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2004, 23 (04): -0 doi:
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STATE-DEPENDENT STRAIN LOCALIZATION

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2004, 23 (04): -533 doi:
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[PDF 483 KB] (1107)

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A state-dependent sand model is implemented in a fully-coupling finite element program to investigate the strain localization problems in sand under drained plane strain condition. Due to its state-dependent feature，the coupling influence of effective mean normal stress and density of soil sample on the strain localization is studied in details. The numerical predictions show that the orientation of shear band is strongly related to effective mean normal stress and material density. The lower the effective mean normal stress is，the less the void ratio of soil samples is and the larger the inclination angle of shear band is.

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REMOTE-SENSING-ROCK MECHANICS(Ⅳ)——LAWS OF THERMAL INFRARED RADIATION FROM COMPRESSIVELY-SHEARED FRACTURING OF ROCK AND ITS MEANINGS FOR EARTHQUAKE OMENS

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2004, 23 (04): -539 doi:
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[PDF 579 KB] (1094)

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The fracturing of initial rock mass is another mechanism of tectonic earthquake. Taking it for experimental modeling object，five kinds of typical rocks were collected from the capital area of China，Beijing，and thermal infrared (TIR) radiation imaging experiments were conducted in condition of compressively-sheared rock fracturing. It is discovered from the experimental study that：(1) there are two thermal-stress coupling effects，thermoelastic effect and friction-heat effect，in the process of compressively-sheared rock fracturing，and the higher the ratio of compressive stress to shearing stress is，the more obvious the TIR radiation temperature increment is，(2) in condition of dominating compressive strain，there exists abnormal TIR radiation omen of rock fracturing，(3) the TIR omen of rock fracturing is of obvious temporal-spatial features，i.e.，the average TIR radiation temperature of rock surface increases rapidly as the load reaches to about 80% of the compressive-shear strength，and the higher the ratio of the compressive stress to the shearing stress is，the earlier the appearance of the TIR omen is，and the front edge of the abnormal high temperature strip along the shearing face will move forward until fracturing. The results are basically meaningful for the remote sensing and the forecast of some natural and rock engineering disasters，such as earthquake，rock burst，mine burst and landslide.

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DEFORMABLE AND RUPTURABLE BLOCK MODEL FOR 3D
DISTINCT ELEMENT METHOD

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2004, 23 (04): -545 doi:
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[PDF 206 KB] (895)

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The deformable and rupturable block model is given for 3D distinct element method based on the rigid block model(plane to plane contact types). This method can be applied to stability analysis of rock slope，and the joints of rocks and the rupture failures in the rocks are considered. In order to justify this method and its computer program，a sample is given to show the rupture of slopes. The results of computation shows that this method is feasible and reasonable.

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NUMERICAL SIMULATION ON ROCK BREAKING UNDER HIGH PRESSURE WATER JET

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2004, 23 (04): -550 doi:
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[PDF 286 KB] (1120)

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The evolvement of rock damage impacted by high pressure water jet is simulated with nonlinear FEM and dynamic rock damage model. The numerical results show that most of rock damage and breakage take place in several milliseconds，the main damage behavior under a general continual jet is tensile damage caused by the rock unload and the jet impacting，and the evolvement of rock damage shows step changed. The effect of water jet parameters on rock breaking is studied. The numerical results agree well with experimental results，so that the method established in this paper can simulate rock breaking under high pressure water jet and the study results can be used to design and optimize rock breaking under water jet.

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EXTENDED BAYESIAN METHOD OF INVERSE ANALYSIS
IN GEOENGINEERING

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2004, 23 (04): -555 doi:
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[PDF 289 KB] (1112)

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In the light of defect of the conventional Bayes’ method，a new inverse analysis method is discussed by using probability theory，statistical principle and modern information theory. With the matching coefficient b，site information is combined with previous information，so that the least square method，maximum likelihood method and Bayes¢ method are unified in form. In addition，the best order of prediction model can be calculated by the quality and quantity of observed values. With the quantitative analyses on b，the weighted ratio between observed values and initial estimation values is obtained directly for given parameters.

