Full Text:   <1399>

Summary:  <1401>

CLC number: TU447

On-line Access: 2021-02-05

Received: 2020-04-01

Revision Accepted: 2020-07-06

Crosschecked: 2021-01-14

Cited: 0

Clicked: 2027

Citations:  Bibtex RefMan EndNote GB/T7714

 ORCID:

Jing-jin Liu

https://orcid.org/0000-0001-8641-0438

-   Go to

Article info.
Open peer comments

Journal of Zhejiang University SCIENCE A 2021 Vol.22 No.2 P.147-164

http://doi.org/10.1631/jzus.A2000133


Consolidation behavior of Tianjin dredged clay using two air-booster vacuum preloading methods


Author(s):  Hua-yang Lei, Yao Hu, Jing-jin Liu, Xu Liu, Chen-yuan Li

Affiliation(s):  Department of Civil Engineering, Tianjin University, Tianjin 300350, China; more

Corresponding email(s):   liujingjinljj@163.com

Key Words:  Tianjin dredged clay, Prefabricated vertical drain air-booster vacuum preloading (PAVP), Tube air-booster vacuum preloading (TAVP), Model test, Microstructure test


Share this article to: More <<< Previous Article|

Hua-yang Lei, Yao Hu, Jing-jin Liu, Xu Liu, Chen-yuan Li. Consolidation behavior of Tianjin dredged clay using two air-booster vacuum preloading methods[J]. Journal of Zhejiang University Science A, 2021, 22(2): 147-164.

@article{title="Consolidation behavior of Tianjin dredged clay using two air-booster vacuum preloading methods",
author="Hua-yang Lei, Yao Hu, Jing-jin Liu, Xu Liu, Chen-yuan Li",
journal="Journal of Zhejiang University Science A",
volume="22",
number="2",
pages="147-164",
year="2021",
publisher="Zhejiang University Press & Springer",
doi="10.1631/jzus.A2000133"
}

%0 Journal Article
%T Consolidation behavior of Tianjin dredged clay using two air-booster vacuum preloading methods
%A Hua-yang Lei
%A Yao Hu
%A Jing-jin Liu
%A Xu Liu
%A Chen-yuan Li
%J Journal of Zhejiang University SCIENCE A
%V 22
%N 2
%P 147-164
%@ 1673-565X
%D 2021
%I Zhejiang University Press & Springer
%DOI 10.1631/jzus.A2000133

TY - JOUR
T1 - Consolidation behavior of Tianjin dredged clay using two air-booster vacuum preloading methods
A1 - Hua-yang Lei
A1 - Yao Hu
A1 - Jing-jin Liu
A1 - Xu Liu
A1 - Chen-yuan Li
J0 - Journal of Zhejiang University Science A
VL - 22
IS - 2
SP - 147
EP - 164
%@ 1673-565X
Y1 - 2021
PB - Zhejiang University Press & Springer
ER -
DOI - 10.1631/jzus.A2000133


Abstract: 
This paper presents model tests (macro aspect) and microstructure tests (micro aspect) for investigating the consolidation behavior of tianjin dredged clay using the prefabricated vertical drain air-booster vacuum preloading (PAVP) and tube air-booster vacuum preloading (TAVP) methods. The mechanism of air-booster vacuum preloading (AVP) using a spring-like system is explained. The main difference between these two methods is the air-boosting equipment. A new anticlogging air-booster prefabricated vertical drain (PVD) is used in the PAVP technique and a self-designed air-booster tube is used in the TAVP technique. In the model tests, a comparison of the variables that are monitored during reinforcement (vacuum pressure, surface settlement, water discharge, and pore-water pressure) and after reinforcement (water content, dry density, and vane shear strength) is conducted. The results indicate that the consolidation behavior of tianjin dredged clay using the PAVP method is better than that using the TAVP method. PAVP more efficiently mitigates the issue of water-draining PVD clogging and significantly accelerates drainage consolidation. In addition, in the microstructure tests, a comparison of the variables that are monitored after reinforcement (via scanning electron microscopy (SEM) and mercury intrusion porosimetry (MIP)) is conducted, and the results further explain the model test results.

