排水板复合框架自钻胎串式锚杆支护结构的工作机制分析

发布时间：2018-03-11 17:07

  本文选题：基坑工程　切入点：排水板复合框架自钻胎串式锚杆　出处：《岩石力学与工程学报》2017年11期 　论文类型：期刊论文

【摘要】：针对软土地区的深基坑工程降水与支护问题,提出排水板复合框架自钻胎串式锚杆新型支护结构,对其结构构成和工作机制进行详细探讨。基于柱孔扩张理论,推导出自钻胎串式锚杆在孔压影响下的承载力计算公式,采用数值软件ADINA对排水板的降水效果及其对自钻胎串式锚杆抗拔承载力的影响规律进行分析,最后将承载力模拟值与理论值进行对比。结果表明:(1)排水板具有良好的降水效果,能够快速有效地消散掉含水层土体的孔隙水压力。(2)通过与无排水板的工况进行对比,得出排水板降水措施能够有效减小锚杆轴力和框架柱的水平位移。(3)排水板能够及时消散胎体膨胀引起的超孔隙水压力,随着孔压消散,土体沿锚杆轴向产生的位移和应变降低,锚杆的抗拔承载力得到提高。(4)抗拔承载力理论公式计算值与模拟值基本吻合,验证了承载力计算公式的正确性。
[Abstract]:In view of the dewatering and supporting problems of deep foundation pit engineering in soft soil area, a new type of support structure with self-drilling tire string bolt of drainage plate composite frame is put forward, and its structure and working mechanism are discussed in detail, based on the expansion theory of column hole. The formula for calculating the bearing capacity of self-drilling tire string anchor under the influence of pore pressure is derived. The effect of drainage plate and its influence on the pull-out bearing capacity of self-drilling tire string anchor are analyzed by using the numerical software ADINA. Finally, the simulation value of bearing capacity is compared with the theoretical value. The results show that the drainage board has good precipitation effect and can dissipate the pore water pressure of aquifer soil mass quickly and effectively. It is concluded that the drainage plate dewatering measures can effectively reduce the axial force of the anchor rod and the horizontal displacement of the frame column. The drainage board can dissipate the excess pore water pressure caused by the expansion of the matrix in time. With the dissipation of the pore pressure, the displacement and strain of the soil along the axial direction of the anchor rod decrease. The uplift bearing capacity of anchor rod is improved. 4) the calculated value of the theoretical formula of the uplift bearing capacity is in good agreement with the simulated value, which verifies the correctness of the formula for calculating the bearing capacity.
【作者单位】： 兰州理工大学甘肃省土木工程防灾减灾重点实验室;兰州理工大学西部土木工程防灾减灾教育部工程研究中心;中交天津港湾工程研究院有限公司;
【基金】：国家自然科学基金资助项目(51778275,51268037) 甘肃省杰出青年基金项目(145RJDA330)~~
【分类号】：TU476
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本文编号：1599097