岩土工程技术

Study of Piles Settlement Based on Static Test of Single Pile and Geddes Formula

Li Jianguang, Wang Duli

2011, 25(5): 217-220,231. doi: 10.3969/j.issn.1007-2993.2011.05.001

[Abstract](61) [PDF 633KB](7)

Abstract:
Through the in-situ static test of single pile and the settlement of single pile based on Geddes Formula,the coefficient of correction settlement is gained. The coefficient of correction settlement is applied to the settlement of piles based on Geddes Formula. The calculation method of piles settlement is reasonable through the example.

Discussion on Effects of Earthquakes on Yancheng

Chang Suping, Wang Dequ, Hao Zijin

2011, 25(5): 221-225. doi: 10.3969/j.issn.1007-2993.2011.05.002

[Abstract](40) [PDF 489KB](6)

Abstract:
This paper compares and analyzes relevant provisions of site survey roles of code for seismic design of buildings (GB 50011-2010) and code for seismic design of buildings (GB 50011-2001), Point out the relevant provisions of the modification of the division of Yancheng District, site classification, the determination of ground motion parameters, liquefaction of discrimination, soft soil seismic subsidence of the impact evaluation, etc. and some problems are paied attention to surveys in the future, gives some interrelated advise.

Comprehensive Construction Technology Study on Deep Foundation Pit Protection Close Neighbouring Buildings

Guo Hongmei, Zhang Yunkai

2011, 25(5): 226-231. doi: 10.3969/j.issn.1007-2993.2011.05.003

[Abstract](52) [PDF 823KB](5)

Abstract:
More and more requirements are put forward for deep foundation pit protection design and construction as the depth of deep foundation pit enlarges, the distance between deep foundation pit and original buildings reduces, because the buildings around deep foundation pit are highly concentrated in cities. Some successful experience for equitable design and construction of similar projects to go by is got by comprehensive construction technology study on a large-scale deep foundation pit close neighbouring buildings through the combination of field monitoring and numerical simulation.

Application of Reinforced Cement-Soil Anchor Rod on Consolidation of Soft Soil Foundation

Zhan Jie

2011, 25(5): 232-235. doi: 10.3969/j.issn.1007-2993.2011.05.004

[Abstract](43) [PDF 642KB](4)

Abstract:
Compared with supporting schemes of foundation pits in Tianjing City, the technical characteristics of reinforced cement-soil anchor rod in soft soil were introduced in detail in this paper. According to the engineer experience of supporting for soft soil foundation, some main attentions of reinforced cement-soil anchor rod technology on consolidation were analyzed.

Mountain Construction Project With Complex Geologic Conditions

Dong Zhu

2011, 25(5): 236-239. doi: 10.3969/j.issn.1007-2993.2011.05.005

[Abstract](34) [PDF 624KB](6)

Abstract:
There are a lot of digging or filling soil slope need to be analysis and tracking in mountain construction project. The most directly factor impact on the slope stability and management measures is the site planning and the geological condition. We can control the project management and investment of the slope by reasonable site planning. Based on the study and analysis, construction of a slope project with complex geologic conditions. This paper elaborates the important role of site planning in the slope project, and the influence and restraint relationship between the two.

Tangshan Steel Soil Nails in Soft Soil Foundation in the South Coast of the Application

Chen Chunjie, Li Xianjun, Sha Yuanheng

2011, 25(5): 240-243. doi: 10.3969/j.issn.1007-2993.2011.05.006

[Abstract](34) [PDF 555KB](5)

Abstract:
Introduced the steel soil nails deep excavation in soft soil along the coast in the successful application, described in detail in the construction of technological innovation and to take concrete measures to deal with. The project will use innovative steel soil nails, and steel used in the calculation process of substitution of equal area, drawing on pre-construction steel pipe pile test data, the structure of the steel soil nail to improve and optimize steel soil nail length, spacing, and steel nails and surface soil layer connection node; by strict construction of the project management and technical track, strengthen the construction of unexpected aspects of preparation, the use of information construction, the construction appeared to weaknesses in the corresponding reinforcement measures, and finally the quality of the works in strict and security control, complete the construction tasks to ensure the security pit, and schedule requirements.

