2012 Vol. 26, No. 4

Development and Creation
The Analysis of Microstructure Characteristic Parameters of Kunming Laterite
Jin Kesheng, Huang Ying, Chen Xiaona
2012, 26(4): 163-168. doi: 10.3969/j.issn.1007-2993.2012.04.001
Abstract:
Exceptional physical and mechanical properties of laterite is mainly determined by the micro-structure characteristic of it. This article analysed mierostructural characteristics of Kunming laterite under the electron microscope, extracted from the processed photos in the microstructure of laterite. The average perimeter, the maximum area, the degrees of roundness, the degrees of complexity, the degrees of directed and quantitative parameters of fractal dimension and distribution, and also the quantitative parameter associated with the physical and mechanical properties of laterite.
The Natural Consolidation Characteristics And Mechanism And Its Utilization of The Plain Fill
Zou Qiongyan, Luo Zhaohua
2012, 26(4): 169-172. doi: 10.3969/j.issn.1007-2993.2012.04.002
Abstract:
Engineering test results showed that: plain fill under the natural state will produce the consolidation, but affected by their own gravity and also by rainwater infiltration, exposure to sun and wind drying and other factors. The upper part is mainly influenced by rainfall infiltration, exposure to sun and wind drying effect, while the lower part mainly affected by gravity. So the fill of this consolidation is not simply the self-weight consolidation, we refer to as the natural consolidation. The results also show that: after a certain period of time, in rainwater infiltration, exposure to sun and wind dried under the action of a certain depth, the upper part of the fill consolidation degree is better, and the formation of "crust", the filling time of four years the fill in the depth of 6 meters, its mechanical properties equivalent or close to compaction energy for 2160kN · m tamping and filling, so it can be used for settlement sensitivity requirements of light low buildings and roads. For the bearing stratum of pile load, it lower project cost, and is safe.
Designs of Pile Ccombined with Three-Axis Mixing Pile and Bracing System in Deep-Foundation Pit
Yao Ping, Zhao Shengfeng, Zhang Xin
2012, 26(4): 173-176,180. doi: 10.3969/j.issn.1007-2993.2012.04.003
Abstract:
Deep foundation pit is a high-risk project, in which the theories are complex and discipline is highly comprehensive. It often appears bracing system instability, retaining structure instability, pit wall leaking , bottom uplift and so on. Combined with a project example in Shanghai, the main points of selecting scheme of foundation pit support were analyzed. And the key calculations and checking content in the design of retaining structure are Summisized. Finally, design calculation results and the practical monitoring data results are compared. The conclusion had proved the effectiveness of retaining form. It provides some suggestions for same type of deep foundation pit projects.
Technology Probe and Research
In-situ Immersion tests and analysis of MedioPleistocene Q2 loess at Xi'an Tabldand
Shi Huaiqing, Zhang Jiwen, Wang Donghong
2012, 26(4): 177-180. doi: 10.3969/j.issn.1007-2993.2012.04.004
Abstract:
By using a larger immersion test pit in Xi' an loess tableland, collapsibility of Q2 loess under overburden pressure was researched, and its Particular Characts of collapsibility was thoroughly analyzed, all of which will give a guidance to the determination of collapse pattern of similar sites.
Theoretical analysis on the influence of ground surface subsidence caused by the self-walking TBM
Lu Qingguo, Zhang Yaoqing, Niu Fangqiao
2012, 26(4): 181-184. doi: 10.3969/j.issn.1007-2993.2012.04.005
Abstract:
Through studies on the ground surface deformation that the self-walking TBM drills in the ground by climbing. The relevant results show that., the longitudinal settling tank curve over the self-walking TBM track is similar with the settling tank curve that the stochastic medium theory predicts; There is a large deviation between the transverse settling tank curve being formed when self-walking TBM is covered shallowly and the theory of normal distribution; the earth's surface soil is deformation being embedded of the ring resistance structure on some degree.
Reinforcement Design and Crack Causes Analysis for Underground Storage Cavern Structure
Shi Weimin, Yang Zhi, Shu Yunzhong
2012, 26(4): 185-187,191. doi: 10.3969/j.issn.1007-2993.2012.04.006
Abstract:
Based on the analysis of crack causes for underground storage cavern structure, the methods according to the space were to added on the second lining in underground storage cavern. The calculation methods for determining the space between the second lining was putting forward by controlling the crack not existing in the original concrete lining, and the load calculation formula of second lining was reduced by using the compatible displacement conditions of composite members, put forward a design method reinforced the underground storage cavern by adding second lining.
