Studies on the Residual Settlement of CFG Pile Composite Foundation of the Wuhan-Guangzhou High Speed Railway

2012 ◽  
Vol 178-181 ◽  
pp. 1590-1595
Author(s):  
Feng Zhang ◽  
Zhao Yi Xu ◽  
Zhi Yi Li
Keyword(s):  
High Speed ◽  
Soil Layer ◽  
Composite Foundation ◽  
High Speed Railway ◽  
Actual Observation ◽  
Permanent Load ◽  
Cfg Pile Composite Foundation ◽  
Gravel Pile ◽  
Pile Length ◽  
Cfg Pile

Wuhan-Guangzhou passenger special line is the most important backbone of China high speed railway net. The line span is 968 km, among of them; roadbed is 388 km, occupied 40.1% of the total line. Due to the rigorous residual settlement of the roadbed, the CFG (Cement Flayash Gravel) pile is used as the composite foundation to enforce the intensity of roadbed and reduce the post-settlement. The paper studies on CFG pile composite foundation at the Wuhan experimental section, using the finite element numerical simulate the interaction of the pile and pile surrounding soil under the permanent load conditions. The results show that the stimulation model has the more accordance with the actual observation results. The residual settlement comes from the soil layer is bigger than the pile length.

Composite Foundation on Bearing Characteristics and Simulation Analysis CFG Pile for the High Speed Railway

2011 ◽  
Vol 71-78 ◽  
pp. 3827-3831
Author(s):  
A Lan Jiang ◽  
Mei Xia Wang
Keyword(s):  
High Speed ◽  
Simulation Analysis ◽  
Coupling Effect ◽  
Rapid Development ◽  
Composite Foundation ◽  
Treatment Technology ◽  
High Speed Railway ◽  
Cfg Pile Composite Foundation ◽  
Sand And Gravel ◽  
Cfg Pile

With the rapid development of high-speed railway in soft foundation, foundation treatment technology has become mature, the most outstanding is CFG pile composite foundation technique. CFG pile composite foundation is made of cement fly ash gravel pile(CFG pile), pile of soil and sandstone , between sand and gravel several problems such as the medium material composition together constitute layer. It has high bearing of capacity, convenient, low costing, strong adaptability and quality control easier.So it is widely applied and promoted. Under static and dynamic loads, the relations of the high-speed railway CFG pile composite foundation is very complex. In order to further understand the intensity of pile-net structure subgrade stability and deformation, pile , requirements of the high-speed railway roadbed ,it needs to do pile-net structure parameter sensitivity analysis. According to high-speed railway CFG pile composite foundation , the numerical analysis can well solve the coupling effect of piles and soil. So, this paper adopts FLAC3D finite difference software is simulated and analyzed.

Research on Stress Distribution of CFG Pile-Net Composite Foundation in High-Speed Railway

2013 ◽  
Vol 361-363 ◽  
pp. 1833-1837 ◽  
Author(s):  
Jun Cheng ◽  
Ji Wen Zhang
Keyword(s):  
Numerical Simulation ◽  
High Speed ◽  
Stress Ratio ◽  
Field Tests ◽  
Composite Foundation ◽  
Additional Stress ◽  
High Speed Railway ◽  
Soil Stress ◽  
Gravel Pile ◽  
Cfg Pile

Combined with the field tests of CFG (Cement Fly-ash Gravel) pile-net (geogrid) composite foundation in Danyang Test Section of the Beijing-Shanghai High-speed Railway, the settlement, pile-soil stress ratio and additional stress of composite foundation were analyzed by numerical simulation. It shows that the pile-soil stress ratio of CFG pile-net composite foundation is in the range of 4 to 6. And the reasonable distribution of additional stress in composite foundation is also discussed. The results can provide references for the design of the CFG pile-net composite foundation under embankment in high-speed railway.

The Settlement Analysis of the Cement Fly-Ash Gravel Pile Composite Foundation of Baotou

2014 ◽  
Vol 580-583 ◽  
pp. 518-523
Author(s):  
Juan Li ◽  
Yao Xu ◽  
Jun Yin
Keyword(s):  
Fly Ash ◽  
Composite Foundation ◽  
Settlement Calculation ◽  
Practical Engineering ◽  
Cfg Pile Composite Foundation ◽  
Modified Formula ◽  
Gravel Pile ◽  
Final Settlement ◽  
Settlement Analysis ◽  
Cfg Pile

This paper analyzes the causes of larger differences of final settlement calculated value of cement fly-ash gravel pile (CFG pile) composite foundation of Baotou with actual observed result of it. On the basis of analysis on a number of practical engineering data of Baotou, we modify the settlement formula of the CFG pile composite foundation and gain the modified coefficient applied to the settlement calculation of the CFG pile composite foundation of Baotou. The modified formula and coefficient proposed in this paper have a positive effect on the accurate settlement calculation of puting forward a more accurate correction formula and coefficient of the calculation of the CFG pile composite foundation of Baotou.

