A binary-medium model is proposed for over-consolidated clays within the framework of breakage mechanics which has been advanced recently by the first author. In this model the heterogeneity inherent in the soils is taken into account; and a soil is regarded as a composite material consisting of structural lumps and structural bands to resist the external loads commonly. The model has 10 paramenters; and a method of their determination is also proposed. The results obtained from simulating triaxial test show that the model can reflect the mian features of the behavior of London clay.

The testing systems of Rayleigh wave both in steady-state and transient-state and the calculating principle of dispersion curves of phase velocity of Rayleigh wave are simply described first. Then, the theoretic presupposition, on which the dispersion curve from SASW method may be equivalent with the result from steady-state method, is pointed out. An optimized coherence-function method, by which the testing effect of SASW method can be improved by means of testing procedure control, is proposed at last.

For the u-w and u-p formulations of 1-D harmonic response in saturated soil, a fourth order equation can be derived through these second order equations by elimination. General solution can be derived by solving this fourth order equation. For a special boundary value problem, analytical solution, which satisfies the boundary conditions, can be reached by solving the linear equations that include these boundary conditions. This analytical solution can be used in several research aspects of dynamic response in saturated soil.

The surrounding rock mass of an underground powerhouse under the three Gorges right bank is one kind of jointed rock mass cut by discontinuous joint. Several kinds of bolts and tendons are used to reinforce surrounding rock mass for reducing the damage evolution zones of joints and confining deformation of the surrounding rock mass. According to the theory of self-consistence and the energy generated in the process of sub-cracks propogation, 3D elastic-plastic fracture-damage constitutive model and damage evolution equation are derived. Furthermore, a damage cylindrical element model for calculating anchoring effect is developed .Then these models are used to analyze the stability and optimize the support scheme of the right bank underground powerhouse of the Three Gorges Project. Some beneficial conclusion and advice are obtained that can be used to instruct the construetion.

Flow through fissures in rock mass applies simultaneously the normal hydrostatic seepage pressure and the tangent hauling force (the dynamic seepage pressure) on fissure walls. The equations for the hydrostatic seepage pressure and the hauling force and are proposed under three cases of single fissure without fillings, single fissure with fillings and water-filling flow. A computation example is also given to analyze quantitatively the double mechanical effects of fissure flow. It can be shown that both the hydrostatic seepage pressure and the hauling force make the stress components in rock mass bigger, and double mechanical effects of fissure flow should be taken into account in computing the stress in rock mass.

Using Matlab6.1 platform and related visual program language, several promotions are presented to calculate foundation settlements by layerwise summation method. Initial additional stress formula and nonlinear least square method are used to calculate soil’s stress and void ratio, respectively. The settlement calculation depth and each layerwise thickness would not be constrained. Data’s input and output, calculate procedures are operated visually. The foundation settlement can be calculated out not by tables and figures but by visualization. It is shown that these promotions are practical to compute foundation settlement.

Silty orebody is a typical kind of scattered medium,where the excavation and maintenance of tunnel is very difficult.That grasping the deformation laws of the tunnel surrounding rock is the precondition for searching reasonable constructing principle and supporting scheme. The middle section of tunnel in Jinshandian Iron Mine and surrounding rocks (with the silty orebody referred to,only) are taken as research object, comprehensive tunnel monitoring has been designed for the reseach purpose,the observation over comparatively long period has been conducted on the condition of the force-exerted and deformation on the tunnel and the surrounding rocks. The laws of deformation characteristic of the silty orebody as tunnel surrounding rock are obtained analytically.

A revised counter calculation method for determining parameters of strength of landslide slip soils that integrates the counter calculation method with the data of experiment is put forward. First, the different developing stage of landslide and the strength characteristic of different segment slip of landslide are analyzed and studied. Then, on the basis of analyzing the principle of counter calculation method, the suitable situation of counter calculation method is discussed. Finally, a revised calculation method of strength of landslide slip, which is an effective method for obtaining the parameters of strength, is presented.

Temperature effects on mechanical characteristics of clay soils are analyzed. Some problems are studied in detail, including the thermal consolidation problem, the temperature effects on permeability, thermal conductivity and thermal resistivity, thermal volume change of the clay-water system, etc. Particularly, the changes of pore pressure induced by temperature and the mechanisms of reversibility of the thermal volume change on various types of clay soils are analyzed. Besides, the thermal mechanical models for saturated clays are discussed simply.

