The problem of random wave traveling along stratified media is important for earthquake engineering. The rock strata are considered as multi-layered and located above the base-rock, whose material property is assumed to be much stiffer than the above strata; and the power spectrum density of the random excitation is given at the base-rock. The rock strata can be arbitrarily anisotropic for each layer. The governing differential equations are derived in frequency and wave-number domain and only a set of ordinary differential equations should be solved. The precise integration algorithm is applied to solve the ordinary differential equations. Thereafter, the recently developed pseudo-excitation method for structural random vibration is transplanted to the solution of the layered rock responses. Numerical results are given and compared with some classical results. And that show the reasonability of the presented method.

Based on a generalized strength criterion, a new method is presented to evaluate the ability of anti–frost-heave ability via the replacement of ground soil. Compared with the conventional methods, the criterion proposed is more reasonable since more factors are taken into account. The frost-heave force is considered as a kind of external load, and the defects of frozen soil are treated as cracks. The toughness of frozen soil, as an important factor, is introduced in the new criterion. A numerical example of a retaining wall is given to analyze the stability and strength before and after replacement.

Prestressed cable has been widely used in geotechnical engineering；and much attention has been paid to its reinforcing and failure mechanism. Failure mechanism of prestressed cable varies with its type and structure. One of the failure mechanisms is discussed in this paper. It is thought that separated mortar blocks surrounded by steel wire fail in shear one by one. Based on limit equilibrium method，stability judgement of blocks and recursion formula for the transmission of anchoring force after block failure one by one are obtained. The results obtained are of some significance to design and mechanism study of prestressed cable.

The effects of some factors, such as impact loading magnitudes, confining pressure and the types of soils on reconsolidation deformation are studied under impact loading. Particularly, the reconsolidation deformation characteristics of a kind of sand-clay mixture sample are discussed according to laboratory test results; and are compared with the saturated soft clay samples. Besides, the disturbance consolidation, the limit pore water pressure, the effect of test conditions on test results, etc. are also discussed. Based on the test results, the problems of secondary consolidation deformation under various drainage conditions are analyzed. These studies have a great significance to dynamic consolidation method for the reinforcement of saturated soft clay foundation.

According to the characteristics of Iai’s multiple mechanism plasticity model and boundary surface plasticity model, a multiple mechanism boundary surface plasticity model of saturated sand is established. The concept of multiple mechanism is used as a vehicle for decomposing the complex mechanism into a set of simple shear mechanisms defined in one dimensional space. Each virtual simple shear mechanism is simulated by boundary surface plasticity model in the virtual stress and strain space, with which the complexity of getting the scale parameters when each virtual simple shear mechanism is simulated by the modified Masing’s rule in Iai’s multiple mechanism model is avoided. According to a lot of test data, a relation between the liquefaction front parameter and normalized shear work is presented. The effective stress path is well modeled by several parameters. The effect of rotation of principal stress axial directions and large shear displacement of sand in the earthquake induced liquefaction are taken into account at the same time in the model. The computed results are consistent with the laboratory results.

A new method to calculate penetration resistance of pressed-in piles, namely spherical cavity expansion-sliding friction model, is presented. The tip resistance and the side sliding friction resistance of pile are calculated respectively. A computer program, which can plot the calculating curves, is worked out. The calculating result shows that there is a good agreement between the calculated curves and the measured ones.

The results of a pilot study investigating correlations between index tests and soil design parameters are presented for offshore clays are presented. An important objective of the study is to develop a database consisting of high quality laboratory data from tests conducted in a consistent manner. The database includes ten sites from locations in the Atlantic Ocean, the North Sea, the Norwegian Sea, the Caspian Sea and two onshore sites. Analysis of the database shows that there exists a better correlation between preconsolidation stress and liquidity index but with considerable scatter as the liquidity index decrease below 0.5. A strong linear relationships between preconsolidation stress and undrained shear strength for triaxial compression, triaxial extension, and direct simple shear test are also found. Recommendations are given for use of these relationships together with the preconsolidation stress-liquidity index correlation for estimation of in situ undrained shear strength.

The analytical solution of 1-D harmonic response in saturated soil, derived in the companion paper[1], is used in the research of individual contributions of two compression waves, wave velocity and the applicable scale of u-p formulation in saturated soil. Mathematical imprecision is override in the research of individual contributions of two compression waves. The influence of each parameter on the velocity of three volumetric waves is studied. The applicable scale of u-p formulation is quantitatively presented by comparison of the results of u-w and u-p formulation.

Infiltration induces the change of pore water pressure in soils, which is one of the most important factors that affect the behavior of unsaturated soils. So, it is of great significance to analyze and simulate the process of unsaturated seepage correctly. By studying on one-dimensional and two-dimensional rain infiltration problems respectively, the movement of wetting front，water table and the change of distribution of pore water pressure are shown. It represents a straighter and more perspicuous view of infiltration.

