Test and Analysis on Reinforcement Effect of High Vacuum Compaction Method in Soft Soil

The dynamic compaction method is effective to reinforce soft soil foundation with a low degree of saturation. However, deep soft soil foundation with high degree of saturation has some different characteristics. It has been widely considered that dynamic compaction method is unsuitable to improve the characters of deep soft soil foundation with high degree of saturation. In this article, we will show that the dynamic compaction method with vacuum well-point dewatering is effective to deep soft soil foundation with high degree of saturation reinforcement. In situ and laboratorial experiments are used to assess the reinforcement effect of the deep soft soil foundation with high degree of saturation. Our results show that the dynamic compaction method causes long dissipation time of pore water pressure, and the dynamic compaction method with vacuum well-point dewatering makes construction time of a project 25% shorter. The effective depth of deep soft soil foundation with high degree of saturation reinforcement using the two experimental methods can reach to 8.0 m. In comparison with the total settlement and layered settlement of the dynamic compaction method with vacuum well-point dewatering, the dynamic compaction method settlement is relatively smaller. For soils with depth of 4 m, the reinforcement effect of dynamic compaction method with vacuum well-point dewatering is obviously superior to dynamic compaction method. Based on these results, we suggest construction procedures for different reinforcement depth of soils and construction time.

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Study on Vibro-Replacement Stone Pile Test for Soft Soil Foundation

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.543-547.3982 ◽

2014 ◽

Vol 543-547 ◽

pp. 3982-3985

Author(s):

Tie Liang Li ◽

Jing Meng ◽

Qiang Zhang ◽

Gan Zhang ◽

Lei Fei Deng ◽

...

Keyword(s):

Soft Soil ◽

Standard Penetration Test ◽

Reinforcement Effect ◽

Feeding Mode ◽

The Earth ◽

Feeding Type ◽

Before And After ◽

Undrained Strength ◽

Soil Foundation ◽

Soft Soil Foundation

This paper studies the applicability of vibro-replacement stone pile in combination of a port project in Dalian as well as heavy dynamic sounding and standard penetration test, studies the reinforcement effect of pile distance and feeding type on vibro-replacement stone and analyzes reinforcement effects of the side pile and the earth among piles. The results show: smaller pile distance will bring better pile compactness; for the vibro-replacement stone pile constructed in soft earth with undrained strength less than 20kPa with the conventional method, it is not easy to form compact pile; the reinforcement effect works only within 0.6m on the top; vibro-replacement stone pile with bottom feeding mode can form compact piles, but the pile has the interlayer which is not compact enough partially; the strength of the earth among piles fails to improve obviously before and after the stone pile is formed.

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Experiment Study on Reinforcement Effect of Composite Foundation in Saline Soils

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.622-623.1721 ◽

2012 ◽

Vol 622-623 ◽

pp. 1721-1724

Author(s):

Yu Zhang ◽

Jian Kun Liu ◽

Jian Hong Fang ◽

An Hua Xu

Keyword(s):

Design Theory ◽

Soft Soil ◽

Deformation Modulus ◽

Dynamic Compaction ◽

Engineering Practice ◽

Saline Soils ◽

Lake Area ◽

Reinforcement Effect ◽

Loading Test ◽

Short Period

Using DPT and plate loading test, the paper analyzed different reinforcement effects from four different reinforcement technologies－gravel piles method, dynamic compaction method, dynamic compaction replacement (DCR) method and impact compacted method for Cha-Ge highway saline soils ground located in salt lake area, and got the following conclusions: (1) DCR method has the best reinforcement effect, and impact compacted method has the worst. There is a difference of 166.9 % between them. (2)Tamping energy is important on reinforcement effect to the last three methods and related directly to the values of the strengthened bearing capacity and deformation modulus. The DCR method and gravel piles method mentioned above are useful on reducing the settlement of natural saline soils foundation. In recent years, a lot of ground treatment methods are widely used to consolidate soft soil foundation for its short period and simple construction and so on. Numerous scientists and engineers have obtained useful results and experience from DCR and gravel piles foundation treatment of soft soil [1,2,3,4]. (e.g., A. G. Phear, S. J. Harris, 2008; Dong,Yan and , 2009; Huang, Zhou and He, 2006; Liu, 2006;); But the reinforcement in regions of saline soils, such as DCR hasn't been well researched; theoretical study is far behind engineering practice; so it is hard to build up the design theory and method..

