Earth fissures developed within collapsible loess area caused by groundwater uplift in Weihe watershed, northwestern China

2019 ◽  
Vol 173 ◽  
pp. 364-373 ◽  
Author(s):  
Mingdong Zang ◽  
Jianbing Peng ◽  
Shengwen Qi
Keyword(s):  
Northwestern China ◽  
Loess Area ◽  
Earth Fissures ◽  
Collapsible Loess

Application Research of Compaction Pile in Heavy Collapsible Loess

2011 ◽  
Vol 90-93 ◽  
pp. 1390-1393 ◽  
Author(s):  
Yong Qiang He ◽  
Yan Peng Zhu ◽  
Yun Wu ◽  
Xiao Qing Wang
Keyword(s):  
Soil Compaction ◽  
Composite Foundation ◽  
Application Research ◽  
Loess Area ◽  
Foundation Treatment ◽  
Collapsible Loess ◽  
Expansion Theory ◽  
Soil Compressibility ◽  
Cavity Expansion Theory ◽  
Physical Mechanics

Compaction piles is one of the conventional methods for foundation treatment in collapsible loess, there are very few research results about soil compaction effect between piles when forming the piles. Firstly, the stress field and displacement field of soil around compaction piles are elastic-plastic analyzed on the basis of the cavity expansion theory; then a series of field and laboratory tests were performed to evaluate the treatment effect of the compaction pile composite foundation. The result shows that the collapsibility has been eliminated, all physical mechanics indexes have been improved, and soil compressibility and modulus of compressibility are also increased remarkably. It embodies the correctness of the computation theory. And the feasibility of the compaction piles composite foundation on collapsible loess area is further proved.

scholarly journals Analysis of Vertical Load Transfer Mechanism of Assembled Lattice Diaphragm Wall in Collapsible Loess Area

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Mingtan Xia ◽  
Xudong Zhang ◽  
Gengshe Yang ◽  
Liu Hui ◽  
Wanjun Ye
Keyword(s):  
Failure Modes ◽  
Load Transfer ◽  
Diaphragm Wall ◽  
Vertical Load ◽  
Soil System ◽  
Loess Area ◽  
Collapsible Loess ◽  
Negative Friction ◽  
Vertical Bearing ◽  
Soil Interface

Based on analysis of the formation mechanism and characteristics of the negative friction in collapsible loess areas, this study investigates the load transfer law of a wall-soil system under a vertical load, establishes the vertical bearing model of a lattice diaphragm wall, and analyzes the vertical bearing capacity of an assembled latticed diaphragm wall (ALDW) in a loess area. The factors influencing the vertical bearing characteristics of the ALDW in a loess area are analyzed. The vertical bearing mechanism of the lattice diaphragm wall in the loess area is investigated. The failure modes of the ALDW in the loess area are mainly shear failure of the soil around the wall and failure of the wall-soil interface. In the generation and development of negative friction, there is always a point where the relative displacement of the wall-soil interface is zero at a certain depth below the ground; at this point, the wall and soil are relative to each other. The collapsibility of loess, settlement of the wall and surrounding soil, and rate and method of immersion are the factors affecting the lattice diaphragm wall. The conclusions of this study provide a reference for the design and construction of ALDWs in loess areas.

Analysis of Foundation Non-Uniform Settlement for Building on Collapsible Loess

2013 ◽  
Vol 353-356 ◽  
pp. 213-216 ◽  
Author(s):  
Yuan Xun Li ◽  
Yan Peng Zhu ◽  
Shuai Hua Ye ◽  
Zhong Mao He
Keyword(s):  
Water Level ◽  
Underground Water ◽  
Frost Heaving ◽  
Loess Area ◽  
Adjacent Buildings ◽  
Project Analysis ◽  
Collapsible Loess ◽  
Underground Water Level

The primary causes of non-uniform settlement for buildings on collapsible loess are large settlement of subsoil, local subsidence foundation, frost heaving of ground, infusion foundation, underground water level decrease and the influence of adjacent buildings and so on. According to the characteristics of the project, analysis the reasons of building that non-uniform settlement and fissure on the wall. Combine the method of reinforce the rectification for original building, put forward the method of reinforce the rectification which is applicable to the project. And put forward some suggestions for collapsible loess area construction, for the colleague reference.

scholarly journals Study on Foundation Treatment Technology of Comprehensive Pipe Gallery in Collapsible Loess Area

2020 ◽  
Vol 560 ◽  
pp. 012046
Author(s):  
Liangcheng Li ◽  
Qi Liu ◽  
Jianxun Ma ◽  
Rubin Jia ◽  
Wenyan Zhou ◽  
...  
Keyword(s):  
Treatment Technology ◽  
Loess Area ◽  
Foundation Treatment ◽  
Collapsible Loess

scholarly journals Research on the Collapse Coefficient of Collapsible Loess under Unloading

