岩土工程技术

Mechanism Analysis Based on Sub-section Method of Slices for Slope Stability Calculation

LIU Zi-zhen, YAN Zhi-xin

2006, 20(5): 217-220.

[Abstract](128) [PDF 201KB](7)

Abstract:
The method for slope is generalized according to the basic analysis thought of rigorous generalized method of slices. It is a subsection method of slope. The author rebuilt each equation under limit equilibrium method. On this basis, an effective simplified algorithm is applied for slope stability analysis. That is the relations function of inter-slice force between tangential grinder and normal direction on the regulation of Mohr-Coulomb. Through study and analysis of a case, the safety factor of subsection method forslope is fairly close to the result of generalized method of slices. The computing result shows the presented method is applicable.

File Storage Format of Seismograph and GPR and Its Reading Method

YANG Tian-chun, WANG Qi-ren, LIU Xin-hua

2006, 20(5): 221-224.

[Abstract](44) [PDF 336KB](8)

Abstract:
Recently, many instruments of seismograph and GPR are imported. Manufacturers unusually provide the file format. The authors study the file format of SEG-2 data, and write a corresponding routine for reading the data in Matlab programming language. A practical application is used for the reading routine. The results show that the route is correct, and this route is easy to maintain and require a minimum of revision for a kind of instruments' SECt-2 files.

Application of the Multi-electrode Resistivity Method in Geotechnical Investigation for Weathered Rock Site

LIU Fa-xiang, HE Peng, XIAO Yun-kai

2006, 20(5): 225-228.

[Abstract](55) [PDF 478KB](7)

Abstract:
Generally, due to the characteristic with nonuniformity of the weathering action in weathered rock site, Chinese standard "Code for investigation of geotechnical engineering (GB 50021-2001)" stipulates sternly the space of the exploratory hole in this kind of sites, bringing on large numbers of the exploratory holes. In this study, analyzing the feasibility and the necessity of multi-electrode electric method while carrying out geotechnical investigation in this kind of sites and using the example of the geotechnical investigation for a refinery site in Algeria, the optimization of multi-electrode resistivity method on the geotechnical investigation scheme for the large-scale weathering rock mass site is explained.

Curved Pipe Jacking Technology and the Calculation of Jacking Loads for Curved Section

MA Bao-song, ZHANG Ya-chun

2006, 20(5): 229-232,259.

[Abstract](60) [PDF 349KB](8)

Abstract:
Because of the advantages and application fields, curved pipe jacking technology is paid more and more attention . The application of curved pipe jacking techniques all over the world is reviewed. Based on the two examples of "SS MOLE" and "Ultimate Method" curved pipe jacking techniques, the author introduces the suitable soil conditions, reasonable pipe diameter can be installed,application field and the minimum curved radius for curved pipe jacking technology. In order to solve the key and difficult problem of jacking loads calculating,an equation for the jacking loads calculation during curved section driving is given,as well there is an example shows the application of this equation.

Research on Rock Burst Criterion and Forecast in the Tunnel of Xihua Mountain

HAN Zhi-qiang

2006, 20(5): 233-236.

[Abstract](48) [PDF 373KB](5)

Abstract:
Rockburst is a serious geologic hazard that endangers greatly the security of operators and facilities involved in the production. The definition of rock explosion with its occurring laws of nature, its character is discussed. With the criterion for rock burst and some thoerotical analysis, through numerical simulation software, the conclusion upwards is also validated.

Application of Algorithm Neural Network Method in the Prediction of Loosen Zone Around Roadway

XUE Xin-hua

2006, 20(5): 237-239,266.

[Abstract](40) [PDF 393KB](4)

Abstract:
Considering some defects of BP Neural Network, the idea that the power size and the threshold value of the network structure is optimized by combining genetic algorithm with neural network is presented. Based on genetic algorithm, the prediction model of loosen zone around roadway is built. Finally, the prediction on the thickness of the loosen zone around roadway is made with this GA- BP model, and the results are compared with the BP predicting results. The result shows that the GA- BP model is reliable and precise, and it is effective and feasible to predict the thickness of the loosen zone around roadway.

Determination of Parameters for Beta Distribution and Its Application in Geotechnicai Engineering

LIU Yong, ZHENG Jun-jie, GUO Jia

2006, 20(5): 240-243.