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High Vacuum Densification Method for Soft Soil Improvement

GeoCongress 2012 ◽

10.1061/9780784412121.198 ◽

2012 ◽

Author(s):

R. Y. Liang ◽

S. L. Xu

Keyword(s):

Soft Soil ◽

High Vacuum ◽

Soil Improvement

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Test Study on Effective Reinforcement Depth of Dynamic Compaction and Filling Replacement

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.368-373.2550 ◽

2011 ◽

Vol 368-373 ◽

pp. 2550-2553 ◽

Cited By ~ 1

Author(s):

Wei Li ◽

Chun Xiao Zhang ◽

Peng Xiang Sun

Keyword(s):

Bearing Capacity ◽

Low Cost ◽

Soft Soil ◽

Dynamic Compaction ◽

Reinforcement Effect ◽

Large Area ◽

Remarkable Effect ◽

Ground Treatment ◽

Test Study ◽

Effective Reinforcement

Filling replacement combined with dynamic compaction is a very effective method to preprocess the soft soil to obtain larger bearing capacity. That not only has remarkable effect to improve soil bearing capacity, but also has some advantages, such as quick construction, simple equipment, low cost and so on. And that is appropriate for large area ground treatment engineering. The purpose of ensuring the reinforcement effect and saving the project cost, and providing references for the similar projects can be achieved through the test study on effective reinforcement depth of dynamic compaction and filling replacement.

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INNOVATIVE SOFT SOIL IMPROVEMENT BY VACUUM DE-WATERING AND DYNAMIC COMPACTION

Proceedings of International Structural Engineering and Construction ◽

10.14455/isec.res.2016.43 ◽

2016 ◽

Vol 3 (1) ◽

Author(s):

Tuncer B. Edil

Keyword(s):

Large Scale ◽

Ground Improvement ◽

Soft Soil ◽

High Vacuum ◽

Cohesive Soil ◽

Soil Improvement ◽

Economic Benefits ◽

Dynamic Compaction ◽

Environmental Benefits ◽

Improvement Method

Recently, an innovative soft soil improvement method was advanced in China by integrating and modifying vacuum consolidation and dynamic compaction ground improvement techniques in an intelligent and controlled manner. This innovative soft soil improvement method is referred to as “High Vacuum Densification Method (HVDM)” to reflect its combined use of vacuum de-watering and dynamic compaction techniques in cycles. Over the past ten years, this innovative soft soil improvement technique has been successfully used in China and Asia for numerous large-scale soft soil improvement projects, from which enormous time and cost savings have been achieved. In this presentation, the working principles of the HVDM will be described. A discussion of the range of fine-grained, cohesive soil properties that would make them ideal for applying HVDM as an efficient ground improvement method will be discussed. The economic benefits and environmental benefits of HVDM are elucidated.

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The Application of Dynamic Compaction Techniques Combining Plastic Drainage Plate to Improve Soft Soil Foundations in a College

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.117-119.526 ◽

2011 ◽

Vol 117-119 ◽

pp. 526-530

Author(s):

Hai Yang Chen ◽

Xiu Jun Liu ◽

Jian Li ◽

Xing Hua Hou

Keyword(s):

Soft Soil ◽

Dynamic Compaction ◽

Geological Exploration ◽

Reinforced Plastic ◽

The Cost ◽

Compaction Method

After the research of detailed geological exploration report, as well as the selection and optimization of foundation processing programs, dynamic compaction method with reinforced plastic drainage board is chosen to achieve good results, shorten the duration and reduce the cost.

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Laboratory Tests and Numerical Analysis on the Grouting Reinforcement Effect for Soft-Soil Subgrade Settlement of High-Speed Railway

Ground Improvement and Geosynthetics ◽

10.1061/9780784413401.012 ◽

2014 ◽

Author(s):

Zhuohua Tang ◽

Qianwei Xu ◽

Xinan Yang ◽

Jun Zhang

Keyword(s):

Numerical Analysis ◽

High Speed ◽

Laboratory Tests ◽

Soft Soil ◽

Reinforcement Effect ◽

High Speed Railway ◽

Grouting Reinforcement

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Experimental Study on Dynamic Compaction-Plastics Drain Board Method in Backfill Subgrade Reinforcement

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.474-476.2032 ◽

2011 ◽

Vol 474-476 ◽

pp. 2032-2036

Author(s):

Yong Ma ◽

Mao Tian Luan ◽

Zhong Chang Wang

Keyword(s):

Experimental Study ◽

Pore Water ◽

Pore Water Pressure ◽

Water Pressure ◽

Soft Soil ◽

Time Effect ◽

Dynamic Compaction ◽

Excess Pore Water Pressure ◽

Compaction Method ◽

Excess Pore

Plastics drain board method is one of the most effective ways of reducing excess pore water pressure during the process of dynamic compaction in soft soil subgrade reinforcement. Based on field test in neritic backfilled area of Jinzhou Port 207B berth, the pore water pressure, groundwater level, subgrade bearing capacity and time effect of deformation have been measured and analyzed. The application of dynamic compaction-PDB method makes a mighty advance of the dynamic compaction method, which provides a new way for soft soil treatment in coastal areas.

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