The Improved Anti-Sliding Calculation Method of Gravity Retaining Wall
Zhang Yundong, Ma Shuzhi, Wang Gang
2012, 26(4): 188-191. doi: 10.3969/j.issn.1007-2993.2012.04.007
Abstract:
The present anti-sliding stability calculations of gravity retaining wall has some defects. This paper had divided the retaining walls that buried into earth in small grid. By searching for the point of minimum stability factor against overturning. This point is the actual turning point of the retaining walls. According to the location of this turning point, both sides of the wall are divided into four sections in order to calculated the earth pressure. At the end of the analysis, combining the friction of soil and foundation wall to get the improved anti-sliding stability factor formula. This article also, analysised the location of the minimum turning point of overturning and the anti-sliding coefficient of stability, and how they change with the change of retaining walls, width and depth that buried into earth.
Theory and Practice of the Bursa seven-parameters for transfer function model in The Field Verification in National Mining Rights
Wang Lichao, Lv Xuejun, Wang Fuzeng
2012, 26(4): 192-195. doi: 10.3969/j.issn.1007-2993.2012.04.008
Abstract:
This paper indicated the Bursa seven-parameters of the transfer function model,the coordinate system trans formation methods, the common point selection and accuracy assessment. As well as the Bursa seven-parameter transformation model make a instance of calculations that Coordinate System Transformation by 1954 Beijing and 1980 Xi'an in The Field Verification of The National Mining Rights.
Numerical Analysis Method of Explosion Wave Effeetion on Underground Structure
Zhang Bei, Xu Zenghui
2012, 26(4): 196-199,207. doi: 10.3969/j.issn.1007-2993.2012.04.009
Abstract:
Using Dynamic finite element program, explosive elements are directly applied in rock elements to present the explosion in rocks and blast wave spread to underground structure. Results from numerical calculations of an explosion experiments showed the measurement relevant results. The method using Dynamic element program to simulate explosion loads effecring on underground structure is workable, this method can be adopt further to study the underground structure upon dynamic character and safety on explosion loads.
Waves penetrating tests of the quality analysis and discretion in pile foundation
Zhao Jianhua, Zhou Chongliang
2012, 26(4): 200-203. doi: 10.3969/j.issn.1007-2993.2012.04.010
Abstract:
This Article described a base ultrasound tests, the principles and so on. Through an ultrasound several acoustic parameter from the qualitative and quantitative analysis and judging the whole body integrity, defects and deficiencies levels. In general, it determined by the examples from the qualitative and quantitative tests judged in the case, and take appropriate treatment measures.
Application of Large Diameter Tube Well Dewatering in Subway Construction
Ma Jian, Feng Keming
2012, 26(4): 204-207. doi: 10.3969/j.issn.1007-2993.2012.04.011
Abstract:
As one of groundwater control measures, the lager diameter tube well dewatering is applied widely and ma turely. Because of the low criteria of construction admittance, and the little proportion in the construction cost, quality control is often ignored. It causes slope instability and bottom plate uplift frequently. It's necessary to design based on hydrological parameters from pumping test, control construction quality strictly for achieving satisfied effect.
The calculation analysis on the settlement of the soft soil foundation in sea embankment construction
Meng Guangqing, Cheng Peng
2012, 26(4): 208-211. doi: 10.3969/j.issn.1007-2993.2012.04.012
Abstract:
Based on the analysis of the concepts of settlement and consolidation, the applicability of the traditional settlement calculation formula has been studied. For the sea embankment engineering practice problems, the cautions and suggestions of the soft base embankment engineering practice analysis been pointed out, which can benefit the further studies.
Real Heaped Load Tests of Reinforced Concrete Beams With Carbon Fiber Sheet
Zhou Jiang, Shi Qunfei, Wang Wei
2012, 26(4): 212-214,217. doi: 10.3969/j.issn.1007-2993.2012.04.013
Abstract:
Real heaped load tests were conducted for the beams randomly selected from reinforced concrete beams of a project, which designed to he strengthened with Carbon fiber sheet. The deflection, crack growing and the bearing capactity of these were analyzed and effect of this method was appraised, which might provided a reference for other colleagues.
Comprehensive Treatment Methods For Pile Construction of Application In City Areas
Huang Luming, Tu Xiaofang, Liu Haisheng
2012, 26(4): 215-217. doi: 10.3969/j.issn.1007-2993.2012.04.014
Abstract:
For the project DeShengMen Inside street in Beijing bridge pier construction process. Not only it meet the heavy traffic,narrow,overground and underground obstacles and many other conditions,but also,meet many Original river way Reinforcement material, Poor construction conditions and difficulty in construction is extremely high, and in various way, Measuring through eventually Solve these problems. For a completed bridge pier construction task, in my opinion, In the old city complex area construction, Comprehensive treatment measures consist better development space, Worth researching.