Mudflows are natural phenomena starting from landslides and presenting high impact when they occur. They generate great catastrophes in their path because most of the time there is no indication prior to the failure that triggers them. Understanding how mud is transported is of great importance in infrastructure projects that coincide with hillside areas due to the high risk of occurrence of this phenomenon by cause of the high slopes, which can involve great risks and produce disasters that involve great costs. This work presents the evaluation of mudflows, from the implementation of a laboratory scale experiment in a consistometer with its calibration and validation from numerical models to estimate rheological parameters of the material. Tests were also carried out in an open channel in the laboratory, based on the data previously obtained considering the behavior of the material as a both Newtonian fluid and non-Newtonian fluid. The experiment considered a channel with dimensions of 3 m long, 0.5 m high and 0.7 m wide with slope control, and a mud composition of silty material with 60% moisture. The tests were conducted with slopes of 5%, 10%, 15% and 20%. The numerical models were carried out in ANSYS FLUENT software. In addition, the calibration data of the numerical model were used for a real case study, simulating the slip flow occurred in Yangbaodi, in the southeast of China, occurred on September 18, 2002. The results of the numerical models were compared with the experimental results and show that these have a great capacity to reproduce what is observed in the laboratory when the material is considered as a non-Newtonian fluid. The model reproduced in an appropriate way the movement of the flow at laboratory scale, and for the aforementioned case study, some differences in the final length of deposition were noticed, achieving interesting results that lead the use of the calibrated model towards the estimation of risks due to the mudflow occurrence.

The faster growth of urban areas, coupled with limited available land, has resulted in the development of densely packed buildings sharing common soil media. This proximity increases soil stress, influencing the deformation characteristics of nearby footings. Hence, there is a need to investigate the effect of structure-soil-structure interaction (SSSI) on the footing settlement. The aim of the study is to investigate the effect of SSSI on the footing settlement of a three-story symmetrical RCC building due to the presence of adjacent building with various height. The vertical and differential settlement of footings obtained from SSSI and soil-structure interaction (SSI) analyses are compared by using the finite element software ANSYS under gravity loading. The findings reveal that SSSI substantially amplifies vertical settlement in footings proximate to adjacent structures compared to SSI analysis, consequently inducing significant changes in differential settlement patterns between footings.

Rapid urbanization and land scarcity lead to the construction of multiple structures in proximity, supported on common soil media. This proximity increases soil stress, influencing the deformation characteristics of nearby footings. Hence, there is a need to investigate the effect of structure-soil-structure interaction (SSSI) on the footing settlement. In the present study, the effect of SSSI on the footing settlement of a three-storey building is investigated due to the presence of similar adjacent buildings arranged in various patterns (single adjacent building, side-by-side, L-shape, and inverted T-shape). The various interaction analyses are performed using finite element software ANSYS under gravity loading. The vertical and differential settlement of footings obtained from soil-structure interaction (SSI) and SSSI analyses are compared to evaluate the effect of SSSI under various adjacent building arrangements. The results indicate that in SSI case, inner footings show greater settlement compared to peripheral footings which causes high value of differential settlement between peripheral footings and those immediately adjacent to them. However, the presence of an adjacent structure in SSSI cases provides higher settlement in adjacent footings, which in turn reduces the differential settlement in these footings. Moreover, the SSSI effect on vertical settlement in SSSI (L-shaped) and SSSI (inverted T-shaped) is found to be more in corner footing located near to the adjacent buildings due to overlapping of soil stresses from two sides. The study quantifies the extent of settlement increase in various SSSI cases compared to SSI case, contributing valuable insights to mitigating potential settlement issues in densely developed areas.

The seismic response of underground liquefied natural gas (LNG) storage tanks has been a significant focus in both academic and engineering circles. This study utilized Ansys (2021R1) to conduct seismic analyses of large-capacity LNG tanks, considering the fluid-structure-soil coupling interaction (FSSI), and it was solved using the Volume of Fluid model (VOF) and Finite Element Method (FEM). The mechanical properties of both the LNG tank structure and soil were simulated using solid elements, and seismic acceleration loads were applied. An analysis of liquefied natural gas was performed using fluid elements within FLUENT. Initially, a modal analysis of the tank was conducted, which revealed lower frequencies for a full-liquid tank (3.193 Hz) compared to an empty tank (3.714 Hz). Subsequently, the seismic responses of both the aboveground and underground LNG tank structures were separately simulated, comparing the acceleration, stress, and displacement of the tank wall structures. The findings indicate that the peak relative displacement of the aboveground empty tank wall is 122 mm, less than that of a full tank (136 mm), while the opposite holds true for underground tanks. The period and wave height of LNG liquid shaking in underground tanks are lower than those in aboveground tanks, which is more conducive to tank safety. The deformation and acceleration of underground tanks are lower than those of aboveground tanks, but the Mises stress is higher. The results indicate that underground LNG tank structures are safer under earthquake conditions.