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VISCO-ELASTICAL ANALYSIS ON INTERACTION BETWEEN SUPPOTING STRUCTURE AND SURROUNDING
ROCKS OF CIRCLE TUNNEL

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2004, 23 (04): -561 doi:
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[PDF 158 KB] (945)

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Regarding released load as the function of time，the interaction between supporting structure and surrounding rocks of circle tunnel with time is deduced through analytic method. The study result of this paper is significant for designing permanent of supporting structure to reflect the spacial effect of working face.

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DETECTION OF 3D ROCK BLOCK CONTACTS BY
PENETRATION EDGES

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2004, 23 (04): -565 doi:
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[PDF 216 KB] (1029)

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Detection of contacts between 3D blocks is a key problem in 3D DDA(discontinuous deformation analysis)and DEM (discrete element method) analysis. In this paper，the limitations of the approaches commonly used to detect 3D block contacts are discussed. A new approach called penetration edges method is put forward for the detection of contacts in 3D blocks system，and the contacts between two 3D blocks are classified into seven types. The principle of this new approach is robust and can overcome the limitations of the commonly used methods. This new method can greatly reduce the amount of calculation and is easy to be coded for analysis.

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FUZZY MATHEMATICS MODELS ON ROCKMASS DISPLACEMENTS DUE TO OPEN-UNDERGROUND COMBINED MINING FOR THICK ORE BODY WITH STEEP DIP ANGLE

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2004, 23 (04): -572 doi:
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[PDF 221 KB] (1207)

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The mathematical models on rockmass displacements for underground mining and slope stability are established by using fuzzy mathematics theory and applied to predict the rockmass displacements and deformations due to open-underground combined mining for the thick ore body with steep dip angle. The fuzzy mathematics method is used to determine the engineering parameters for analysis and calculation. The results of calculation can be applied to predict ground surface movements due to underground mining，and provide a theoretical basis for mining engineering design.

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FORECASTING MODEL OF CAVING SPACE FOR UNDERGROUND ENGINEERING IN JOINTED ROCKMASSES

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2004, 23 (04): -578 doi:
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[PDF 242 KB] (698)

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According to the fundamental condition to form a falling block in underground engineering，the interset relationship of structural plane traces and excavation traces is analysed. Then a possibility space of falling blocks is found. Using the random distribution character of structural plane in rockmass，the forecasting formula of falling space possibility is obtained. By analyzing engineering cases，the possibility of falling height and falling volume，and the curved surface of falling space possibility are given，which changes with the variation of the interval distance of structural planes.

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ARTIFICIAL NEURAL NETWORK PREDICTION MODEL OF MINING-INDUCED DAMAGE OF BUILDINGS

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2004, 23 (04): -583 doi:
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[PDF 234 KB] (1018)

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The main factors affecting the mining-induced damage degree of buildings are comprehensively analyzed. Then the model is established to predict the damage degree of buildings by applying the theory of artificial neural network(ANN). Based on a large amount of cases related to buildings damaged by mining，the predicted results of the model and the measured values are compared and analyzed. The results show that it is feasible to predict the mining-induced damage degree of buildings by ANN technology.

