2006 Vol. 20, No. 3

Display Method:
DCM Combined With Vacuum Dewatering Treatment and Extended Bottom Rotary Jet Grouting Pile Applied to Reinforce the Saturated Soft Clay Foundation
ZHOU Jian, WANG Guan-ying, JIA Min-cai
2006, 20(3): 109-112,143.
Abstract:
DCM(dynamic compaction method) combined with Vacuum dewatering treatment and extended bottom rotary jet grouting pile is adopted to reinforce saturated soft clay foundation. The reinforcement mechanism is discussed. Combining with a reinforcement project in J iangsu province, the in-situ test results demonstrate that the method can fully exert the advantage of DCM, vacuum dewatering and rotary jet grouting pile. It shows that this method saves both time and money,and the pre-subside is controllable too.This method proposes a new way for the treatment of the saturated soft clay foundation in the coastal areas and improves in approcaches to the treatment of saturated clay.
The Engineering Specific Characteristics & Its Microcosmic Study on the Pelite in Shiqianfeng Group Upper Permian System in the North of China
XIN Min-gao
2006, 20(3): 113-116,162.
Abstract:
Based on an analytical study from macroscopically to microccosmically by virtue of an adoption of a number of means and methods, the engineering specific characteristics on pelites in Shiqianfeng group upper Permian system in northern area of China is summarized. The study on the pelite is not only of important significance on theory but also for the engineering practice.
Experimental Research on Compacting Effect of PHC Piles
YANG Sheng-bin, LI You-dong
2006, 20(3): 117-120.
Abstract:
Experimental research on compacting effect of PHC piles is significant to design and construction.To analyse the compacting effect, credible reference for engineering design and construction is provided by the aid of the test result, such as the parameter changes of in-situ foundation, the observation of piles construction and the measure of pore water pressure.
Realization of Slope Failure Pattern Recognition System
BIAN Ya-dong, ZHANG Yu-guo, CHANG Li-wu
2006, 20(3): 121-123,146.
Abstract:
The slope failure pattern recognition system regards rock mass structure as the basic controlling factor, and, considers the feature of rock mass, the shape of structural plane and the structural parameters of slope at the same time. The system organically combines between pattern recognition technique and expert system, and five lypes of rock mass slope are detemiined. It has advantages such as combining with project closely, obtaining the quantitative result, plain inference rule and convenient application. It proves the system's practicability and effectiveness that the result is in accord with the practical situation.
Treatment Methods of Karst Foundation in the Plant Site of Pingguo Aluminum Factory
CHEN Xin-hua, PENG Zhen-bin
2006, 20(3): 124-127.
Abstract:
On the basis of collecting and studying the geotechnical condition in the plant site of Pingguo aluminum factory sufficiently, the karst ground characteristic is set forth. Summarizing and investigating the treatment methods for the karst ground characteristic in Pingguo aluminum factory,scientific basis for system investigation of ground treatment in karst area is provided.
The Design and Actualization for the Model Experiment on Underground Water Uplift Action Mechanism
ZHANG Bin, LI Guang-xin, YANG Jun-feng
2006, 20(3): 128-131.
Abstract:
With the development of urban, city space becomes less and less, and underground space is used more and more. However, it is concerncd with dynamic change of underground water, which often brings about series of geotechnical engineering problems. And anti-floating evaluation of underground structure is one of the significant questions. Regarding this, clear rules haven't been given by existing criterion, and people's attitude on it is also quite different. And the systematic experiment is less than theoretical research. This article introduces the whole idea, tester design and actualization process of the model experiment for uplift action mechanism of underground water.
Experimental Research on Strength of Cemented Red Clay
GUO Pei-xi, RUAN Huai-ning
2006, 20(3): 132-135.
Abstract:
This kind of soil is formed during the chemical weathering of carbonate rocks.It exhibits high water content and high plasticity. When structures are constructed on red day foundations, the soil often needs to be treated due to its soft properties, Although the method of mixing of rail and cement is commonly used to improve soft soil, intensive studies on its affect are relatively few. Unconfined compression tests are performed on the cemented red clay. The basic mechanics parameters of this kind cement soil can he got by experiment. After the regression analysis of the experimental result,it can he given that influence factors for cement soil strength and relation between it,and the strength calculate formulas of different cement contents and cure ages.