Offshore wind farms are located in marine environments with complex hydrological, meteorological and submarine geological conditions, which pose difficulties for wind turbine foundation design and construction. Therefore, the study of the key technologies of offshore wind turbine foundation design has important theoretical value and practical significance for the assurance of structural safety, the optimization of structural design and the extension of structural service life. In this paper, a numerical simulation model of three pile foundation is established, and a detailed FEA model of grouted area is calculated and analyzed, and influence of grout on performance under different loading conditions is calculated and analyzed. The results show that it is feasible to use the p-y curve method to describe the pile-soil interaction of the three-pile foundation of the offshore wind turbine, the stress check of the whole foundation structure under ultimate load conditions and normal load conditions meets the requirements of the DNV specification, and the result of the fatigue damage check is that the fatigue strength requirement is met in 26.7 years, which indicates that the three-pile foundation structure of the offshore wind turbine is safe and reliable and can be operated safely.

In order to improve the quality of transplanting devices and solve the problems of the poor effect on soil moisture conservation and more weeds easily growing due to the high mulching-film damage rate with an excessive number of hole openings, we developed a dibble-type transplanting device consisting of a dibble-type transplanting unit, a transplanting disc, and a dibble axis. The ADAMS software Adams2020 (64bit) was used to simulate and analyze the kinematic track of the transplanting device. The results of the analysis show that, when the hole opening of the envelope in the longitudinal dimension was the smallest, the transplanting characteristic coefficient was 1.034, the transplanting angle was 95 degrees, and the transplanting frequency had no influence. With the help of the ANSYS WORKBENCH software Ansys19.2 (64bit), an analysis of the process of the formation of an opening in the mulching film and a mechanical simulation of this process were completed. The results indicate that, when the maximum shear stress of the mulching film was the smallest, the transplanting characteristic coefficient was 1.000, the transplanting frequency was 36 plants center dot min-1, and the transplanting angle was 95 degrees. In addition, the device was tested in a film-breaking experiment on a soil-tank test bench to verify the hole opening in the mulching film. The bench test showed that, when the longitudinal dimension was the smallest, the transplanting characteristic coefficient was 1.034, the transplanting frequency was 36 plants center dot min-1, and the transplanting angle was 95 degrees. When the lateral dimension was the smallest, the transplanting characteristic coefficient was 1.034, the transplanting frequency was 36 plants center dot min-1, and the transplanting angle was 90 degrees. The theoretical analysis, kinematic simulation, and soil-tank test results were consistent, verifying the validity and ensuring the feasibility of the transplanting device. This study provides a reference for the development of transplanting devices.

The current paper investigates wave propagation from time-harmonic embedded point source in a semi-infinite anisotropic medium containing underground structure by applying three different computational techniques. Firstly, direct BEM for 2D elastodynamics is applied using the fundamental solution derived by the Radon transform for general anisotropic continua. The second numerical technique is a computationally efficient two-and-a-half dimensional FEM, used to calculate the 3D wave field in the soil. At the boundaries of the mesh perfectly matched layers are instated to prevent spurious wave reflections. The FEM solutions realized by the built-in options in ANSYS are finally utilized with two types of absorbing boundary conditions. The results obtained by the three adopted modelling techniques are properly compared and respective insights regarding their applications are provided.

为了确保油气管道在冻土区的安全铺设,采用ANSYS有限元分析法以及理论计算的方法,对冻土区的管道破坏特征进行研究,研究了冻土的冷生构造分类、油气管道失效因素以及管—土相互作用、管道周围冻土温度场,油气管道的纵向温度场的分布等。研究得出:随着深度的增加,各点土层的最低温度逐渐变小,最高温度逐渐变大,符合低温变化规律;不同深度处地温随大气变化情况符合正弦周期变化,而且随着深度增加,各曲线振幅随深度增加,出现衰减。模拟可知,最大压应力发生在距离67.5 m(分界面距右2.5 m处)处的管顶;最大拉应力发生在距离61.5 m(分界面距左3.5 m处)处的管顶。对于不同厚度的冻土,应采取相应措施,避免冻胀与融沉现象的发生,从而更好的指导冻土区管道的设计、施工以及维护。

为解决季节性冻土区路基结构因冻解破损而发生的各种病害,利用地源热泵系统改变路基结构温度场。以109国道青海省季节性冻土区路基为研究实例,运用ANSYS模拟分析109国道季节性冻土区原始温度场,并分析了地源热泵路基的工作原理及运行效果;介绍了地源热泵系统形式及设计计算中的有关问题,得出地源热泵路基系统的设计参数;利用ANSYS有限元法对地源热泵路基的水平埋管进行模拟分析,通过对比分析得出路堤中水平埋管宜分2层布置(-1 m处埋置4根,每管间距为2 m;-3.5 m处埋置5根,每管间距为4 m)。在上述设计方案下,该地区在全年最冷时刻路基易发生冻胀区域的地温超过0℃。通过模拟分析得出,地源热泵路基是一种新型路基结构,该系统对于防治季节性冻土路基冻胀病害具有积极作用。

季节性冻土层在冬季冻结后,场地的动力特性和卓越周期发生改变,季节性冻土场地内的埋地输油管道的地震反应也必将受到影响。分别对埋地管道在不同冻胀条件下的地震反应进行了计算分析。结果表明冻胀条件埋地输油管道的地震响应影响较大,不同季节性冻土场地冻胀条件下管道的设计与施工都应该考虑季节性冻土的冻胀条件的影响。