岩土工程技术

Design and Calculation Method for Steel Pipe Wall Thickness by Jacking Installation

Chen Jiguang, Qu Yan

2016, 30(6): 271-274,285. doi: 10.3969/j.issn.1007-2993.2016.06.001

[Abstract](102) [PDF 1401KB](20)

Abstract:
For steel pipe line which is welded joint to a line and launched by jacking method, the incurred stresses under launching and service period are quite different from precast reinforced concrete pipe. Based on machenics theories, accounting for the characteristics of surrounding forces on pipe and displacement of the pipe under jacking or service periods, the designer presents new method to calculate stresses, offers several formula. There are also modifications presented for the comtemprary design specification in transverse earth load calculation formula.

The Prediction of Raintorm Debris Flows Characteristics about Large Dump Based on Solid Sedimentary Analysis——Take the Mine Debris Flow in Sichuan as an Example

Hu Yide, Yu Haidong, Yang Tao

2016, 30(6): 275-278. doi: 10.3969/j.issn.1007-2993.2016.06.002

[Abstract](29) [PDF 956KB](8)

Abstract:
The debris flow as a common geological hazard has become one of the most harm geological hazards to human. At present people's understanding degree to the research on debris flow is relatively weaker than the study about collapse, landslide and flood. This paper takes a mine debris flow as an example based on solid sedimentary analysis, predicting the flowing characteristics of rainstorm debris flow of large dump, studying the dilute resistance and solid sedimentary law of the low viscosity debris flow. We have used the solid deposition analysis method to calculate the weight of debris flow, velocity, solid flow and total flow rate. Analysis on the process of the debris flow which evolved into a torrent due to some unfavorable factors attenuation such as channel has gotten slowly. The research results have important and practical guiding effect about prediction and prevention of debris flow.

Discussion on Geotechnical Engineering Issues with Tailings Embankment

Zhao Junying, Liu Hua

2016, 30(6): 279-281. doi: 10.3969/j.issn.1007-2993.2016.06.003

[Abstract](39) [PDF 496KB](11)

Abstract:
In recent years, some tailings pond serious accidents have occurred now and then in China, and lead to serious threat or damage to the people's lives or property. So the geotechnical engineering issues with tailings embankment is the key of tailings pond's stability analysis and evaluation for tailings pond's safe operation, reduce the occurrence of serious accidents. This paper explores the application of geotechnical engineering issues' technology in tailings embankment, and the conclusion could serve as reference for engineering issues with tailings embankment.

Zhongwei Ningxia Section of the Great Wall Yaotan Square Mound Disease Investigation

Tang Zhiliang

2016, 30(6): 282-285. doi: 10.3969/j.issn.1007-2993.2016.06.004

[Abstract](34) [PDF 2687KB](9)

Abstract:
The quartet Mound wall belongs to the west of the Great Wall in Zhongwei, Ningxia The Great Wall in Ningxia west built in the era of Emperor Hanwu, is a part of the Great Wall of the Han dynasty, due to wind erosion, freezethaw, rain erosion, flood washing, sand buried, such as the destruction of the natural role, and the bees, mice to make holes in the wall, vegetation root chopping, such as the destruction of the biological effect, this article finds out site the barbican, castle, the Great Wall of the kinds of diseases and their potential risk, and carries on the qualitative analysis, puts forward the prevention and control measures; finds out the physical and mechanical and chemical properties of rammed earth wall, to repair prolec engineering detailed engineering geological data and the design of disease investigation and study for the design of the required technical parameters.

Numerical Simulation of Tunnel Deformation in Clay Induced by Normal Faulting

Huang Hui

2016, 30(6): 286-289,292. doi: 10.3969/j.issn.1007-2993.2016.06.005

[Abstract](41) [PDF 1317KB](7)

Abstract:
Damage of tunnel in clay induced by underlying normal faulting is not tully understood. I his study carries out a numerical study on this problem using total stress analysis method. Both of the calculated results and centrifuge data show that deformation of the clay layer is classified as a stationary zone, a shearing zone and a rigid body zone. The area of differenti al, ettlement zone decreases with depth, resulting a reduction in area of influencing zone and an increase in extent of damage with depth. When the tunnel surface is tied to the surrounding soil, the tunnel nearby the bedrock fault is mainly suhiected to bending while the area far from the bedrock fault is mainly subjected to tension. At the tunnel crown, tension strain is observed on the footwall side while compression strain on the hanging wall side.

Stability Evaluation on Combat Readiness Tunnel of Deshengbu Village in Wanquan County

Zhou Pengfei, Liu Chun, Zhang Jilu

2016, 30(6): 290-292. doi: 10.3969/j.issn.1007-2993.2016.06.006

[Abstract](32) [PDF 1008KB](7)

Abstract:
There are a great many combat readiness tunnels in the villages of Wanquan county. Some of them have e volved to land collapse. The increasingly growing of land collapse becomes a great hazard to people's lives and property. We studied the stability of combat readiness and analyzed the influencing factors of the land collapse in this article.