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INSTABILITY CRITERION OF FAULT ROCKBURST BASED ON GRADIENT-DEPENDENT PLASTICITY

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2004, 23 (04): -588 doi:
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[PDF 155 KB] (1425)

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Analytical solution of instability criterion for fault rockburst is proposed using shear strain gradient plasticity theory and energy criterion. Fault band is treated as one dimensional shear problem and the thickness of the band is dependent on characteristic length of rock. Dissipated potential energy and post-peak stiffness of fault band are deduced and both of them are concerned with the thickness of fault band. To propose an instability criterion，half of fault band and half of elastic rock outside the band comprise a system to which energy criterion is applied. The criterion shows that stability of the system depends on the constitutive parameters and structural size. So，the criterion exhibits size effect. Present instability criterion for fault rockburst is analogous to coal pillar rockburst criterion，for lower ratio of shear elastic modulus to shear softening modulus and lower ratio of thickness of fault band to size of elastic rock outside fault band lead to instability of the system. The advantages of present investigation for fault rockburst based on gradient-dependent plasticity are that thickness of fault band，dissipated potential energy，post-peak stiffness and instability criterion can be analytically presented，and plastic shear strain is localized into fault band，which is consistent with field observations.

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INFLUENCES OF NONLINEAR FAILURE CRITERION ON STABILITY ANALYSIS OF VERTICAL CUT USING NONLINEAR SQP ALGORITHM

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2004, 23 (04): -592 doi:
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[PDF 168 KB] (1091)

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A new technique is described for computing rigorous upper bound on stability factors of vertical cut under the condition of plane strain. A perfectly plastic soil model is assumed. The failure of soil is governed by nonlinear yield criterion. Sequential quadratic programming(SQP) is used in conjunction with the limit analysis of classical plasticity theory. A new kinematically admissible velocity field is constructed. When using linear failure criterion that exceeds the actual nonlinear failure criterion，the stability factor formulation of the upper bound theorem leads to a classical nonlinear programming problem，where the objective function，which is to be minimized，corresponds to the dissipated power. The upper bound optimization problem may be solved efficiently by applying a nonlinear SQP algorithm，and stability factors are obtained，which agree well with previous achievements.

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3D GEOLOGICAL MODELING AND ITS APPLICATION
TO SLOPE ENGINEERING

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2004, 23 (04): -597 doi:
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[PDF 340 KB] (2215)

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Three-dimensional geological modeling is important for engineering decision，geological analyses and prediction，and improvement of cartographical efficiency. Through an engineering example，the process of establishing a three-dimensional geological model，including data analysis and pretreatment，surface and solid creation，the disposal of the fault，stratum and other factor concerned with the three-dimensional geological modeling，is elaborated. A three-dimensional model suited for engineering project is produced by using GemCom software platform and is examined at last. In addition，the method of adopting Laplace interpolation integrated with the irregular triangle net (TIN) to create a three-dimensional surface，which has much more progress compared with the traditional irregular triangle net，is put forward.

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STUDY ON DETERMINATION OF STABLE SLOPE CONFIGURATION FOR OVAL-SHAPED FURROW PITS

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2004, 23 (04): -603 doi:
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[PDF 242 KB] (968)

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Taking the oval-shaped rock circle which is on the slope of an oval-shaped furrow pit as an example and supposing that the stress in circle direction of the rock circle is equal at every point，the stable slope configuration is derived for the oval-shaped furrow pit under the conditions，that is，the rock mass is continuous，homogeneous and elastic，it is only loaded by its dead weight is excavated as an oval-shaped trumpet. A great quantity of stripped waste rock can be reduced by the slope configuration determined by the proposed model，as compared with that determined with the traditional theory of slope stability.

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STUDY ON HYDRODYNAMICS MECHANISM OF LARGE HIGHSPEED
LANDSLIDE IN THE SET-OUT STAGE

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2004, 23 (04): -607 doi:
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[PDF 344 KB] (1486)

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During the process of large highspeed landslide in the set-out range，due to the lock segment suddenly snipped，shearing stress is released and thus pore water pressure is suddenly increased，which may produce a very high increase in temperature，convert the water in sliding zone into vapor and create steam pressure. The coupling of pore water pressure and steam pressure results in effective normal pressure reducing significantly under the sliding surface. This is the main reason for the sliding mass to acquire a high velocity in the set-out range. On the basis of triaxial experiment，the relation is discussed between pore water pressure and rates of shearing，and the formula is deduced of pore water pressure in the set-out stage of large highspeed landslide. The characteristics of temperature field of sliding surface is studied in the set-out stage. The depth of heat conduction by highspeed friction is calculated. Furthermore，the vaporization is analyzed of pore water in the sliding zone，and the value of steam pressure is calculated.