The present upper-bound method of limit analysis has many self-contradictory conceptions in theory although its results are reasonable. For example, the associated flow rule is often used at present, but it is shown by experiments that it doesn’t adapt to geotechnical materials; the volume deformation which is larger than real deformation is produced in calculating, but it is assumed to be constant in classical analyzing theory; the velocity slip line is the same as the stress characteristic line according to associated flow rule, but an angle between the two lines is adopted in analyzing; the shear stress and normal stress exist simultaneously in every point of slip surface, but the friction work is not reflected in process of limit analysis. The scientific theory of the limit analysis method about the geotechnical materials is given by the generalized plastic mechanics theory, which thrives in China at the present years. The upper-bound method of limit analysis based on the generalized plastic theory is given in the paper, so these self-contradictory conceptions can be avoided completely and the right solutions are gained. To compare with the classical method, it is proved that the results of limit analysis solutions gained by two methods are nearly the same. The classical method can be used as a practical method since it is simple to solve questions. A systematic analysis and comparison of the above two limit analysis methods is given, and the sameness and un-sameness between them are clarified.

Based on the example of Sweden slice method, defined the boundary water pressure utilizing the flow nets property, it is proved that the seepage force is equilibrant with the water weight and the water pressure around the vertical slice, clarified the mistiness knowledge, simplified the calculation methods, deduced the formula of imbalance force method using seepage force, found out the inhesion reason that the imbalance force is large than normal, and analyzed by practical examples.

According to the mining geology term in Yangzhuang Coal Mine, two basic models of the strike and dip is established; and applying the method of numerical simulation, seam floor breakage depth, scope and mining floor stress afresh distributing are simulated and computed in the different face advance distance and different set-up room length. Contrasting the stress test and injection test in spot, two results are basically identical. It is shown that the results are useful for prevention and cure of limestone water of coal mine floor.

The minimum slope stability safety factor occurs at one moment during the process of earthquake, it is unsuitable to evaluate the anti-slide stability of the slope under seismic load using this value. In this paper the minimum mean safety factor is presented as the evaluating index. The 0.65 times of the maximum amplitude of vibration of the safety factor is taken as the mean amplitude of vibration to evaluate the change of the safety factor with the ground motion time history. The anti-slide stability of a rockfill dam is evaluated by using the minimum mean safety factor. The result is compared with the one of the quasi-static method.

According to the minimum potential theory, the expression of spatial deformation for cement mixing piles-ring beam supporting structure is given; and the influence of the factors on spatial deformation is analyzed. The calculation results are also compared with the measured ones.

Fracture initiation and its extention are analysed based on the theory of linear elastic fracture mechanics of rock. The effect of non-penetrated region of fracturing fluid on fracture extention pressure is briefly discussed. The feasibility of interwell communication by concurrent fracturing is explored. Finally,the application prospects of this research are discussed.

Based on actual measured P-S curve, this article fits the curve to subsection linear function, and uses the slope of the function as bedding value. Then it derives the basic academic equation of variable bedding value elastic foundation beam; and changes it to the same equation form as constant bedding value elastic foundation beam. Having done that we can get the common results using the initial parameter method. This method can also be used in the case of variable cross-section beam and heterogeneous foundation.

An experimental research on the mechanical indexes, swelling-shrinkage properties and pore size distributions of intact Guangxi laterite at different stages of dehydration, has been carried out systematically. The results reached are that, Guangxi laterite is a kind of stiff-plastic clay with well-developed fissures, and the mechanical indexes and swelling-shrinkage properties of intact samples are mainly controlled by the matrix suction during the relative high range of moisture content, while by the fissures instead during the relative low range of moisture content; additionally, the moisture content of the turning points are close to the optimum moisture content of heavy-duty compaction tests; the pores of intact Guangxi laterite are mainly small pores with diameters from 0.01 μm to 0.05 μm, during the process of dehydration, the dry density increases, the total pore size volume decreases, and the pores with diameters from 0.01 μm to 0.05 μm and from 0.1 μm to 1.0 μm represent the most obvious decrease in volume.

Freeze dehydration and mercury intrusion porosimetry was used to study the change of pore size distribution of a structured soft soil, during one-dimension compression. It was found that when pressure increased beyond the structure yield stress, the largest pores began to break down. If the pressure was increased continuously, smaller pores would be affected; but the intra-aggregate pores could not be changed during compression. Pore structure breakage potential was defined in terms of the evolution of the pore size distribution in different stress level.

The air permeability of soil generally refers to the rate which water diffuses through the soil and airflows through the soil. Currently, underground railroads, largc-scale underground structures and pipelines in developed countries adopt the shield method. Generally, this method needs air pressure to stabilize the digging. Subsurface, therefore it is critical to control the permeability of the soil. This paper is based on the results of the permeability experiment at Taipei basin. The detailed analysis of the results leads to the derivation of the respective permeability.