两种增压式真空预压加固天津吹填粘土试验研究

目的:增压式真空预压是加固吹填软土的有效方法,目前主要有排水板注气和增压管注气两种.本文旨在对比分析两种方式的加固效果(真空度、排水量、固结度、剪切强度和微观结构特征等),选出最优加固方法,以期指导工程实践.
创新点:1. 通过模型试验,从宏观角度对比评估两种增压式真空预压的加固效果;2. 通过微观结构试验,从微观角度进一步评估加固效果;3. 分析排水板-增压式真空预压加固效果优于注气管-增压式真空预压的原因.
方法:1. 通过模型试验分析,对比分析两种方法的加固效果(真空度、排水量、固结度、剪切强度和微观结构特征等);2. 通过微观结构试验(扫描电镜和压汞)分析,验证模型试验的结果,并进一步对比排水板-增压式真空预压和注气管-增压式真空预压的加固效果.
结论:1. 在模型试验中,相对于注气管-增压式真空预压,排水板-增压式真空预压的排水量、固结沉降和孔压消散更大,而含水量、剪切强度和固结度更小;2. 在微观结构试验中,排水板-增压式真空预压加固后的土体骨架颗粒形态更均匀密实,孔隙更小;3. 排水板-增压式真空预压的加固效果优于注气管-增压式真空预压.

关键词:天津吹填粘土;排水板-增压式真空预压;注气管-增压式真空预压;模型试验;微观试验

Darkslateblue:Affiliate; Royal Blue:Author; Turquoise:Article

Reference

[1]Arasan S, Akbulut S, Hasiloglu AS, 2011. The relationship between the fractal dimension and shape properties of particles. KSCE Journal of Civil Engineering, 15(7):1219-1225.

[2]Azari B, Fatahi B, Khabbaz H, 2016. Assessment of the elastic-viscoplastic behavior of soft soils improved with vertical drains capturing reduced shear strength of a disturbed zone. International Journal of Geomechanics, 16(1):B4014001.

[3]Bergado DT, Balasubramaniam AS, Fannin RJ, et al., 2002. Prefabricated vertical drains (PVDs) in soft Bangkok clay: a case study of the new Bangkok International Airport project. Canadian Geotechnical Journal, 39(2):304-315.

[4]Cai YQ, Qiao HH, Wang J, et al., 2017. Experimental tests on effect of deformed prefabricated vertical drains in dredged soil on consolidation via vacuum preloading. Engineering Geology, 222:10-19.

[5]Cai YQ, Xie ZW, Wang J, et al., 2018. New approach of vacuum preloading with booster prefabricated vertical drains (PVDs) to improve deep marine clay strata. Canadian Geotechnical Journal, 55(10):1359-1371.

[6]Chai JC, Miura N, Nomura T, 2004. Effect of hydraulic radius on long-term drainage capacity of geosynthetics drains. Geotextiles and Geomembranes, 22(1-2):3-16.

[7]Chai JC, Hayashi S, Carter JP, 2006. Vacuum consolidation and its combination with embankment loading. GeoShanghai International Conference, p.177-184.

[8]Chu J, Yan SW, 2015. Application of the vacuum preloading method in soil improvement projects. Elsevier Geo-Engineering Book Series, 3:91-117.

[9]Chu J, Yan SW, Yang H, 2000. Soil improvement by the vacuum preloading method for an oil storage station. Géotechnique, 50(6):625-632.

[10]Delage P, Lefebvre G, 1984. Study of the structure of a sensitive Champlain clay and of its evolution during consolidation. Canadian Geotechnical Journal, 21(1):21-35.

[11]Hyslip JP, Vallejo LE, 1997. Fractal analysis of the roughness and size distribution of granular materials. Engineering Geology, 48(3-4):231-244.

[12]Indraratna B, Sathananthan I, Rujikiatkamjorn C, et al., 2005. Analytical and numerical modeling of soft soil stabilized by prefabricated vertical drains incorporating vacuum preloading. International Journal of Geomechanics, 5(2):114-124.

[13]Indraratna B, Rujikiatkamjorn C, Balasubramaniam AS, 2014. Consolidation of estuarine marine clays for coastal reclamation using vacuum and surcharge loading. Geo-Congress, p.358-369.

[14]Inyang HI, Bae S, Mbamalu G, et al., 2007. Aqueous polymer effects on volumetric swelling of Na-montmorillonite. Journal of Materials in Civil Engineering, 19(1):84-90.