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CALCULATION METHOD OF STABILITY FOR UNSTABLE ROCK AND APPLICATION TO THE THREE GORGES RESERVOIR

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2004, 23 (04): -614 doi:
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[PDF 199 KB] (1391)

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As one of typical two geologic disasters in the Three Gorges Reservoir，unstable rock is the result from disorder interaction of multi-factors such as geologic strata，geomorphologic characteristics，fissure water pressure and earthquake，etc. On the basis of failure mode，the unstable rock is divided into three models，i. e. unstable sliding rock，unstable fall rock and unstable topple rock. The main loads to cause unstable rock failing in the reservoir are weight of unstable rock，fissure water pressure in nature，fissure water pressure in strong precipitation and earthquake force. There are three types of load combination. The first one is weight and fissure water pressure in nature，the second one is weight and fissure water pressure in strong precipitation，and the third one is the first type of load plus earthquake force. According to both unstable rock model and load combination the stability calculation method is developed through limit equilibrium theoty and rock mass structure theory. These proposal methods have been extensively applied to the stability analyses and control of unstable rock in the Three Gorges Reservoir.

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THEORETIC AND EXPERIMENTAL STUDIES ON SEEPAGE LAW OF SINGLE FRACTURE UNDER 3D STRESSES

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2004, 23 (04): -620 doi:
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[PDF 167 KB] (1081)

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A thorough study is carried out to answer whether the permeability coefficient of the fracture in rock is influenced by lateral stresses. The physical model and strict relative equations of rock mass with single fracture under 3D stresses are proposed by considering the tectonic characteristics of fracture in rock. In the model，it is supposed that the fracture in rock is composed of two body matrixes and the fracture is filled by soft material，whoes elastic modulus is much less than that of the body matrixes. Under 3D stresses，the coupling deformation of fillings and body matrixes makes the fillings dense and the permeability coefficient of the fracture decreased，in which the lateral deformation of the fracture plays significant role. The lateral deformation of body matrixes is equal to that of the fillings in fracture when the fracture is very narrow. Meanwhile the density of the fillings in the fracture will be changed with the lateral deformation and consequently the permeability coefficient of the fracture will be changed. The deduced calculation formula of permeability coefficient is examined by large amount of triaxial experimental data of coal and limestone. The simplified calculation formula of permeability coefficient with only normal stress is the same as traditional one. It is concluded that the lateral deformations caused by lateral stresses make important effects on the fracture seepage，whose relation is of the form of negative exponent law.

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PARAMETER IDENTIFICATION OF 3D GROUNDWATER FLOW
MODEL WITH IMPROVED GENETIC ALGORITHM

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2004, 23 (04): -625 doi:
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[PDF 213 KB] (991)

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Based on simple genetic algorithm(SGA)，an improved genetic algorithm (IGA) is put forward. The decimal system is used to overcome the shortage of binary system in function optimization problems. The operating method of younger generation chromosome prepotency(YGCP) is put forward. The best chromosome clone(BCC) operation and multi-generations adjusting environment(MGAE) operation are used. The algorithm is of several main functions，such as expediting constringency，avoiding earliness，and improving precision，when it is used in parameter identification of groundwater flow model. 3D unsteady state flows in inhomogeneous，isotropic confined aquifer are taken as an ideal model，and the application process of the algorithm is discussed to inverse problem of hydrogeology parameters with finite element method. It is shown from calculation results that the presented algorithm is very effective，and is of vast application vista for groundwater seepage flow and groundwater resource evaluation.