General regression neural networks(GRNN) are briefly analyzed. The relationship between the parameter spread of GRNN and the parameter r0 of autocovariance function (squared exponential function) is derived, and the method for computation of autocovariance distance and fitting of autocovariance function is presented based on GRNN. The study indicates that with optimum spread, GRNN can reflect the variability of soil property and the characteristics of spatial autocovariance.

The control method of secant rigidity of pile is put forward in order to determine effective length of pile based on the definition of effective length of foundation pile brought forward. It is applied to determine effective length of a common pile in deep overlay soil layers with linearly elastoplastic load transfer function. Influential factors of effective length such as coefficient of rigidity of pile, pile’s diameter, top settlement of pile, side ultimate displacement, elastic modulus ratio of the bottom soil and surrounding soil and Poisson’s ratio, are thoroughly analyzed. The results show that the factors have certain effects on effective length of the common pile except elastic modulus ratio of the bottom soil and surrounding soil, and Poisson’s ratio. In order to apply to practical project, it is studied how to confirm parameters in the project.

Dynamic equations for seismic response analysis of foundation-structure system are derived from Lagrange equation. The analyses of complex seismic process and nonlinear dynamic characteristics, such as suddenly jumping and path effect of amplitude response, are made with catastrophe model. Some useful conclusions are drawn; and the analytic results are of good value to parameters design of foundation-structure system.

The theory and method of the plastic limit analysis have been introduced systematically; by using the finite element methods and linear programming, the lower limit method can evaluate the bearing capacity and the safety factor of the rock-soil slope .The example shows the correctness and the high precision of this method; meanwhile, its difficulty has been analyzed.

Aiming at the deep alluvium support of coal shaft, the composite shaft lining of high strength concrete and double steel cylinders is presented. Through model experiments, the characteristics of stress and bearing capacity of the composite shaft lining of high strength concrete and double steel cylinders are obtained. In the end, an equation for calculating the ultimate bearing capacity is given based on the theoretical research and experimental results. Thus, the studied results may provide a design basis for engineering practice of this kind of shaft lining structure. The studied results have been successfully applied in four shafts.

A new optical image measurement method of soil and rock microstructure is presented. the soil sample can be measured by general triaxial experiment and optical image measurement at the same time. This method can obtain clear image array of soil microstructure of the same soil sample under different loads; it can be used both in quantitative analysis of soil microstructure change and in measurement of soil micro-displacement field under different loads.

An approach, which is based on the double porosity concept and takes into account pore deformation, has been presented to derive a set of coupled differential equation governing behaviour of porous fissured media. The finite element technique and code has been employed as the numerical methods for the solution of these equations by using of Galerkin finite element methods. Relations relating to rock classification rating RQD and RMR are developed to define changes in effective porosity and permeability that result from the redistribution of strains in disturbed rock mass. At last, an applied example is presented; the results are compared with ones of previous works.

Safety and stability are very important in designing and constructing complex ventilator chamber for its complex construction, large cross-section and little distance between chambers. It is necessary to adopt an effective and accurate numerical method and a calculation model to analyze underground tunnels. The advanced FLAC-3D method which based on 3-D explicit finite difference method, is adopted to calculate the ventilator chambers of a very long highway tunnel. The result indicates that the FLAC-3D method can be used to simulate three-dimensional mechanical behaviors of rock mass.

Some dynamical characters and seismic liquefaction of schistose grain sand are very complex and different to that of the round grain sand; We may reduce the degree of liquefaction if by using the method of code without considering the characters of schistose structure. A new empirical formula of Ncr is suggested to evaluate the seismic liquefaction of subsoil of a metro with considering the schistose structure of Nanjing's sand. According this new method the index of liquefaction of subsoil of a metro section from Xuanwumen station to Nanjing station is middle degree, The distribution of affect-coefficient and index of liquefaction are also described with depth. It is important to take care of the schistose structures to analyze the seismic liquefaction in Nanjing; this result is testified to be correct by dynamical test; the research can improve the accuracy of evaluation.

Based on using linear load transfer function to pile-side soil and pile-end soil, and considering influence of sharing load of the pile-side soil on load transfer law of piles, and using theory of mechanics and approximate solution method—district method of differential equation，a set of approximate analytical formulas of interaction for a flexible single pile with variable cross section and ground soil are derived. For rigid pile cap, situation of flexible pile with variable cross-section are compared with situation of flexible pile with constant cross section by an example; the results show that the bearing capacity of the flexible pile and the composite foundation may be raised by changing pile type. The results of the model test are compared with the results. It is shown that the proposed method has good precision.