The Dynanlic Compaction Experimental Research Which Used on Molding Subgrade of Soft Rock Stuffing

Li Jianwang

2011, 25(5): 244-248. doi: 10.3969/j.issn.1007-2993.2011.05.007

[Abstract](46) [PDF 513KB](9)

Abstract:
The main characteristic of soft rock is high element content, low strength, unstable feature, easy weathering and disintegration, poor adaption, which was limited on railway and highway. The stuffing's engineering character is not exactly understood, through the years' traffic circulation load or natural erosion,Serious disease will be caused by filling with stuffing's railway and highway road. This experimental research used dynanlic compaction for molding subgrade reinforcing, strengthened the density of the filled stuffing to improve its adaption, as a result, the dynanlic compaction's effect significantly after testing.

Waste Cave Stability Evaluation and Treatment Measures

Liu Dongyan

2011, 25(5): 249-251,255. doi: 10.3969/j.issn.1007-2993.2011.05.008

[Abstract](81) [PDF 603KB](9)

Abstract:
In this paper, the analysis of waste cave stability accord to Changing in the relationship between overlying rock & surface movement deformation and time,when the coal seam was mined, And simulation ground deformation using of FLAC3D after ground building load on, Determine the scope needed to deal with; On the basis of building load size and important degree, Using different grouting treatment countermeasures. Through monitoring data analysis about the goaf of overlying rock subsidence and building subsidence, Evaluation of the treatment effect.

Analysis on Bearing Behavior of Pile With Post-grouted

Zhu Dechang

2011, 25(5): 252-255. doi: 10.3969/j.issn.1007-2993.2011.05.009

[Abstract](41) [PDF 675KB](3)

Abstract:
Bored pile with post-grouted can increase bearing capacity, reduce deformation and enhance the quality of pile. In this study, static load tests on four bored piles with post-grouted and one pile without post-grouted were conducted at one construction site. By analyzing Load-settlement curves, axis force distribution of pile shaft, load of pile top and pile end, settlement of pile top over elastic compression of pile, Variation and some factors affected on load transfer of pile-soil system were discussed. This study shows bearing behavior of pile with post-grouted, which have some significance for the design of bored pile.

The Development of Indoor Model Test System for Rock-socked Foundation Pile in Karst Area

Han Xiaomeng, Zhang Huile, Zhang Zhihao

2011, 25(5): 256-260,266. doi: 10.3969/j.issn.1007-2993.2011.05.010

[Abstract](41) [PDF 788KB](5)

Abstract:
In order to make further researches on the bearing capacity of rock-socked foundation pile of karst area, a indoor model test system was established. The development system consists of the model test box, loading system, measuring system and simulation techniques of karst cave. In view of the indoor model tests of rock-socked foundation pile of karst area were less carried out, the preparing methods of making karst foundation and test operation are introduced. The final test results show that this method can meet the requirements of the following experiments. Furthermore, comparing with the full-scale load test, by use of this model test system, the test results are feasible.

Analysis of Vacuum Composite Tube Dewatering Test

Zhao Yunfeng

2011, 25(5): 261-266. doi: 10.3969/j.issn.1007-2993.2011.05.011

[Abstract](34) [PDF 758KB](4)

Abstract:
During the excavation work, low permeability of the saturated aquifers occurred often, ordinary tube well dewatering cannot drain effectively. And the residual water would bring about significant safe impact to the foundation, especially to the concealed-digging metro station and regional tunnel. Vacuum composite tube dewatering method can drain the residual water ffectively in the clay, saturated silt and aquifer boundaries, and reduce the risk about the hidden excavation structure construction.

Development and Application of Drainage Consolidation Device Used for New Type Triaxial Shear Test Samples

Zhang Jincheng, Gao Lihua, Su Zhigang

2011, 25(5): 267-271. doi: 10.3969/j.issn.1007-2993.2011.05.012

[Abstract](23) [PDF 548KB](3)

Abstract:
Triaxial shear test is one of the familiar laboratory tests in geotechnical engineering industry. The goal is primarily to obtain the shear strength index and changes of pore water pressure of soil. Shear strength indexes of total stress and effective stress could be obtained by consolidated undrained triaxial test (CU) and consolidated drained triaxial test (CD), so both of the tests have some special advantages not being replaced by other shear tests. However, the time spending on drainage consolidation during tests is too long to guarantee the progress, and consequently influences the schedule and economic benefits of the whole project. This paper presents a device which could be used to considerably reduce the drainage consolidation time of subs tan tial samples and describes its development method by analyzing mechanism of drainage consolidation process of triaxial shear specimen. Adopting this device, the efficiency of CU test and CD test could be increased 6~12 times and 3~6 times of the traditional one respectively. It could be used to significantly lower production cos ts; improve efficiency and obviously increase economic benefits.

2011 Vol. 25, No. 5