[Abstract](42) [PDF 213KB](5)

Abstract:
This paper statistically analyses the spatial probabilistic characteristics of random variables in geotechnical problems. Both the iteration process to determine the parameters for a beta probability density function and the empirical formula to simplify this iteration are presented. Therefore, the estimation of the lxxmds of random variables is handled efficiently and the applicability of the beta distribution in reliability analysis is illustrated. Certain other types of distribution are chosen to fit the same random sample for comparison and the results prove that the beta distribution is superior to others.

Stability Analysis of Surrounding Rock of Circular Surge Shaft in Fissured Rock Mass

HAO Jian, HE Peng, WU Sai-gang

2006, 20(5): 244-247.

[Abstract](72) [PDF 359KB](4)

Abstract:
Block theory is an effective and reliable engineering analysis method for the stability of fissured rock mass. Based on stereographic projection,an analysis is made for the stability of random blocks in surrounding rock of a certain circular surge shaft of a hydropower station. During the study with stereographic projection cylindric free surface is simply converted to eight walls. Potential key blocks and their moving modes are studied and the values of sliding force of those blocks are worked out. This could be a direction to the design of excavating,anchoring and permanent lining of those walls,and also a reference to similar projects.

Theory and Application of Composite Foundation With Gravel Pile and CFG Pile

WANG Gui-he, JI Rong-sheng, MA Xiao-chun

2006, 20(5): 248-251.

[Abstract](56) [PDF 259KB](9)

Abstract:
The application and the design calculation methods of composite foundation with gravel pile and CFG pile based on engineering practice are analyzed, and the rational calculation methods are presented.

Study on the Location of the Maximal Lateral Displacement of Soft Soil Foundation Under Embankment

LIU Jin-long, XIA Yong

2006, 20(5): 252-255.

[Abstract](34) [PDF 339KB](5)

Abstract:
It is important to define the location of the maximal lateral displacement of soft soil foundation, which affect the dispesal of inclinometer pipe and holding the character of deformation exactly or not. Based on nonlinear finite element method, the character of lateral displacement of soft soil foundation with stage eonstruction is analyzed. It is shown that the location of the maximal lateral displacement is changeable at different eonstruction stages, which more likely lies in the vertical surface between the toe and the middle of slope of embankment. In order to get the maximal lateral displacement reasonably, it is suggested that the inclinometer pipes should be placed in the area between the toe and the middle of slope of embankment. It is also shown that the lateral displacement can not be measured eonveniently with inclinometer pipe, although which has been used in engineering widely, for there are many shortcomings within this technique. So, the technique and instrument should be improved to measure lateral displacement accurately.

Testing Study on the Characteristic of Shrink-swell for Expansive Soil

MENG Qing-yun, YANG Guo-lin

2006, 20(5): 256-259.

[Abstract](43) [PDF 196KB](7)

Abstract:
Based on lots of laboratory tests of Nan(ning)-You(yiguan) expansive soils, the relationship between shrink-swell and time of expansive soils is researched. The similarities and differences between shrink and swell are found. The quantitative correlation between deformation magnitude with different original water content and dry densities is explored.

Influence Analysis on Soft Soil Creep to Adjacent Ground Settlement of Deep Dit

HUANG Geng-cai

2006, 20(5): 260-262.

[Abstract](53) [PDF 275KB](6)

Abstract:
The relation between horizontal value behind of the diaphgram wall and settlement of the ground behind the diaphgram wall analyzed, based on the field investigation and previous research. Fitting the horizontal displacement with secondary curve, supposing ground settlement curve could be described by normal distribution density function. The maximum ground settlement can be calculate using ground-loss method in every case. And then it is compared to the maximum value measured in the field. The delay effect of creep of the soft soil to the ground settlement is presented.

Development of Software Slide CAD for Slope Stability Analysis and Treatment Design

WANG Xun, ZHANG Bin, SONG Bao-qiang

2006, 20(5): 263-266.

[Abstract](51) [PDF 561KB](7)

Abstract:
The side CAD software development method and its main function is systemically elaborated, and its usability is emphasized. The software includes font module, solution module and post-processing module, which maintains the interactive input. Sorts of slope computation methods and search algorithms are provided. Meanwhile, cantileverde anchor cable and inverse V-shapde anti-slide pile optimization designs are provided.

Prevention and Remediation of Slope Failure in Hong Kong

ZHU Hong-hu, QIAO Zhong-fa

2006, 20(5): 267-271.

[Abstract](57) [PDF 754KB](11)

Abstract:
LandsLides happen frequently in Hong Kong. Effective measuments are adopted to prevent landslides. The causes of slope failure, preventive measurement and slope management systems are discussed. Hong Kong experience in slope engineering provides valuable information for main land China.

2006 Vol. 20, No. 5