scholarly journals Research on character of screw pile group composite foundation used in high-speed railway

2019 ◽  
Vol 265 ◽  
pp. 05010
Author(s):  
Maocai Zhao ◽  
Lu Zhang
Keyword(s):  
High Speed ◽  
Rapid Development ◽  
Pile Group ◽  
Element Model ◽  
Composite Foundation ◽  
Design Parameters ◽  
High Speed Railway ◽  
Screw Pile ◽  
Side Resistance ◽  
Pile Length

As a result of rapid development of a high-speed railway and infrastructure in China in recent years, the subgrade deformation and settlement control standards put forward more stringent requirements. Based on ABAQUS 6.14, established finite element model of screw pile group composite foundation. Then obtained the settlement, axial force distribution and pile side resistance distribution of center pile of pile group. Next design parameters sensitive analysis was made, such as pile length, pile spacing and so on, in order to obtain a reasonable design pile parameters by analysis of mechanical behavior.

Application of LS-SVM to Prediction of Bearing Capacity of Cement-Flyash-Gravel Pile Composite Foundation

2013 ◽  
Vol 438-439 ◽  
pp. 1399-1403
Author(s):  
Wei Ding ◽  
Qing Liu ◽  
Kang Kang Sun ◽  
Feng Tao Sui
Keyword(s):  
Bearing Capacity ◽  
Great Influence ◽  
Composite Foundation ◽  
Learning Ability ◽  
Support Vector ◽  
Data Prediction ◽  
Svm Model ◽  
Cfg Pile Composite Foundation ◽  
Gravel Pile ◽  
Cfg Pile

There are a lot of factors that influence the bearing capacity of composite foundation, and the relationship between them is complex and nonlinear. Based on study of main factors that have great influence on bearing capacity of cement-flyash-gravel (CFG) pile composite foundation, the least squares support vector machine (LS-SVM) model of bearing capacity of composite foundation was established. The results show that the model has excellent learning ability and generalization and can provide accurate data prediction only with fewer observed sample. It is proved that the new method is a promising method for the determination of bearing capacity of CFG pile and other rigid piles composite foundation.

The Effect of CFG-Pile Caps and Cushion to Stability of Embankment

2011 ◽  
Vol 287-290 ◽  
pp. 797-800
Author(s):  
Zhen Hua Wu ◽  
Jian Yi Yuan
Keyword(s):  
High Speed ◽  
Stress Ratio ◽  
Dynamic Stress ◽  
Vertical Section ◽  
Composite Foundation ◽  
High Speed Railway ◽  
Dynamic Displacement ◽  
Wide Range ◽  
Pile Caps ◽  
Cfg Pile

Subgrade diseases are exposed more and more serious with raising speed of existing railway in wide range. Dynamic numerical simulation had been done to analyze the effect of CFG-pile caps and cushion in composite foundation with CFG-pile in low embankment of Beijing-Shanghai high-speed railway. Distribution rules of dynamic displacement and dynamic stress of the subgrade surface and ground surface on the cross section, attenuation rules of dynamic response and dynamic stress ratio between pile and soil on the vertical section were studied. It shows that the dynamic stress of pile and soil generally attenuates in depth and attenuation of dynamic stress ratio between pile and soil mostly concentrates in the scope of 10m beneath the ground and dynamic stress caused by train load is undertaken by the pile. Moreover the scheme of CFG-pile with no pile caps and rigid cushion scheme is superior to that of pile caps and flexible cushion scheme for enhancing dynamic stability and reducing dynamic displacement and stress in low embankment. It will be instructive to control design and construction for the low embankment in Beijing-Shanghai high-speed railway.

Numerical Simulation on the Reinforcing Effect of New CFG Pile-Board Structure Composite Foundation

2011 ◽  
Vol 243-249 ◽  
pp. 2415-2418
Author(s):  
Ding Bang Zhang
Keyword(s):  
Numerical Simulation ◽  
High Speed ◽  
Composite Foundation ◽  
Board Structure ◽  
Treatment Technique ◽  
High Speed Railway ◽  
Concrete Pile ◽  
Soil Stress ◽  
Deformation Compatibility ◽  
Cfg Pile

The new CFG pile-board structure composite foundation is a ground treatment technique based on CFG pile foundation and pile-board structure composite foundation. It can make full use of the load distributing function of board, the bearing capacity and the deformation compatibility of soil between piles, by taking advantage of the pile-platform-soil interaction. A part of soft ground in a high-speed railway was taken as the engineering background and study object. The settlement controlling effect of common CFG pile ground and new CFG pile-board structure composite foundation were analyzed by finite element numerical method, and various factors to the effect on settlement-controlling were discussed. Pile-soil stress ratio of CFG pile and reinforced concrete pile were studied. Some useful conclusions of the numerical simulation of the new CFG pile-board structure composite foundation were obtained.

Sign in / Sign up

Export Citation Format

Share Document