2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Bin Zhi ◽  
Pingping Wei ◽  
Xiaochan Wang ◽  
Zengyue Li ◽  
Yilong Ren ◽  
...  
Keyword(s):  
Field Test ◽  
Stress Ratio ◽  
Underground Space ◽  
Function Form ◽  
Loess Area ◽  
Collapsible Loess ◽  
Space Projects ◽  
Collapse Ratio

In the geogenetic overburden excavation of underground space projects (such as comprehensive pipe corridors or subways), the foundation stress is in an unloading state. The effect(s) from the unloading on the coefficient of subsidence in the loess area should be considered. In this study, to explore the effect of unloading on the collapsibility of loess, the collapsible loess in the Guanzhong area was considered as the research object. An expression for the unloading collapse coefficient was established based on the unloading stress ratio, unloading collapse ratio, and other parameters. The influence of the unloading on the loess collapse coefficient was studied using an indoor collapsibility test, and the function form and parameters for the expression were determined. As combined with the field test, the accuracy of the expression for the unloading coefficient was verified based on the test value for the specific collapsibility, calculated value for the specific collapsibility, and calculated value for the unloading collapsibility.

Comparative Study on Settlement Prediction of Railway Subgrade on Collapsible Loess Area

2012 ◽  
Vol 188 ◽  
pp. 49-53
Author(s):  
Xue Ning Ma ◽  
Xu Wang
Keyword(s):  
Exponential Model ◽  
Hyperbolic Model ◽  
Settlement Prediction ◽  
Loess Area ◽  
Railway Line ◽  
Collapsible Loess ◽  
Practical Engineering ◽  
Loess Region ◽  
Term Monitoring

The settlement prediction is an important problem to railway subgrade design and construction in the collapsible loess region. Prediction of subgrade settlement is more methods through measured data in practical engineering. Based on the long-term monitoring data of settlement of loess subgrade at Lanzhou-Wuwei second-railway line, a new prediction model was put up and contrasted with other models such as Hyperbolic model, Logarithm model, exponential model and Poisson’s model. The results showed that the new model could be better predict settlement laws of loess subgrade, and agreed well with hyperbolic model forecast results, and proved the correctness of the model.

Research on FLAC 3D Numerical Simulation of Working Mechanism of Compaction Pile Composite Foundation

2012 ◽  
Vol 204-208 ◽  
pp. 220-223
Author(s):  
Yong Qiang He ◽  
Hui Qing Zhang ◽  
Bin Can Liu ◽  
Yun Wu
Keyword(s):  
Soil Compaction ◽  
Composite Foundation ◽  
Working Mechanism ◽  
3D Numerical Simulation ◽  
Loess Area ◽  
Foundation Treatment ◽  
Collapsible Loess ◽  
Expansion Theory ◽  
Flac 3D ◽  
Cavity Expansion Theory

Compaction piles is one of the conventional methods for foundation treatment in collapsible loess, there are very few research results about soil compaction effect between piles when forming the piles. Firstly, the stress field and displacement field of soil around compaction piles are elastic-plastic analyzed on the basis of the cavity expansion theory; then a series of FLAC 3D numerical simulations were performed to evaluate the treatment effect of the compaction pile composite foundation. The result shows that all bearing capacity has improved, and quicklime compaction pile composite foundation has been increased remarkably. It embodies the correctness of the computation theory. And the feasibility of the compaction piles composite foundation on collapsible loess area is further proved.

scholarly journals Application of Controllable Splitting Grouting Technology in Loess Foundation Reinforcement

2021 ◽  
Vol 2101 (1) ◽  
pp. 012025
Author(s):  
Qingang Liu ◽  
Mingru Zhou ◽  
Lin Zhong ◽  
Shaofei Li ◽  
Yiming Chen
Keyword(s):  
Bearing Capacity ◽  
Foundation Settlement ◽  
Loess Area ◽  
Grouting Pressure ◽  
Collapsible Loess ◽  
Pressure Grouting ◽  
Jack Up ◽  
Heating Boiler ◽  
Large Heating

Abstract Taking the foundation settlement accident of a large heating boiler foundation in a city in collapsible loess area as an example, controllable splitting grouting can be achieved by controlling the grouting pressure, grouting pipe opening form, grouting volume and grouting method etc., so as to stabilize foundation settlement and improve foundation bearing capacity, for the boiler with large uneven settlement, for boilers with large uneven settlement, quicklime piles are used to jack up the foundation after splitting grouting to stabilize the foundation, the foundation is lifted with quicklime piles after splitting grouting to stabilize the foundation. The results show that the grouting amount of soil is within the design range, the grout splits in the soil several times to form a slurry vein, the settlement is stable after boiler reinforcement, the quicklime method can jack up the foundation and reduce the uneven settlement of the foundation, and the use of controllable splitting grouting can basically eliminate the slight collapsibility grade loess, which provides a new idea for solving the similar problem of uneven settlement of collapsible loess foundation buildings.

Sign in / Sign up

Export Citation Format

Share Document