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APPLICATION OF PP METHOD BASED ON RAGA TO ASSESSMENT OF SAND LIQUEFACTION POTENTIAL

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2004, 23 (04): -631 doi:
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[PDF 182 KB] (1007)

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The assessment model of sand liquefaction potential is investigated using projection pursuit (PP) method with real-coding-based accelerating genetic algorithm (RAGA). The algorithm and the flowchart are proposed. The practical example shows that the PP method is feasible and effective to assess sand liquefaction potential，and the result is good. The model provides a possibility for visual evaluation on sand liquefaction potential.

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ANISOTROPIC DAMAGE MODEL AND ITS APPLICATION TO ROCK MATERIALS UNDER IMPACT LOAD

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2004, 23 (04): -635 doi:
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[PDF 324 KB] (1088)

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An anisotropic damage model is established to describe the damage evolution characteristics of remaining rock masses in geotechnical engineering. A second-order tensor is chosen as the damage variable. Then the expression of damage-dependent elasticity tensor is deduced and the constitutive equations of damaged rock are built by using an equivalent state. The damage threshold is regularized in order to reflect strain-rate sensitivity of rock materials under impact load. The results of research indicate that damage model can simulate damage characteristics of rock materials under impact load and provide theoretical evidences for stability analysis of rock that has been disturbed by impact load in geotechnical engineering.

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INFLUENCE OF CONFINING PRESSURE ON PARTICLE BREAKAGE AND SHEAR EXPANSION OF CALCAREOUS SAND

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2004, 23 (04): -641 doi:
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[PDF 223 KB] (1258)

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Particle breakage at low stress level leads to a special stress-strain relation for calcareous sand. By assuming that the strengths of particles follow a certain probability，damage parameter is obtained，then a damage bounding surface model is constructed. The relationship among particle breakage，shear expansion and confining pressure are discussed，and theory and experiment results are of good agreement.

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MODEL FOR PREDICTING SHEAR STRENGTH OF SATURATED SOFT CLAY AFTER IMPACT LOADING

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2004, 23 (04): -645 doi:
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[PDF 334 KB] (1314)

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Previous studies showed that the samples of saturated soft clay undergoing several stages of impact loading and reconsolidation show obvious quasi-overconsolidation state，and have an increased shear strength. In this paper，the definition of quasi-overconsolidation ratio is given，and furthermore a model for predicting the shear strength of saturated soft clay after impact loading is suggested. In this model，the conditions of partial drainage and stages of impact are taken into account. The calculation results by the proposed model are in good accordance with test data. Besides，the effect of disturbance consolidation on the undrained shear strength by this model is discussed.

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STUDY OF BASIC PARAMETERS ON LOCAL GROOVING TOP-CAVING WITH CONTROLLED EXPLOSION

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2004, 23 (04): -650 doi:
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[PDF 308 KB] (1016)

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A new united method，local grooving top-caving，is proposed by controlled explosion in disposing abandoned stope. The characteristics of the methods，location，width and depth of grooving，and thickness of loose rock cushion are studied，and the calculated grooving location is validated by two-dimensional finite element analysis，meanwhile the effective cutting roof is evaluated by acoustic emission technique and photography at Dongtongyu Gold Mine. The study results show that the new method is fulfilled at Dongtongyu Gold Mine. The calculation of width and depth of grooving obtained by theory are dependable，and the calculated grooving location is basically reasonable for the continuous and regular abandoned stope. However，for the complicated abandoned stope，the theoretical location is deviates from actual case and two-dimensional finite element calculation should be taken to correct the result. Application of the united methods can not only subtract continuous area of mining abandoned stope，and separate it with mining system on deep level，but also eliminate the hidden danger of large scale roof sudden falling，and make roof stress redistributed to keep safe production.