For knowing about rock rheological characteristic of north anchor block in Runyang Yangtze River bridge foundation engineering, the uniaxial compression creep testing has been studied by simulating the actual lpading state of the rock using biaxial rock rheological testing equipment (CSS-1950 type). At the same time the generalized Kelvin mode has been selected for fitting analysis, we find out the creep basic law of the rock, and some correlative rheological parameters are also gained, such as viscosity factor, etc.

The test device and method on the water conduction coefficient for large sample under triaxial stress state are introduced. The tested results from the 18 coal seams in China have made known that the water conduction coefficients of the coal masses are attenuating in minus exponential law with the volume stress increasing, and increasing in positive exponential law with pore water pressure increasing. In statistical sense, the water conduction coefficients of the coal masses are interrelated with the coal metamorphic grade. But they are also influenced by the geological and structural conditions of the coal seams. It should be based on the test to evaluate coal seam permeability. The study results are of some guide meaning for coal seam infusion, gas suction and coal gas exploitation.

The main electrical resistivity properties of the cement soil are given by laboratory and field tests. Research shows that the cement soil with higher unconfined compression strength, higher cement content, longer time and lower water content, has higher electrical resistivity. In addition, The orthogonality test results indicate that factors influencing on the electrical resistivity of the cement soil are salt content, cement content, water content, flyash content, lime content in succession. By comparing field electrical resistivity test with standard penetration test, pile boiling observatin, it can be concluded that the electrical resistivity test is available for checking engineering quality of the cement deep mixing pile.

Surfacewave theory was firstly proposed by Rayleigh which can be used in even medium; many other learners developed Rayleigh’s theory and proposed another theory which can be used in layered medium. But all of the methods are based on semi-infinite elastic space; there is a little research in the medium which has the limited dimension in horizontal direction, such as the deep-mixing wall. According to the boundary condition, the deep-mixing wall can be simplified as plane-stress, plane-strain and elastic restriction. Author finds that the Rayleigh wave’s velocities are almost the same in the three conditions as in the semi-infinite elastic space and check out the result by the model-test in laboratory so as to provide the scientific testimony for the Rayleigh wave’s application to limited dimension medium.

Based on the analysis of basic physical concept of vacuum, the up-to-date in-situ measurement techniques and applications were summarized for the vacuum drainage preloading in construction engineering. The laboratory tests and engineering practices demonstrated that the soft clay above groundwater level was still under saturation even with vacuum drainage preloading. Therefore, when vacuum data were measured above groundwater level, the reading of vacuum gauge reflected the water pressure in pore void space, whereas if vacuum pressure measurement was located under groundwater level, the reading of vacuum gauge was meaningless.

Through experimental analysis of improved expansive soil with lime of Jinan, Zibo region, the expansive soil ranks are classified. Meantime, the expansibility of improved expansive soil, the relation between compressive strength and lime dose is pointed out. And the optimal ratio of mixing expansive soil to lime is put forward.

Based on a series of triaxial tests about soft clayey rocks in Guangdong, the deformation properties and the regularity of Duncan model parameters are studied. The model parameters about these rocks are provided for numerical evaluation of geotechnical engineering.

According to the complex geological phenomena in rock and soil medium and the features of strata, a three dimensional strata model is established. The function of 3-dimensional strata information system(3DSIS) in geotechnical engineering is to make these phenomena visualized, to process the data collected from one project using database and analysis. The function and application of 3DSIS are shown. The integrated model of 3DSIS, numerical analysis method and expert system is suggested.

The principle of 3-D elastic-viscoplastic block element method is introduced; and corresponding analysis software is compiled by using, VC++ and AVS; and the man-machine interaction function is realized. This software integrates the preprocessor, stress and strain analysis and post processor into a whole system, and presents a feature of data visualization in scientific computation. Finally, a typical example is provided to approve the validity and the practicability of this software.

Crack propagation is modeled by means of manifold method with first order cover function employed. Quadratic displacement functions are formed on manifold element in this situation. An algorithm to deal with the crack tip’s stopping at any place of an element is presented. Thereby, the length of crack extension in each extension step can be controlled by means of the algorithm, and the shortcoming in crack simulation by manifold method with constant cover function is overcome.

3D elastoplastic FEM and the Partial Coefficient Method have been adopted to analyse the stress and deep anti-sliding stability of non-entirety and entirety polygonal line gravity dam. The results show that the entierly polygonal line gravity dam improved the stress and deformation conditions efficiently, but not always so efficiently in steady conditions. The above conclusion has been illustrated by load sharing between arch and beam. On the basis of these, preferable reinforcement has been put forward.

