摘要
近年来盘扣式钢管支架在隧道顶板施工中的应用越来越普遍,常规方式采用后装法监测立杆轴力,安装传感器时调节立杆顶托导致轴力重新分布,监测轴力精度不足。本文提出先装法进行监测,通过实际监测案例,分别采用先装法和常规后装法进行监测对照试验,对比规范理论计算轴力值,对监测结果进行对比分析,探究盘扣式钢管立杆轴力监测方法。研究结果表明:(1)与常规后装法比较,本文提出先装法更接近高支模立杆轴力实际受力情况(2)JGJ231-2021规范对高支模轴力的理论计算值大于本次试验实际监测轴力值,验证了规范计算轴力值偏安全(3)采用后装法和先装法得到立杆轴力值,存在较大差异,后装法得到的轴力值结果偏小,相比对照组偏小15.64%和相比参考点偏小37.8%(4)采用先装法对比后装法轴力值更接近理论轴力值。先装法的轴力值和理论值的比率MA/N为0.49,常规后装法的轴力值和理论值的比率MB/N和Mc/N分别为0.419和0.309。本文提出先装法更接近于实际受力情况,研究结果可对常规高支模监测和施工进行校正和补充。
In recent years,the application of disc buckle steel pipe support in tunnel roof construction is becoming common.The conventional way is to use the rear loading method to monitor the vertical rod axial force,and adjusting the vertical rod top support when installing the sensor leads to the redistribution of axial force and the lack of monitoring axial force accuracy.In this paper,the preloading method is proposed for monitoring.Through the actual monitoring cases,the monitoring control tests are carried out by using the preloading method and the conventional afterloading method,and the axial force values are calculated by comparing the standard theory,the monitoring results are compared and analyzed,and the axial force monitoring method of disc buckle steel pipe vertical rod is explored.The results show that:(1)compared with the conventional postloading method,this paper proposes that the preloading method is closer to the actual axial force of the high-support die vertical rod.(2)the theoretical calculation value of the axial force of the high support die in the JGJ231-2021 code is larger than that of the actual monitoring axial force in this test,which verifies that the axial force calculated by the code is safe.(3)there is a big difference between the axial force value of the vertical rod obtained by the afterloading method and the preloading method,and the axial force value obtained by the postloading method is 15.64%smaller than that of the control group and 37.8%smaller than the reference point.(4)the axial force value of the preloading method is closer to the theoretical axial force value than that of the rear loading method.The ratio of axial force value of preloading method to theoretical value MA/N is 0.49,and the ratio of axial force value of conventional afterloading method to theoretical value is 0.419 and 0.309 respectively.It is proposed that the preloading method is closer to the actual stress situation,and the research results can correct and supplementthe conventional high-supported formwork mon
作者
倪毅
邵泉
张厚美
黄桂明
蒋永新
NI Yi;SHAO Quan;ZHANG Hou-mei;HUANG Gui-ming;JIANG Yong-xin(Guangzhou Construction Co.,Ltd,,Guangzhou 510030;Guangzhou Municipal Construction Croup Co.,Ltd.,Guangzhou 510030;Guangzhou Hengsheng Construction Group Co.,Ltd.,Guangzhou 510030)
出处
《广州建筑》
2024年第5期53-57,共5页
GUANGZHOU ARCHITECTURE
基金
广州市建筑集团有限公司科技计划项目(2023-KJ026)。
关键词
承插型盘扣式钢管
高大模板支撑体系
立杆稳定性验算
立杆轴力监测
disk lock steel tubular
tall formwork support check the stability of vertical rod
vertical rod axial force monitoring