Study on the Collapsiblity of Gravel Soil Foundation
ZHANG Guan-hong, CHEN Wen-wu, WANG Sheng-xin
2006, 20(3): 136-139.
Abstract:
Based on the ponding loading test of Gannan 330kv transformer substation's foundation, the collapsible mechanics of gravel, soil is analyzed by the structure theory of soil's collapsible deformation and the main factors of gravel soil's collapsible distortion. And it's pointed out that the collapsibility is mainly due to the special structure of gravel soils which including big grain framework structure and granule cementation which filled in the big space. Because of gravel soil's main framwork's compressive and shear strenth decreased, the stucture of it is damaged too. Then the second collapsiblity come into being.
The Optimization Design of the Inverse V-shaped Anti-slide Pile
WANG Xun, LI Yun-hua, LI Shu-sheng
2006, 20(3): 140-143.
Abstract:
Based on the vertical elastic foundation beam theory and the ANSYS platform, the inverse V shaped structure optimization design variable computation model is established by the APDL language. Through the ANSYS optimization analysis, the superior section combination model is found. It can be repeatedly used and the optimization process is sped up with the help from the VB program.
Study on the Water Influence on the Acoustic Wave Velocity of Different Rock
WANG Yu-xia, XU Bo-tao
2006, 20(3): 144-146.
Abstract:
Based on the analysis on the acoustic wave velocity of different origin rock, the water influence on the acoustic wave velocity of different rock is provided. Analyzing the development degree of rock pores and microfissures as well as the rock hydraulic properties, the variance rules of rock acoustic velocity under the action of water are explained.The development degree and hydraulic properties of the rock microfisaures can be judged preliminarily by using these rules.
Grain Breakage Effect on the Permeability Properties of Coal Gangue
WANG Feng-jiang
2006, 20(3): 147-150.
Abstract:
Normal test method is employed to explore the relationship between dry density and optimum water content of coal gangue used in darning. The results show that the compaction will change the distribution of grain size, the particle size distribution will be more satisfactory and get a higher degree of consolidation. When the content of coarse grain is great than 60 %, the crush degree is observably increasing. When the content of coarse grain is less; than 40 %, the leading engineering characteristic of coal gangue is determined by fine grain. The coefficient of permeability of coal gangue can be defined as an exponential expression of void ratio. With tbe increasing of fine grain, tbe penetrability of coal gangue will be clearly lower.
Analysis on Testing Results of the Airport Runway Foundation Reinforced With Vibro-compaction Gravel Pile
SHENG Chu-gen
2006, 20(3): 151-153,158.
Abstract:
Treatment effects of the airport runway foundation reinforced with vibrc-compation gravel pile are discussed, Bseed on data of drilling sampling tests and in situ tests, the variation rules of pore water pressure before and after the treatment are analyzed. Physical and mechanic property indexes of soil before and after the treatment are compared, and probability of sand seismic liquefaction are proposed. Some conclusions are given, which can provide reference for other engineering.
Development on the Analysis of Rockburst Under Unloading Conditions and Its Prospect
CUI Dong-liang, LI Xi-bing, YE Zhou-yuan
2006, 20(3): 154-158.
Abstract:
Rockburst is met under the unloading conditions during the excavation of underground cavity in high geostrese areas, whose characteristic relate closely with the characteristic of rock breakage in unloading conditions. On the base of reviewing current status of unloading rock mass mechanics for rockburst, the main problem are presented from experimental research and theoretical investigation. Some opinions are brought forward.
Analysis on the Tunnel in the Filling Karst Under Complicated Geological Conditions by 3D Finite Element Method
ZHANG Zhi-qiang
2006, 20(3): 159-162.
Abstract:
The filling karst raft roadbed reinforcement of the tunnel bottom in DK278 + 628- + 698 section of a railway is analyzed by three dimensional elasto-plastic contact finite element method. The Drucker-Prager model and elastic-plasstic contact model is used in simulating the stress, deformation and strain of the tunnel. And the resuh has guiding significance on the engineering.