According to deformed specificities for rock mass bedding slope, the mode amplitude equation of equilibrium stability built by energy criterion of post-buckling are used, and nearby region at bifurcation point and cracking criterion at bedding slope end are derived. In accordance with mechanism for progressive failure of rock mass bedding slope and characteristic for rheologic deformation, various possible factors affected mode amplitude are analysed; and extremum of mode amplitude of equilibrium stability is given in the form of slope length.

Based on the characteristic of concrete face rockfill dam, a method of computer numerical and figure simulation is given. It is used to simulate three-dimensional nonlinear computation and computer figure simulation in the construction procedure and operation period for the concrete face rockfill dam.

According to the application of root piles to underpinning engineering and the intrinsic character of root piles, a composite constitutive model of root piles and soil is established in reinforcing slope. Some basic characters, such as change of stress and displacement fields, slope stability after reinforcing slopes and safety factor of slopes, are researched. At last, advantages and defects of two constitutive models are compared in evaluating slope stability. The results show that it is possible to adopt composite constitutive model to evaluate reinforcement of slope stability with root piles.

The vibrofloation method without gravel backfill was only thought to be proper for treatment of medium and coarse sand with less than 10 % fine particles. Almost no project case available is concerning vibrofloation without backfill treatment of silty and fine sand. A laboratory test was then carried out to achieve the relating characteristics of the hydraulic silty and fine sand .In this test a reduced scale prototype model was set up, in which pressure gauges were embedded. From the data acquired during and after vibroflotation, the pore water pressure development and dissipation functions are established. The spatial distribution of pore pressure among soil was also studied. The cone penetration test(CPT) was made after each vibroflotation to discover the relationships among CPT, relative density and water pressure. Furthermore, the conclusions obtained from test were then used in guiding a ground improvement project in Shanghai.

Inherent heterogeneous and anisotropic properties of the seepage under karst-engineering geological condition expressed more complexity because of the effect suffered leaching and highly stress field. In this article, K.G.Magomedov’s forecast model has been discussed based on analyzing leaching around the dam site. A disposal way for the permeability in karst pipeline has been given. The penetrating stochastic field around the dam site has been analyzed. A stochastic differential equation has been established for seepage-stress coupling based upon Taylor random FEM. A way has been given for seepage coefficient solution by using the coupling random modeling.

Coupling analysis method of finite element and infinite element is proposed to be used in the structural anti-seismic analysis of metro tunnel on the basis of soil-structure interaction theory. For a better consideration of nonlinear characteristics of soil-structure interaction, Ramberg-Osgood skeleton curve is adopted here to model constitutive relationship of soils, and also GOODMAN element is adopted to model nonlinear working states on the interface between soils and structure. This paper conducts the dynamic analysis and comparison on seismic response of a tunnel structure with double-hole rectangular section and draws some helpful conclusions.

Both the inverse analysis method and the reliability method are combined to analyze slope stability. Based on connections and characteristics of the two methods, a new method is put forward in limit equilibrium analysis of slope to ascertain slope mechanical parameters，which is convenient and applicable. Some concepts such as average point and comprehensive reliability parameter are initially presented. The method gives some clues to process the average values of slope parameters under the condition of limited statistical information.

An experiment of rock fracturing process is conducted under uniaxial compression in order to investigate the behaviors of rock fracturing under chemical erosion. The meso-fracturing process of rock is real-time observed using the microscope and the digital color camera. The effects of rock surfaces and mechanical behaviors are studied under different ionic strengths, values of pH and chemical solutions. The fracturing behaviors of rock under chemical erosion are analyzed. The load-displacement curves, the corresponding micro-images and the schematic diagrams of specimens after failure are obtained.

It is presented that the particle slides and itself is damaged simultaneously when loading，which are described by boundary surface plastic model and elastic damaged model respectively, the influence of particle failure on peak stress ratio is considered. Computation shows acoustic emission rises if the confining pressure and consolidation stress ratio increased, further it is discussed from micro-mechanism.

By a lot of laboratory tests of expansive soil, in the case of expansive soil in Shaoyang city of Hunan province, the engineering deformation characteristics of three kinds of expansive soils have been test studied. The test results indicate: the beginning water content and dried density of expansive soil are the main outside factors that influence the magnitude of their expansibility and swelling quantity; according to the data of expansibility tests and swelling quantity tests, the variational rule of both expansibility fitted curve and swelling quantity fitted curve is the same exponential relation. At the same time, the characteristic curve and the similar relation between the curve of swelling velocity and the curve of shrinkage tests have been studied. Therefore, the study results have provided the important basis for the design of embankment and treatment technique to the existing expansive soil foundation.

The rock mass natural stress of a valley and methods of simulating natural stress field are discussed. The authors recognize that the two factors, regional natural stress condition and the course of valley development, should be considered. The means of combining orthogonal experiment theory with FEM is also discussed through a multi-faceted approach from its feasibility and evaluation angles, and it is applied to computing and evaluating the 3-D natural stress field; of an underground power house of a hydropower station.

