Advanced Materials Research Vols. 594-597

Abstract: The behavior of particle migration on soft soil foundation in Pearl River Delta region is analyzed considering the mesoscopic dynamic with vacuum preloading method. The numerical predictions are compared with the fine particle data in terms of settlements, horizontal displacements and vacuum degree of horizontal preloading. The repercussions of including the displacements law of fine particles are also studied. It is found that the analysis considering displacements law results in consolidation by rose diagram of particle migration, which is related to the consolidation of the vacuum preloading of soft soil foundation in Pearl River Delta region. It is apparently inconsistent with the vacuum preloading of the drainage which results from the fine particles migration, but it is fully justified by the fact that the real soil consolidation coordinates corrected for rose diagram obtained.

Abstract: According to basalt areas of the soil slope weathering in Guizhou, design the slope anchor model test in room. Respectively compare the single anchor strain distribution curve, before and after seepage, with different loading time, and magnitude of different strain distribution curve of the same column in the slope, sliding surface and anchor point at the end of a period comparison analysis research. Test shows that, curve distribution along the length of the anchor rod anchor strain is higher in the middle, lower at the ends; anchor deformation mainly on the top of the first row; the slope of feet and peak strain is higher than other parts, and more likely to damage; the early strain will be a negative value, and the bolts are composite components mainly affording hydraulic tensile stress.

Abstract: This Thesis uses the deep clay in the land subsidence area in Xi’an city as the research object, carries out the indoor high-pressure rheological test to the deep clay, discovers the nonlinear model consistent to the rheological property of the deep clay, and conduct a preliminary discussion to model. This thesis has an important preference value and significant meaning to the research of the deformation mechanism of aquitard in this subsidence area Introduction.

Abstract: Zhangjiaba-Enshi 500kV Transmission Line is a backbone network in the West to East Power Transmission Project of China, which passes through the factory area of Chongqing Sanxing Iron Mine Factory. According to solving the additional stress on foundation rock produced by tower load based on the Boussinesq theory and the redistribution of surrounding rock stress resulting from iron mining computed by using the calculation formula for redistribution stress on circular chamber in rock mass, this paper analyzes and demonstrates the impact of Zhangjiaba-Enshi Line N327 tower footing pressure mine on mining within the range of mining scheme, and determines that there is no mutual impact between the Zhangjiaba-Enshi Line N327 tower and exploitation of Sanxing ore horizon.

Abstract: The offshore renewable energy includes offshore wind, wave and tidal current energy. The power generation system of offshore renewable energy uses single form in recent year. It has caused low power efficiency, big power fluctuation and high cost of the foundation structure which will seriously hamper the development of offshore renewable energy. Firstly, a summary about the common form of foundation structure was made. Then basing on the different characteristics of a single energy power generation foundation structure, two different comprehensive power generation foundation types were put forward, and the power generation devices were optimized and reasonably arranged, which are formed a system for comprehensive offshore energy power generation. In addition, the connection, the load and structural features of each comprehensive power generation foundation structure were discussed. The results provide a basis for the design of foundation structure for comprehensive power generation of offshore renewable energy.

Abstract: The principle of effective stress based on unsaturated soil material model and the boundary conditions of rainfall infiltration on the slope are introduced. The numerical model is built according to the example, and then the ABAQUS finite element program, which is combined with fluid-solid coupling, is used to simulate the problem of transient seepage field caused by rainfall infiltration. With the powerful post processing functions ability of ABAQUS program, we can observe the variation law with the time of pore-pressure distribution and displacement field and equivalent plastic strain. Moreover, the effect on the stability of slope under rainfall infiltration is analyzed.

Abstract: Removed at authors request.

Abstract: Core test data from 10 wells indicate that the sandstone reservoir in Yuanshi oilfield is characterized by low permeability, thin pore throat, high clay mineral content, and strong sensitivity, which are likely to cause reservoir damage and affect development result. Based on the characteristics of water-sensitive, velocity-sensitive low permeability reservoir as well as non-Darcy flow behavior, the development strategy of high pressure water injection and cyclic water injection has been formulated with the assistance of engineering measures such as fracturing and reducing well spacing.

Abstract: Cracking development in soils is of significance for their physical and mechanical properties. The fines content in soils is one of the most important factors in cracking development, leading to it being of great importance to quantitatively study how the cracking development is influenced by the fines content. In this paper, experimental simulations on soil surface cracking were first conducted in the lab with soil from Jiangjia Valley. Digital image processing technology was then applied to investigate cracking in soil with different fines content by describing the surface cracks with crack area density Ac (ratio of all cracks’ area to total surface area of the cracked soil) and crack line density Lc (ratio of all cracks’ perimeters to total surface area of the cracked soil). The conclusions are drawn as follows: 1) Surface cracks increase with fines content going up; specifically, when the soil mass with fines content ranging from 20% to 30%, there is a significant increase in cracks; There is no crack developed in the soil with no fines, comparing to the gradual increase in soils with other fines content. 2) With the loss of water content, Ac and Lc will increase until a constant value is reached. However, small cracks will be closed and big ones will evolve into smaller ones if enough water is added. 3) Soil mass with fines content less than 20% is inclined to have small cracks when it is drying and cracks will be closed if enough water is added; on the other hand, soil mass with fines content more than 20% is inclined to have bigger cracks and they will become smaller when submerged into water. 4) After times of wetting and drying cycles, soil mass shrinks and soil dry density increases, which leads to the decrease of Dc and Lc, which suggests soil with larger dry density will probably have fewer cracks.

Abstract: Landslide induced by earthquakes is one of serious seismic secondary disasters. For some large-scale landslide as discussed in the study, both rigid limit equilibrium method and dynamic finite element method are applied to comparatively analyze the stability against sliding under typical working conditions, and to reveal dynamic response characteristics. Results show that rainfall and earthquake have significant influences on the stability of landslide mass, and the safety factors under rainfall and seismic conditions do not satisfy relevant specifications. The similar results are obtained by dynamic finite element method, but the safety factors are larger than that of rigid limit equilibrium method. The landslide belongs to thrust load caused landslide, featuring upper tension damage and lower shear damage. Some measures, such as cutting slope and reducing load, shear tunnel, anchor tunnel, are recommended to reinforce the landslide mass.