基于数值模拟的开槽法测量混凝土工作应力研究  

Study on in-situ stress of concrete measured by slotting method based on numerical simulation

作　　者：张一[1] 徐赵东[1] 李今保[2] 郭迎庆 ZHANG Yi;XU Zhaodong;LI Jinbao;GUO Yingqing(China−Pakistan Belt and Road Joint Laboratory on Smart Disaster Prevention of Major Infrastructures,Southeast University,Nanjing 210096,China;Southeast Special Engineering Co.Ltd.,Nanjing 210008,China;Nanjing Dongrui Damping Control Technology Co.Ltd.,Nanjing 210033,China)

机构地区：[1]东南大学中国−巴基斯坦重大基础设施智慧防灾一带一路联合实验室,江苏南京210096 [2]江苏东南特种技术工程有限公司,江苏南京210008 [3]南京东瑞减震控制工程有限公司,江苏南京210033

出　　处：《中南大学学报（自然科学版）》2023年第5期1885-1893,共9页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金重点资助项目(52130807);江苏省前沿引领技术基础研究重大项目(BK20222006)。

摘　　要：提出一种基于应力释放原理测量混凝土工作应力的分步开槽检测方法,针对单向应力状态下的混凝土受压构件,采用数值模拟的方法分析开槽形状、开槽间距、开槽长度以及开槽深度等因素对应力释放程度的影响。研究结果表明:开槽形状为横槽时,开槽间距越小,开槽长度越长,应力释放越快;开槽形状为方槽时,开槽间距越小,应力释放越快,而开槽长度对方槽的应力释放影响较小;当开槽深度为0~40 mm时,方槽与相同开槽间距、长宽比λ>1的横槽可以相互替换,两种情况中心测点处的应力差值较小。当应力释放时,槽内区域比槽外区域的应力变化更敏感和准确,开槽法解决了圆孔法孔内应变信息无法连续输出的问题。通过测量每步开槽深度下的应力释放值,与数值模拟的结果相结合,利用多步优化结果反推测点处工作应力,减小测量误差。A step-by-step slotting measurement method based on the stress-release method was proposed to measure in-situ stress of concrete.For concrete compressed members under unidirectional stress,numerical simulation was used to analyze the effects of slotting shape,slotting spacing,slotting length and slotting depth on stress-release degree.The results show that the stress is released faster with the smaller slotting spacing and the longer slotting length when the slotting shape is horizontal.The stress is released faster with the smaller slotting spacing when the slotting shape is square and the slotting length has less influence on the stress release of the square slot.When the slotting depth is 0-40 mm,the square slot can be replaced with the horizontal slot of the same slotting spacing and aspect ratio λ1,and the stress difference at the center measurement point of two cases is small.When the stress is released,the stress change in the area inside the slot is more sensitive and accurate than that in the area outside the slot.The slotting method solves the problem that the strain information inside the hole of the circular hole method cannot be continuously output.By measuring the stress release value at each slotting depth step and combining it with the results of numerical simulation,the multi-step optimization results can be used to infer the working stress at the measurement point and reduce the measurement error.

关 键 词：建筑结构 应力释放法 数值模拟 工作应力 开槽法 

分 类 号：TU375[建筑科学—结构工程]