly caused by tectonic shear fractures. The tectonic stress in the sedimentary belt where the syncline structure is deeply buried is higher, the stress in the northwest and southeast tectonic ridges is relatively low, and the differential stress in the northeast tectonic ridge and near the fault is high. The NE fault and the surrounding rock mass have the highest fracture degree; the fracture proximity coefficient is >1.5 and the fractures are the most developed. The degree of fracture development in the area with a gentle structure is relatively low, but it is far from large faults, which is conducive to preserving shale gas.

Force Analysis of Circular Diaphragm Wall Based on Circular Cylindrical Shell Theory

In order to make up for the shortcomings of existing theory calculation methods for circular diaphragm walls, an alternative calculation method was developed with a clear concept based on the circular cylindrical shell theory and superposition principle in elasticity and named the circular cylindrical shell theory calculation method (CCSTCM). We took the north anchorage circular foundation pit of G3 Tongling Yangtze River Highway and Railway Bridge as an example and calculated and analyzed it by the proposed CCSTCM, finite element numerical simulation method (FENSM) and site monitoring. As a result, we obtained the radial displacement, circumferential stress and vertical bending moment of the circular diaphragm wall, and then summarized their regularities. By researching the results of the CCSTCM (TCR), the results of the FENSM (NSR) and the results of the site monitoring (SMR), the following conclusions could be drawn: the numerical calculation model established was reasonable; the variation trends of the data curves of the TCR were highly similar to those of the NSR and SMR; and the TCR were slightly larger than the NSR but slightly smaller than the SMR, and closer to the SMR in general. Finally, the proposed CCSTCM was proven to be correct and applicable and could be used in similar circular diaphragm wall projects.

Study on the ground impact vibration intensity model of high energy warhead explosion

Introduction: In the warhead explosion process, the ground impact vibration intensity will directly affect the target buildings and instruments safety, and it is also of great significance to accurately evaluate the ammunition explosion damage power.Methods: In this study, the finite element numerical simulation method was used to analyze the explosion shock wave pressure and ground shock vibration velocity of TNT explosive with a mass of 100 kg∼1000 kg, and the ground transmission medium of sandy soil, C35 and C140 concrete, and the shock wave pressure and ground shock vibration velocity propagation and distribution law was clarified. Based on the explosion similarity law and dimensional analysis method, a ground impact vibration velocity theoretical calculation model with clear physical significance is established by introducing the property ground propagation medium parameters, taking into account the factors affecting the ground impact vibration velocity.Results: The model calculation accuracy is verified by the measured data. The verification results show that the model calculation accuracy is higher than 91.8%, which improves the calculation accuracy of the explosion site ground impact vibration velocity.Discussion: This research provides more accurate and scientific theory and data support for the ammunition explosion damage power evaluation, and provides a reference for the shock and vibration resistance performance design of instruments, equipment and buildings. It has strong engineering application value.

Study on the Influence of Earthquakes with Different Frequency Content on the Peak Liquid Sloshing Wave Height of Liquid Storage Tank

Liquid storage tank is an irreplaceable and extremely important vessel structure used to store liquid medium. In earthquake disaster, the liquid storage tank will not only be seriously damaged directly, but also cause serious secondary disasters, such as fire, explosion, poisoning, nuclear radiation, etc. The peak liquid sloshing wave height is an important reference index to judge whether the seismic design of the liquid storage tank is reasonable or not. The ratio of peak ground acceleration to peak ground velocity of the earthquake records (shown by A/V ratio) can well represent the characteristics of frequency content of earthquake records. In this paper, the finite element numerical simulation method is used to analyze the seismic response of six rectangular concrete tanks with different liquid heights, and their respective peak liquid sloshing wave heights are calculated. Nine seismic records with different A/V ratios are used, which are low frequency category, medium frequency category and high frequency category and there are three records in each category. At the same time, the equation in Eurocode 8 is used to calculate the peak liquid sloshing wave height of each tank for comparative study. The study results show that the peak liquid sloshing wave height calculated by the Eurocode 8 is greater than that calculated by the finite element method under low frequency and medium frequency earthquake records, indicating that Eurocode 8 is conducive to the preliminary design of the seismic performance of the liquid storage tank. However, in the case of high frequency earthquake records, the calculation result of the finite element method is larger than that of the equation in Eurocode 8. The peak liquid sloshing wave height of the liquid storage tank is more sensitive to the earthquakes with high frequency content, and the Eurocode 8 underestimates the impact of high frequency seismic response on the liquid storage tank.

Numerical Study on the Coupling Effect on a Retaining Structure of a Complex Deep Foundation Pit Group Excavation in a Soft-Soil Area

Based on the complex deep foundation pit group process of the Huimin Avenue Comprehensive Reconstruction Project in Nanjing, the finite element numerical simulation method is used to analyze the deformation characteristics of the retaining structure and the coupling effect between foundation pits during the whole process of excavation and support construction of the complex foundation pit group. Meanwhile, the differences in the deformation characteristics and coupling effects of the retaining structure under different construction time sequence schemes of the foundation pit group are studied. Finally, some suggestions are put forward for the monitoring and construction in this project, which provides a reference case for the design and construction of similar foundation pit groups.