2006 Vol. 20, No. 4

Display Method:
Study on the Bearing Capacity of Bottom-consolidated Pipe Pile
LI Lian-ying, BAI Mu, ZHAO Zhi-feng
2006, 20(4): 163-165,169.
Abstract:
Based on field tests of prestressed concrete pile that bottom soil is consolidated by high pressure rotary jet grouting. The mechanical property of the pipe pile that there is cement soil under the tip and how it effects on the pile tip resistance and single pile ultimate bearing capacity is studied. The applicability of bottom-consolidated pipe pile in Tianiin is discussed.
In-situ Geostress Test by Rock Acoustic Emission Based on Wavelet Packet Analysis
WANG Geng-feng
2006, 20(4): 166-169.
Abstract:
Aimed at the difficulties to determine Kaiser point of rock acoustic emission, wavelet packet analysis is put torward. Based on acoustic emission tests of sandstone specimens under uniaxial compression. First AE (acoustic emission) signal noise reduction method for Kaiser point using wavelet packet is presented. Then get the frequency of AE signal. Last, using the wavelet packet analysis study the energy distributions of AE signals and the characteristic frequency band of Kaiser point are obtained. Results show that wavelet packet analysis is an effective way in processing of rock AE.
Experimental Study on the Bearing Capacity of Bucket Foundation in Saturated Sand
LU Xiao-bing, JIAO Bin-tian, LIU Liang
2006, 20(4): 170-172,199.
Abstract:
Bucket foundation is a new type of foundation which may be used extensively in offshore structures. It is attracted by oil corporations and researchers because of its several advantages. The static bearing capacity of bucket foundation is studied by experiments of single-and four-bucket foundation in saturated sand layer. The characteristics of bearing capacity under vertical load and horizontal load are obtained experimentally. The horizontal load of four-bucket is applied in the direction parallel to one sideline or one catercorner of the quadrangle formed by the centers of four buckets. The load-displacement curves are obtained. The characteristics of single-bucket and four-bucket foundation, the effects of load direction and load rate are analyzed.
Dewatering Technology of Vacuum Deep Well and Its Application Study in the Construction of Metro Engineering in Beijing
WANG Guo-feng, PAN Xiu-ming, WANG Gui-he
2006, 20(4): 173-178.
Abstract:
By Studying working section engineering instances of vacuum dewatering at Jinsong station re-entry line and Andingrnen-Beitucheng station interval in the first-stage construction of Beijing Metro 10th Line, the operating theory of vacuum deep well dewatering technology, and its performance, applicability, construction effectiveness is discussed. Through studying engineering instances, the new technology is proved to be effective, that could overcame the problem of complex stratum dewatering in the construction of underground and to fill up the blank of dewatering technology of underground construction in Beijing.
Research and Application of Vertical Cut-off Wall Keyed into Impermeable Stratum
MA Jin-pu, ZHANG Qing-yu, JIA Li-hong
2006, 20(4): 179-182.
Abstract:
The form and application conditions of vertical cut-off wall keyed into impermeable stratum are discussed. And it is successfully applied in a foundation pit project. The slope stability and the safety of building construction and buildings around is assured too.
Application of Soft Soil Foundation Treatment With High Vacuum Densification Method in a Ship Yard
GAO Tang
2006, 20(4): 183-185.
Abstract:
The data and results of field tests show that the high vacuum densification method is good at soft soil foundation treatment and it has a momentous engineering value and spreading significance.
Application of Joint-piles Technique in Deep Foundation Pit Bracing Project
PENG Yuan-gui, LUO Ming-liang, LIU Xiang-lei
2006, 20(4): 186-189.
Abstract:
Through real project introduction, the application of joint piles technique in deep foundation pit bracing project and the key points of related construction techniques are discussed. By prolonging the solidified time of concrete, the joint effect of neighborhood piles got successfully strengthened.
Application of Comprehensive Index Method and AHP Method in Comprehensive Assessment of Geologic Hazards
PENG Man-hua, TANG Xiang-da, XU Si-yi
2006, 20(4): 190-193.
Abstract:
Aiming at the ruzziness existing in the comprehensive assessment of geologic hazards, the calculation method and procedure of comprehensive index method and AHP methhod in comprehensive assessment of geologic hazard is introduced. The method is expounded by engineering practice.
Fuzzy Random Reliability of Prestressed Concrete Pipe Piles in Wuhan Area
ZHENG Jun-jie, HE Chun, LU Yan-er
2006, 20(4): 194-196.
Abstract:
Considering the randomness and fuzziness of the failure of piles, the settlement rate of piles is taken as a fuzzy random variable by using related theory of fuzzy mathematics. The membership function is determined by fuzzy statistical analysis of 42 static load tests of prestressed concrete pipe piles in Wuhan area. The probability formula and the calculation method of reliability index are derived by assuming the probability distribution of settlement rate and using the probability theory of fuzzy event. It provides reference for the judgment of failure of piles in engineering practice.
Main Engineering Geological Problem in Trench Inspection and Its Treatment in Beijing Region
WANG Hong-yin
2006, 20(4): 197-199.
Abstract:
Through the practice of the trench inspection in Beijing region, the main engineering geological problem and its treatment is introduced. The practice is worthwhile for reference.
Analysis of the Fuzzy Reliability in Geotechnical Engineering Based on Choosing the Membership Functions
SUN Jie, MOU Zai-gen, ZHANG Xiao
2006, 20(4): 200-202,207.
Abstract:
The fuzzy probability of two typical structures in geornechanics engineering, underground diaphragm wall and retaining wall, is calculated by three representational membership functions and a probability density function for the performance function. Then some useful conclusions on choosing the optimal membership function are obtained.
Effects of Moistening and Demoistening of Collapsible Loess
JIN Meng-xiong
2006, 20(4): 203-207.
Abstract:
Collapsibility of loess is inconstant. Effects of moistening and demoistening, caused by obvious variety of water content of loess, influence strongly to collapsibility of loess. When proceed to the evaluation to collapsibility of loess, should pay attention to synthetically analyse and estimate disadvantageous influences, caused by effects of moistening and demoistening, with the dynamic point of view and method, in order to adopt to effective measure to dissolve hidden trouble to engineering.
Analysis on Single Pile Vertical Static Load Test Result in Superficial Part Hard Soil in Shanghai
ZHU Huo-gen, WANG Zhen-nan, FU Xi-liang
2006, 20(4): 208-211.
Abstract:
Based on analyzing the destructive static load test results, the failure patterns of single pile in superficial part hard soil area is approached. The research will benefit in determining the influence of the chooaing of certain ultimate friction resistance and the quality assurance for sinking pile on the test results.
Application of RTK Technique in Engineering Setting Out
WANG Sheng-guo, YAO Pei-jun
2006, 20(4): 212-214.
Abstract:
The theory of RTK (Real Time Kinematic) is described. Based on the engineering practice,RTK shows advantage in engineering setting out.
Problems in Detailed Geotechnical Investigations of Linked High-rise Buildings
ZHOU Ai-qi, XU Wei
2006, 20(4): 215-217.
Abstract:
The types, plane distributions, structural patterns and load-bearing characteristics of linked high-rise buildings are summarized, and the main geotechnical problems are analyzed at the perspective of geotechnical investigations. It is expounded that the main point of investigation should be held if pile foundation is potentially used, which may be referenced in the investigations of similar buildings.