Through studying characters of geotechnical engineering of red strata and engineering practices in the red stratum area of Yunnan province, the physico-mechanical characters of the red strata, the distortion-destruction process of slopes of red strata, which are the three stages—the creep, the shearing and the slide, is analyzed. It also analyzes and introduces characters of mechanism of cyclic enlarging of landslide of red strata; and discusses the main hazard of distortion destruction of slopes of red strata, which is the landslide hazard and the hazard of creep, with engineering example. The controlling countermeasures for the hazard of slopes of red strata are suggested accoding to the distortion-destruction characters of slopes, the character and safety of buildings.

The fundamental principle of hydrofracturing method for measuring geostress is reviewed. Several parameters which have important effects on the reliability of results obtained from This method, are briefly investigated. And its prospects of hydraulic fracturing method to estimate the state of geostress in deep-hole stress determination are discussed. The trend of geostress measurement at great depth is pointed out.

An analytical solution to one-dimensional consolidation problem under low-frequency trapezoidal cyclic loading is presented. Based on the solution, the consolidation behavior under the cyclic loading and its influential factors are investigated; and the variation rules of the average consolidation degree and the effective stress with the loading are discussed. Moreover, the principle of variation of the maximum and minimum value of effective stress in soil with the loading is analyzed. It is shown that the development of effective stress is not synchronously with the variation of loading but is in a delayed way.

The vacuum preloading method is used to consolidate the supersoft ground of an expressway. The test indicated that the improvement effect is very obvious. Compared with the conventional preloading method, the project construction time can be decreased by a quarter; the settlement of roadbed reduces 1/3. The strength of soil increases by 1.5 times. The consolidation degree of soil is larger than 95 % after the embankment of height of 6.2 m was filled and vacuum preloading was constructed for 3 months. The displacement of foundation soil is smaller than 0.2 mm/d during the construction period; the embankment and ground soil are stable. The predicted settlement is less than 20 cm. The experience can also be used in similar engineering.

Through in-situ test, the influence of pipe jacking on earth pressure, pore water pressure, groundwater level movement, displacement of earth’s surface and the rule of the degree and area in disturbed soil can be found. The theory explanation is also presented.

The third rubber dam of the Baihe River is directly located on the riverbed. The stratum of dam-base mainly consists of the coarse and gravelly sands. It is also saturated with water and has a strong permeability. Because the dam was ever damaged by water, a new hanged vertical curtain, which was on the verge of a longer impervious blanket concretes, was used to prevent seepage. It is proved that the technique is feasible in the coarse and gravel sands by testing and construction the gunite pile technique. The problems of outflow slurry, emitting slurry and containing sands are also discussed.

Static vertical loading tests and stress tests of four types of piles, that is, the normal cast-in-place pile, the cast-in-place pile with post-grouting, the cast-in-place pile with expanded-base, the cast-in-place pile with expanded-base and post-grouting, are performed in the same site. Based on the field experiments, compares the bearing capacity behavior, the distribution of axial force and lateral friction of the four types of piles. And transmission rule of axial force and the action of lateral friction of the piles is analyzed. The results of researches prove that the cast-in-place piles with expanded-base and post-grouting possess the characteristics of low settlement and high bearing capacity.

Cantilever retaining structure, single-pivot mixed retaining structure, borehole cast-in-place concrete pile multi-arch retaining structure are adopled for a certain deep-foundation pit excavation in Nanjing city. Based on the in-situ measured data in excavation and construction of foundation, the time-space effects of deformations of different retaining structures and outside soil under the same engineering geological and hydrogeological conditions and construction condition are studied.

An economical and reasonable treatment is proposed through analyzing a pile foundation accident. In the treatment the piles in accident are reused and the soft soil around the piles is replaced with sand and gravel mixture. The piles and the sand-gravel cushion are fit together to be a composite foundation with rigid piles, which can improve the bearing capacity of the foundation effectively and decrease the building’s settlement.

A landslide of soil nail wall in old clay is described. According to the failure characters, a back-analysis is done; and the cause responsible for the landslide is analyzed. The analysis and treatment of landslide provide useful data and information for design and construction of soil nail wall in old clay.

Through revealing spacial distribution and physico-mechanical properties of body materials of a tailing dam of a copper mine, and taking advantage of the automatically-search program STED, the integral and local stability of the tailing dam is analyzed; and the results offer a scientific basis and technical guidance for measures dealing with tailing dams.

With the rapid economic development in littoral, for civil projects the people have to encountered many marine oozes foundations, which have higher creep properties. Taking the Guangxi marine ooze for example, the secondary consolidation properties of marine ooze are analyzed based on indoor test data. Finally, some significant conclusions, are obtained so as to guide designing and engineering practice of marine ooze foundations.