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SEISMIC STABILITY ANALYSIS OF SLOPE AT NORTH BANK OF FENGJIE CHANGJIANG RIVER BRIDGE

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2004, 23 (04): -657 doi:
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[PDF 242 KB] (1144)

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The statically stable slope would not be stable when earthquake happens. When earthquake happens，the potential sliding body suffers some dynamic load，in addition to the pore water pressure arising and the anti-sliding force on potential sliding surface decreases due to the anti-shear strength of rock and soil body decreasing. Therefore，it is not sufficient only to make static calculation for important slope. In the present paper，as an instance，the seismic stability of the slope at the north bank of Fengjie Changjiang river bridge is studied by transfer-coefficient method，based on the detail exploration and the seismic hazard analysis for the engineering site.

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STUDY ON THE LAW OF PARTICLE ACCELERATION MOTION AND ITS APPLICATION TO PREVENTION OF SANDSTORM

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2004, 23 (04): -663 doi:
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[PDF 202 KB] (930)

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The law of particle acceleration motion in gas-solid two-phase flow is studied. The analytical solution and the numerical one of the acceleration time and the acceleration length are given for particles under the action of Klyachko and Putnam forces. The acceleration time and the acceleration length are studied for the single spherical particle with different diameters and velocities of wind，and the results are applied to the acceleration motion of the dust and sand particles. In the end of this paper，it is presented that the key to prevent sandstorm is to prevent the particle from wind erosion and acceleration，and some suggestions on prevention of sandstorm are made by analysis and comparison.

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STRUCTURE AND APPLICATION OF STRONG SHELL-BODY SUPPORT IN SOFT ROCK ROADWAY

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2004, 23 (04): -668 doi:
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[PDF 325 KB] (950)

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Connotation and three kinds of basic support form of strong shell-body support in soft rock roadway is put forward in this paper. The support principle is analyzed by dynamics method，on the basis of which，calculation formula of reasonable bolt length，interval and diameter of bolt and its impact on support structure is educed. The result indicates that effect of “short，thin and dense” bolt support precedes that of general bolt. The presented study result is approved in soft rock roadway support practice in Longkou mine bureau.

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PARTIAL FACTORS OF PREFABRICATED PILE DESIGN BY CPT

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2004, 23 (04): -673 doi:
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[PDF 171 KB] (956)

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Taking account of Shanghai Foundation Design Standard，the statistic criteria of Ps，fi and Psb for prefabricated pile are explored with the random field and the reliability theory，and the theoretical formulas to obtain the statistic characteristics of design parameters are put forward. For the convenience to employ the theoretical formulas in practice，a new analysis approach is derived on the basis of the correlation distance，pile dimensions and the calculating range of Psb and fP. The ultimate bearing capacity of prefabricated pile is estimated by CPT method at nineteen sites in Shanghai，and the statistic properties of the reliability index are obtained according to the numerical simulation results. Based on the results of reliability indexes and their statistic properties，the partial factors for defining the bearing capacity of prefabricated pile by CPT method are given in accordance with the complete reliability analysis. The presented research herein provides an alternative for the transition from the determinative design method of prefabricated pile bearing capacity to the probability one.

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PARAMETER SENSITIVITY ANALYSIS OF THE EFFECT OF LONGITUDINAL RESTRAINT LENGTH OF OLD STATION ON DEEP PIT DEFORMATION OF TRANSFER METRO STATION

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2004, 23 (04): -678 doi:
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[PDF 215 KB] (998)

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Due to the space restraint，new parallel transfer metro station will be built close to the old station. The divisional walls will divide the long strip pit into several small pits that will be excavated alternately to keep the old station stable and safe during deep pit excavation. The longitudinal length of the old station is several hundred meters and the nearby excavation range in the divisional walls is tens of meters，so the station deformation in the excavation is restrained by its two side longitudinal station structure. When the pit is analyzed by three-dimensional shell finite element，the longitudinal restraint length of old station is changed. The parameter sensitivity analysis is made on the effect and the reference value is proposed.