Research on Bearing Capacity of Shallow Silty Clay and Shallow Foundation in Shenyang

Sun Feng

2016, 30(6): 293-297. doi: 10.3969/j.issn.1007-2993.2016.06.007

[Abstract](40) [PDF 731KB](14)

Abstract:
Using statistical regression analysis, mechanical parameters and bearing capacity of the regional silty clay were studied based on engineering geology and bearing capacity data from 28 sites in Shenyang. Based on the unified strength theory to improve Terzaghi theory, the empirical formula of bearing capacity of shallow foundation in Shenyang area is established. The research show that: within the study area of shallow silty clay, the variation of the physical parameters is small, the correlation of the physical parameters is conspicuous, the variation of the mechanical parameters is large, and the cor-relation of the mechanical parameters is not conspicuous. There is a linear relationship among the standard penetration test values,lateral pressure test values,and soil test parameters values with the bearing capacity of the shallow silty clay, plastic index and static side pressure coefficient. The regional empirical formulas of bearing capacity and the bearing capacity formula of Shenyang area of shallow foundation to establish improved Terzaghi theory, and the actual bearing capacity have higher uniformity. The research results can provide necessary references for the reliable design of regional foundation and determination of bearing capacity.

The Geological Disaster Risk Assessment and Management Research

Hu Donghua

2016, 30(6): 298-302. doi: 10.3969/j.issn.1007-2993.2016.06.008

[Abstract](33) [PDF 3053KB](8)

Abstract:
In the region, for the geological disaster's forecast is that it's an important work for the city's programme and the select in the project engineering. This article is mainly for the concept's analysis in the risk of the geological disaster and it's have a systematic research in the geological disaster's risk assessment, management and so on. What's more, it's have a widely generalize for the evaluation methodology,type, concrete and so forth. In the future, this article's research will have an important meaning of the risk's assessment in the geological disaster.

The Application of Informatization Construction Technology in Karst Engineering

Yu Chunlei, Zhang Yabin, Wu Deming

2016, 30(6): 303-305,309. doi: 10.3969/j.issn.1007-2993.2016.06.009

[Abstract](34) [PDF 1738KB](5)

Abstract:
This paper expounds the importance of informatization construction technology in karst engineering, and it analyses the methods of application throughout engineering examples. We compare the reconnaissance data with the feedback information and data in every process of construction,in order to adjust the design and construction scheme timely, achieve the desired effect of karst governance,and save the construction cost.

The Design and Construction of the Permanence Trellis Retaining Wall

Jiang Haiyun

2016, 30(6): 306-309. doi: 10.3969/j.issn.1007-2993.2016.06.010

[Abstract](37) [PDF 7016KB](7)

Abstract:
At present, nailing walls, which have short service life, are usually used for foundation pit supporting and the temporary protection. If people make the soil nailing an intersection in the soil nail gun, they can set the beam and upstand like the lattice anchor rod retaining wall as well as the lattice soil nailing retaining wall. This paper introduces the method of calcu lating, the construction management and the requirements of construction of soil nailing used for permanent retaining wall through a practical project. It can be served as reference for the designers of such structures.

Study on Application of the Post Grouting Bored Pile in the Gravel Layer

Shi Zhongming

2016, 30(6): 310-312. doi: 10.3969/j.issn.1007-2993.2016.06.011

[Abstract](48) [PDF 701KB](9)

Abstract:
Bored pile construction will produce disturbance to the soil layeres which will reduce the pile side friction power and end friction power. Post grouting technology is used to improve the bearing capacity of pile and reduce settlement. According to an engineering example, the post grouting technology is indicated to be effective to improve the bearing capacity of a pile and reduce the cost. But understanding about the construction technology of the post grouting is needed to ensure the good results.

Application of the Dynamic Compaction Soil-cement Pile in Dealing with the High-rise Building's Foundation in the Collapsible Loess Region

Gong Fengwu

2016, 30(6): 313-316. doi: 10.3969/j.issn.1007-2993.2016.06.012

[Abstract](33) [PDF 539KB](10)

Abstract:
This paper introduces the characteristics of collapsible loess and its processing method, and emphatically introduces the concept of the compaction pile, development history and its applicable conditions. Mainly discussed lateral eompac tion pile contribution to ruination effects of loess collapsibility and chemical reaction of cement with water, soil contribution to the decisive role of reinforced composite foundation bearing capacity. By engineering example describes the design process and methods compacted soil-cement pile composite foundation construction process and ramming expanded dense cement soil pile and material requirements, quality control. This is the experience for reference of rammed cement-soil compaction pile further promoted in the same building in the same area.

Design and Construction Example of Variable Stiffness Leveling Foundation Treatment in Beijing Area

Zhou Junhong

2016, 30(6): 317-323. doi: 10.3969/j.issn.1007-2993.2016.06.013

[Abstract](29) [PDF 1356KB](8)

Abstract:
A project of Beijing design for multi tower structure with a large podium building group, there is big height difference among towers, and the core tube and frame column foundation of same tower bearing capacity difference of abnormal disparity, according to special requirements of the construction structure, by variable stiffness adjustment foundation treatment design of successful application, both greatly improve the natural foundation bearing capacity and reduce building subsidence and resolve differences in construction settlement is too large, but also to create a good economic and social benefits, also for engineering application in Beijing area with similar geological conditions of accumulated valuable experience.

2016 Vol. 30, No. 6