[15]Katsman R, Ostrovsky I, Makovsky Y, 2013. Methane bubble growth in fine-grained muddy aquatic sediment: insight from modeling. Earth and Planetary Science Letters, 377-378:336-346.

[16]Lei HY, Qi ZY, Zhang ZP, et al., 2017a. New vacuum-preloading technique for ultrasoft-soil foundations using model tests. International Journal of Geomechanics, 17(9):04017049.

[17]Lei HY, Li X, Wang L, et al., 2017b. Reinforcement effect of polyacrylamide on dredger fill improved by vacuum preloading. Proceedings of the International Conference on Transportation Infrastructure and Materials.

[18]Lei HY, Hu Y, Zheng G, et al., 2020. Improved air-booster vacuum preloading method for newly dredged fills: laboratory model study. Marine Georesources & Geotechnology, 38(4):493-510.

[19]Li LH, Wang Q, Wang NX, et al., 2009. Vacuum dewatering and horizontal drainage blankets: a method for layered soil reclamation. Bulletin of Engineering Geology and the Environment, 68(2):277-285.

[20]Liu JJ, Lei HY, Zheng G, et al., 2017. Laboratory model study of newly deposited dredger fills using improved multiple-vacuum preloading technique. Journal of Rock Mechanics and Geotechnical Engineering, 9(5):924-935.

[21]Liu JJ, Lei HY, Zheng G, et al., 2018. Improved synchronous and alternate vacuum preloading method for newly dredged fills: laboratory model study. International Journal of Geomechanics, 18(8):04018086.

[22]Ong CY, Chai JC, 2011. Lateral displacement of soft ground under vacuum pressure and surcharge load. Frontiers of Architecture and Civil Engineering in China, 5(2):239.

[23]Shen YP, Wang HH, Tian YH, et al., 2015. A new approach to improve soft ground in a railway station applying air-boosted vacuum preloading. Geotechnical Testing Journal, 38(4):373-386.

[24]Wang J, Cai YQ, Ma JJ, et al., 2016. Improved vacuum preloading method for consolidation of dredged clay-slurry fill. Journal of Geotechnical and Geoenvironmental Engineering, 142(11):06016012.

[25]Wang J, Ni JF, Cai YQ, et al., 2017. Combination of vacuum preloading and lime treatment for improvement of dredged fill. Engineering Geology, 227:149-158.

[26]Wang J, Zhao R, Cai YQ, et al., 2018. Vacuum preloading and electro-osmosis consolidation of dredged slurry pre-treated with flocculants. Engineering Geology, 246:123-130.

[27]Wang J, Huang G, Fu HT, et al., 2019. Vacuum preloading combined with multiple-flocculant treatment for dredged fill improvement. Engineering Geology, 259:105194.

[28]Yan SW, Chu J, 2005. Soil improvement for a storage yard using the combined vacuum and fill preloading method. Canadian Geotechnical Journal, 42(4):1094-1104.

[29]Ye T, 2018. Experimental Observation and Theoretical Analysis on the Bubbles’ Shape within Transparent Soft Soil. MS Thesis, Zhejiang University, Hangzhou, China (in Chinese).

[30]Yu C, Wang H, Zhou AN, et al., 2019. Experimental study on strength and microstructure of cemented soil with different suctions. Journal of Materials in Civil Engineering, 31(6):04019082.

[31]Zhang T, Cai GJ, Liu SY, 2018a. Application of lignin-stabilized silty soil in highway subgrade: a macroscale laboratory study. Journal of Materials in Civil Engineering, 30(4):04018034.

[32]Zhang T, Cai GJ, Liu SY, 2018b. Reclaimed lignin-stabilized silty soil: undrained shear strength, Atterberg limits, and microstructure characteristics. Journal of Materials in Civil Engineering, 30(11):04018277.

[33]Zheng G, Liu JJ, Lei HY, et al., 2017. Improvement of very soft ground by a high-efficiency vacuum preloading method: a case study. Marine Georesources & Geotechnology, 35(5):631-642.

Open peer comments: Debate/Discuss/Question/Opinion

<1>

Please provide your name, email address and a comment





Journal of Zhejiang University-SCIENCE, 38 Zheda Road, Hangzhou 310027, China
Tel: +86-571-87952783; E-mail: cjzhang@zju.edu.cn
Copyright © 2000 - 2022 Journal of Zhejiang University-SCIENCE