The Method of genetic-support vector machine was applied to forecast the deformation of slope.It is showen that this method can escape from the blindness which is the common phenomenon in man-made choice of parameters of support vector machine.It enhances the learning efficiency of the support vector machine and the capability of forecasting.Through comparison between the forecasting and monitoring deformations, it can help the engineer to modify the plan and keep the stabilization of slope.The engineering case analysis indicates that there is an extensive prospect for the genetic-support vector machine.

Based on the measured data of Fengman dam deformations for many years, the artificial neural network evolved by a genetic algorithm was adopted for forecasting the dam deformation. The shortcomings of the traditional BP artificial neural network lie in the slowness in the convergence rate and the weakness in the generalization ability. Compared with the popular multi-factor regression model and BP artificial neural network, the forecasting model based on artificial neural network evolved by a genetic algorithm had the characteristics of accurately forecasting and global convergence. The practical application to Fengman concrete dam shows that, compared with a commonly used statistical method, the forecasting method proposed can obviously enhance the forecasting precision of dam deformation.

A approximate method for analyzing rigid foundation-piles-soil nonlinear interaction is presented. Q-s curves from static load tests is applied to nonlinear load-settlement relation of pile or soil itself unit. The nonlinear property and linear elastic interaction between two units can be simultaneously computed by iterative method. The analysis of numerical examples show that the suggested method is simple, convenient and efficient.

The updated Lagrangian method of large deformation for the stability analysis of slopes is introduced; and then the equation of elasto-plastic large deformation FEM for the large deformation of slopes are presented. The strength reduction coefficient before a well-defined equivalent plastic shear strain (EPSS) running through from the bottom to the top of a slope is considered as its safety factor. The safety factors of homogeneous soil slope with different gradients are calculated by elasto-plastic large strain FEM method. The results are well coincident with the results calculated by small strain FEM; The elasto-plastic large strain(EPLS) FEM analytical results show that not only the nonlinearity of soil material but also the geometric nonlinearity in the process of failure stability is considered. So, the calculation results of EPLS is more reasonable. the large deformation method is applied to analysis of BIII2 landslide in the water supply reconstruction project from Dongjiang to Shenzhen. The results show that calculation EPSS is more similar to the actual sliding area given by geotechnical survey. The large deformation method is more suitable for the calculation of soft soil(rock) slopes or the wall of foundation pits.

Discrete element method (DEM) based numerical simulation is conducted for the jointed rock under uniaxial press loading. The simulation results have a good agreement with the theoretical results obtained by analyzing the space parameters of joints, which proved the correctness of DEM numerical simulation. The results of DEM agree well with the one of FEM when joints are crosscut each other. The computation results showed quantitatively the anisotropy and size effect of jointed rock.

The h-version adaptive finite element method for 3-D seepage is presented. The adaptive system includes 4 modules: 3-D mesh generation, finite element analysis for 3-D seepage, mesh error estimation and post-process. The effectiveness of this system is verified by the given example.

Considering two uncertainties, randomness and fuzziness, in slope stability assessment, and taking fuzzy random variables as basic variables, a slope fuzzy random failure function taking and a slope fuzzy random limit state equation is established. A methodology is presented so as to obtain the slope fuzzy reliability and reliability index. An example is given, and the results are compared with the current reliability assessment.

Only the pull of geotextile can be considered by the current analysis method of seawall stability. The influence of the friction between geotextile and soil on the seawall stability is ignored.In this paper, a new method to calculate the practical distribution of the friction and the pull of geotextile based on the elastic membrane theory and the finite difference method is developed.The field observation result is considered simultaneously in this method. Furthermore, the effects of the friction and the pull of geotextile on the seawall stability are discussed.A conclusion that the friction between geotextile and soil contributes more to the seawall stability than the pull of geotextile, is got.

The application of a freezing method to construction of the connected aisle for Nanjing metro project is introduced. During the construction, the temperatures of salty water and frozen soil, the deformation of the ground surface, the expanding and releasing pressures in the soil are surveyed. The laws of the survey results are examined. Finally, based on these studies, some suggestions for guiding the construction about the freezing are proposed. Theresatts can be used for reference by similar projects.

The Longxingzhai Tailing Dam was rebuilt after its landslide. Based on the geological data of the old tailing dam and the physico-mechanical parameters of the maferials of the rebuilt dam-body, the safety analyses of the rebuild dam was made. In light of the different influencing factors, some corresponding treatment methods are put forward.

In light of a typical pile-raft foundation engineering example, the monitoring methods and monitoring results of the pile stress, stress and strain of the main steel of the raft, deformations of the raft, soil pressures under the raft, settlement and incline of the foundation under complex karst geological conditions are synthetically analyzed. A detailed description is presented for the synthetical study on the pile-raft foundation under complex geological conditions.