十字板强度在确定真空预压验收标准中的实际应用  

Practical application of vane strength in determining acceptance standard of vacuum preloading

作　　者：孙锐 单晓辉 SUN Rui;SHAN Xiao-hui(First Survey and Design Institute of Chemical Industry Co.,Ltd.,Cangzhou 061001,Hebei,China)

机构地区：[1]化学工业第一勘察设计院有限公司,河北沧州061001

出　　处：《地基处理》2023年第3期248-254,共7页Journal of Ground Improvement

摘　　要：针对当前真空预压施工质量验收中出现强度低、难以验收的问题,本文讨论了在设计阶段如何合理确定验收标准,尽量避免此类问题发生。提出了应用实测十字板测试数据,确定处理后地基土强度验收标准的必要性。提出了用十字板随深度回归值线估算初始值,迭代运算淤泥土内摩擦角,进而推算预压后地基强度的方法。对于现行标准基于有效固结应力法,计算的土体固结产生的强度增量大于实测结果,实际工作中应该如何应用的情况,建议依据处理前十字板随深度回归值线直接预估处理后增长的强度,作为处理后最低要求的观点,方便行业内实际操作。对真空预压设计单位给出了相应建议,不能只要求固结度、地基土承载力特征值等主要参数,还应规定对应深度的十字板应达到的抗剪强度及最低值,以指导施工,方便参建单位多方验收。Aiming at the problems of low strength and difficulty acceptance in the current period of vacuum preloading construction quality acceptance,this work discusses how to reasonably determine the acceptance standards in the design stage to avoid such problems as much as possible.The necessity of applying the test data of the vane plate to determine the acceptance standard of the strength of the treated foundation soil is developed.A method of estimating the initial value with the regression value line of the vane plate along with the depth is proposed,then iteratively calculating the internal friction angle of the silt soil,and finally estimating the method of the foundation strength after preloading.The strength increment of soil consolidation calculated based on the effective consolidation stress method in the current standard is greater than the measured results.Therefore,this paper proposes to directly predict the growth intensity after treatment according to the regression value line of vane plate before treatment with depth,as the minimum requirement after treatment.Some suggestions are proposed for the vacuum prepressing design company:not only the characteristic parameters of consolidation and foundation soil bearing capacity;also the shear strength and the lowest value that the vane plate at the corresponding depth should be specified to guide the construction and facilitate the acceptance of the participating companies.

关 键 词：真空预压 十字板强度 回归直线 迭代法 内摩擦角 验收标准 

分 类 号：TU47[建筑科学—结构工程]