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| Performance features of composite foundation of top-shaped concrete blocks-sand bag well without connecting bars |
| LIU Guangyu1，YU Yanjie2，3，LI Guowei2，4，XIONG Li2，5，WU Jiantao2，4 |
| (1. Erguang Branch of Guangdong Road and Bridge Construction Development Co.，Ltd.，Qingyuan，Guangdong 513300，China；2. Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering，Hohai University，Nanjing，Jiangsu 210024，China；3. Zhejiang Electric Power Construction Company，Ningbo，Zhejiang 315000，China；4. Highway and Railway Research Institute，Hohai University，Nanjing，Jiangsu 210024，China；5. Geotechnical Research Institute，Hohai University，Nanjing，Jiangsu 210024，China) |
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Abstract The composite foundation of top-shaped concrete blocks(TSCB)-sand bag well(SBW) were found to perform very well in soft clayey deposit treatment. However，relevant study about the optimum design of TSCB-SBW foundation were seldom reported. This research compared the engineering performance normal TSCB-SBW foundation and the non-connecting bar(NCB) TSCB-SBW foundation to investigate the features and functions of connecting bars in the TSCB-SBW system. The results showed that (1) the NCB TSCB-SBW foundation has only 10% higher settlement and 20% larger lateral displacement than the normal TSCB-SBW foundation. In addition，the NCB TSCB-SBW foundation showed a better mechanical performance and an equivalent plastic strain with normal TSCB-SBW foundation. (2) Compared with the gravel cushion，as the excellent self-balance of TSCB，TSCB-SBW foundation behaves good integrity and deformation controlling. In general，NCB TSCB-SBW foundation and normal TSCB-SBW foundation presented similarity in settling controlling，pore pressure dissipation，stress in blocks and distribution of plastic strain.
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2021, Vol. 40 
