Applied Mechanics and Materials Vols. 353-356

Abstract: To investigate the geotechnical engineering properties of polluted soil, ten soil samples are collected from Anqing copper ore, Anhui Province, China. The geotechnical engineering parameters of the polluted soil are measured in the soil mechanics laboratory. Tests results show that the natural density varies from 1.56 to 2.04t/m³, the moisture content varies from 15.36% to 27.87%, the modulus of the compression varies from 1.27 to 8.10MPa, the cohesion force varies from 32 to 210kPa, and the internal friction angle varies from 25.4 to 57.9 degree. Finally, the properties of the shear strength and the compression are studied, and find that the compressibility of the polluted soil is very big, and the relationship between shear strength and the normal pressure conforms to the law of Coulomb.

Abstract: The coupling analysis has been the focus of study in the practical engineering; its assumed that the material is porous medium in the classical seepage mechanics, processing seepage problems as a single field without considering the coupling factor. The fluid-solid coupling analysis, in short, is the interrelationship between the seepage field and the stress field. Based on the basic theory of coupling model analysis and the establishment of coupling model in the finite element calculation software ABAQUS, this paper analyses the interrelationship between the seepage field and the stress field under the rainfall condition, and proves the two field coupling analysis is more suitable to the actual situation than just considering one single field. It states the microscopic mechanism of the internal coupling field of a slope under the condition of rainfall, and the interaction between the void ratio and the matrix suction.

Abstract: In this paper, the failure mechanism of rock-like specimens with built-in 3D double cracks under fissure water pressure was numerically investigated. The initiation and propagation process of secondary cracks under fissure water pressure was simulated by using the modified elasto-brittle model and the superfine meshing method in the FLAC3D program. The fluid-solid coupling in cracked rock masses was preliminarily studied. Some of the simulation results are in good agreement with the previous results tested by scholars.

Abstract: This paper principally studies the prediction of slope deformation based on Support Vector Machine (SVM). To explore the prediction process, phase space is reconstructed. The geological body’s displacement data obtained from chaotic time series are used as SVM’s training samples. Slope displacement caused by multivariable coupling is predicted by means of single variable. Results show that this model is of high fitting accuracy and generalization, and provides reference for deformation prediction in slope engineering.

Abstract: There are many factors which can affect the mechanical properties of interface .Targeted research about effect anti-slide pile design parameters act on the contact stress is carried out in this paper. Based on the specific slope example and the principle of orthogonal experiment, the effect that the pile spacing (s), pile cross section width (b), pile cross section length/ width (h/b), the pile length (L) conduct on the maximum shear stress between the landslide and anti-slide pile is thoroughly discussed by combining with orthogonal design method and numerical simulation organically. The results show that (1) The order of influence factors respectively is L, S, b, h / b for the maximum shear stress on interface in the front of pile, and it is L, b, S, h / b for the maximum shear stress on behind of pile;(2) L is the main factor that affects the maximum shear stress on the interface between anti-slide pile and soil;(3) Effect about S and L acting on maximum shear stress of the interface respectively is significant and very significant; h/b has no significant effect on maximum shear stress of the interface.

Abstract: This paper study a discontinuum model on the rock mass, which represented by an assembly of jointed elements and a fracture is initiated when the stress in the joint between two elements exceeds a critical value. The rock fracture mechanics model in this paper show that the continuum damage mechanics is based on the fact that the brittle rock has pre-existing defects, and the material failure is a process of growth and nucleation of these defects.

Abstract: The landslide at the tunnel portal in Nanjing Road is mainly determined by a weak intercalated layer between the completely weathered bedrock and the strongly weathered bedrock. The weak intercalated layer has low permeability and weak shear strength, and its interface dip outside of the slope. As the consequence, landslide is likely to happen again due to a rainstorm or other inducement. In order to prevent a second landslide, a comprehensive treatment scheme is presented, which implements anti-slide piles as the major treatment and several auxiliary treatments including filling and compacting the cracks, cutting-off and draining water, locally bolt-shotcrete support, and repairing the existing retaining wall and the lattic frame beams. After applying this scheme, the slope stability meets the design requirements.

Abstract: Based on an Engineering Example which was supported by the stepped soil-nail wall, a numerical analysis model was established by FLAC3D,and the process of the excavation and supporting was simulated, and the numerical results of the soil nails internal force and foundation pit deformation were obtained. The simulated result was consistent with the measured results. It shows that the method of FLAC3D numerical analysis can be used to the numerical analysis of foundation pit excavation and supporting, and it will provide the basis for the design and construction of practice project.

Abstract: This paper takes Nanhu project of Tangshan City under the soil condition of foundation pit excavation as an example. A model is established to research on the mechanical behavior effect of around composite foundation of CFG under soil lateral displacement by using ANSYS finite element software. The model analyzes the distribution law of horizontal displacement, stress of pile, soil between piles of CFG composite foundation under soil lateral displacement. Put forward a calculation formula of pile displacement by considering excavation depth, excavation distance.

Abstract: Based on the rollingcompaction (RC) test of the Nuozhadu coarse rockfill zone of upstream anddownstream I district rockfill engineering, numericalsimulation was conducted to study the particle breakage of RC test usingdiscrete element method (DEM). The movement and the crushing mechanism of theparticles in the RC process were analyzed according to the numerical results ofDEM. The numerical results indicated that the dominant damage were tensionfailure. The crushing zone was approximate inclined 45 degrees to horizondirection and extended to the bottom in the RC process.