Dynamic replacement,as a treatment method for soft soil foundation,has some shortcomings such as the gap between the replacement columns and the basement,large post-construction settlement,and low construction efficiency. In view of this,a dynamic replacement method with prebored filling is proposed to enhance the bearing capacity of foundation and reduce the post-construction settlement by tamping the prebored columns filled with materials under high energy level. The method is verified feasible through plate loading test,heavy dynamic penetration test and water filling and preloading test after tamping,and finally successfully applied to the whole soft soil foundation site. The number of dynamic sounding blows after tamping increased by over 260%,the bearing capacity of composite foundation reached 280 kPa,and the maximum settlement of tank foundation and the settlement difference of adjacent measuring points are far less than the requirements of specification. The successful application of this method serves as reference for the treatment of similar foundation.
Key words
soft soil foundation /
dynamic replacement method /
dynamic compaction with high energy level /
prebored /
water filling and preloading test /
post construction settlement
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References
[1] JGJ 79—2012,建筑地基处理技术规范[S].北京:中国建筑工业出版社,2012.
[2] 水伟厚.对强夯置换概念的探讨和置换墩长度的实测研究[J].岩土力学,2011,32(增刊2):502-506.
[3] 宜庐峻,付 桂.海工重载场地软土地基加固设计与现场试验[J].水运工程,2020(11):155-160.
[4] 徐玉胜.大能量强夯置换法处理深圳地区软土地基的应用研究[D].北京:中国铁道科学研究院,2009.
[5] 马永峰.不同能级强夯置换处理软土地基现场试验[J].中国海洋大学学报(自然科学版),2018,48(7):111-122.
[6] 郑凌逶,周风华,谢新宇.强夯置换中碎石运动机制和成墩过程的数值模拟[J].岩土工程学报(自然科学版),2013,35(11):2068-2075.
[7] 付 浩,于开宁,赵 健,等.不同施工参数下海漫滩回填地基强夯及强夯置换对比试验研究 [J].施工技术,2017,46(19):49-54.
[8] 陈国栋.分层强夯置换在大型油罐地基处理中的应用[J].建筑结构,2017,47(6):96-101.
[9] 郑凌逶.强夯置换软土中碎石墩形成过程的试验研究[J].岩土力学,2014,35(1):90-97.
[10] 王铁宏.高能级强夯技术发展研究与工程应用[M].北京:中国建筑工业出版社,2017.
[11] 王铁宏,水伟厚,王亚凌,等.强夯法有效加固深度的确定方法与判定标准[J].工程建设标准化,2005(3):27-38.
[12] 詹金林,水伟厚,何利军,等.18000 kN.m能级强夯处理深厚填海碎石土试验[J].工业建筑,2010,40(4):96-99.
[13] 中化岩土工程股份有限公司.预成孔填料置换平锤强夯法专利:中国,2015101370087[P].2016-10-26.
[14] 水伟厚.高能级强夯地基土载荷试验研究[J].岩土工程学报,2007,29(7):1090-1093.
[15] GB 50473—2008,钢制储罐地基基础设计规范[S].北京:中国计划出版社,2009.