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BEHAVIOR ANALYSIS OF BURIED PIPELINE RESPONSE TO NEARBY EXCAVATION PIT WITH BRACED RETAINING STRUCTURE

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2004, 23 (04): -682 doi:
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[PDF 393 KB] (1032)

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The response of buried pipeline to nearby deep excavation in soft soil is an important project. The coupling actions of retaining structure，soil and pipeline are taken into account in this paper，and the behavior analysis of buried pipeline near deep excavation is obtained by three dimensional finite element method. The laws of buried pipeling response to deep excavation are related to many factors，such as the step of soil excavation，propping stiffness，depth of pipe below ground surface and the distance between pipe and excavation pit. The response results derived from the factors are obtained and compared，and some meaningful suggestions are proposed for engineering practice.

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STUDY ON SETTLEMENT CALCULATION OF SINGLE PILE

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2004, 23 (04): -688 doi:
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[PDF 233 KB] (1232)

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Based on Geddes stress solution and considering 3 dimensional stress of soil，a new theory on settlement calculation of single pile is presented according to Duncan-Chang constitutive model and modified layer summation. Compared with general method based on Geddes stress solution，three improvements are made，that is，(1) adopting Geddes 3D stress solution，its effect on settlement of single pile can been calculated，(2) Duncan-Chang model is used to study the settlement of pile and the nonlinear character is tics of soil can been considered，and (3) using modified layer summation，the layer character is tics and lateral deformation of soil can been computed. Therefore，the proposed method is more perfect in theory，and calculation amount is moderate to practical application.

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STUDY ON DESIGN METHOD OF TIERED REINFORCED
EARTH RETAINING WALL

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2004, 23 (04): -695 doi:
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[PDF 150 KB] (1157)

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According to the full-scale test，the theoretical value of earth pressure for lower wall of tiered reinforced earth retaining wall，based on the Boussinesq elastic theory，cannot accord well with tesing data. The result of limit equilibrium analysis shows that there are three different zones with distinct behaviours in the backfilled soil behind reinforced wall，that is，the active zone，the transition zone and the zero force zone. A new design method is proposed to calculate the additive vertical pressure of backfilled soil and the lateral earth pressure of lower wall for tiered reinforced earth retaining wall. In the method，the additive vertical pressure of backfilled soil is calculated first，and the lateral earth pressure of lower wall can be calculated based on the additive vertical pressure of backfilled soil. The comparison result with testing data shows that the proposed design method is correct and the results can be used as reference for similar retaining structure.

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ARCHING EFFECT OF ANTI-SLIDE PILE STRUCTURE AND
ITS NUMERICAL SIMULATION

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2004, 23 (04): -699 doi:
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[PDF 224 KB] (1470)

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The mechanical analysis is made on anti-slide pile with a new model of finite difference method. The analysis results show that the soil arching will be formed if the distance between piles is suitable. The mechanism of soil arching action is also analyzed，which is useful for interval designing of anti-slide piles.

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INNOVATION OF TECHNOLOGY OF PILE FOUNDATION ENGINEERING —— CAST-IN-SITU THIN WALL POT PILE TECHNOLOGY

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2004, 23 (04): -0704 doi:
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[PDF 191 KB] (1408)

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First，all the defects of existing pile foundations are set forth. Then the technological process and principle of Professor Xie Qindao¢s patent technology，i. e. pile foundation engineering innovation technology —cast-in-situ thin wall pot pile technology is specially introduced. The economical and efficient characteristics，high load-bearing capacity and good environment benefit of this technology are specially discussed by comparing with other kinds of pile foundations. The technology and economy indexes are compared and analyzed by taking Wenzhou Yince Hotel as an example. At last，the good application prospects and significance are pointed out in such fields as communication project，water conservancy project，marine engineering，and so on.

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STUDY ON RAINWASH PROPERTIES AND EFFECT OF REINFORCEMENT MATERIAL FOR HIGHWAY SUBGRADE SLOPE

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2004, 23 (04): -708 doi:
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[PDF 92 KB] (939)

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