摘要
地铁基坑一般都采用地下连续墙+横向支撑+立柱桩支护形式,立柱桩上部为格构柱,下部为钻孔灌注桩。为施工方便,部分格构柱和钢筋笼焊接一起下放,但在浇筑混凝土时易出现堵塞、返浆、卡管及错位等问题,当导管发生卡管时无法继续浇筑混凝土,处理不当会出现混凝土初凝导致断桩。目前工程界对卡管事故的处理方法研究甚少,为解决可能发生卡管的事故,针对导管接头法兰与格构柱发生卡结、导管错位并破坏钢筋笼等问题进行分析,并提出有效对策:首先在导管接头法兰处安装锥形套,使法兰凸出截面由小截面逐渐过渡至法兰盘大截面,避免法兰破坏钢筋笼箍筋并使其顺利下放;其次用12根Φ10mm光滑圆筋连接格构柱底端与其下第一道箍筋形成一个滑坡面,保证了导管在格构柱底端不会发生卡结。有效地解决了工程常见的卡管及错位问题,为提高工程质量及施工速度提出了新的解决思路和参考。
The underground pit is generally supported by a diaphragm wall+lateral support+column piles,with the upper part of the column piles being lattice columns and the lower part being bored piles.For construction convenience,some of the lattice columns and reinforcement cages are welded together and lowered,but when pouring concrete,problems such as blockage,back slurry,pipe jamming and misalignment are likely to occur,and when the conduit is stuck,concrete cannot be poured,and improper handling will lead to concrete initial setting and pile breakage.At present,there is little research in the engineering field on the handling method of the stuck pipe accident.To solve the accident that may occur,we analyze the problems of stuck joints between the flange of the conduit joint and the lattice column,misalignment of the conduit and destruction of the reinforcement cage,and put forward effective countermeasures:firstly,we install a conical sleeve at the flange of the conduit joint,so that the flange protrudes from the small section to the large section of the flange gradually,avoiding the flange from destroying the reinforcement cage hoop and making Secondly,12 Φ 10mm smooth round bars were used to connect the bottom end of the lattice column with the first hoop under it to form a slippery surface,which ensured that the conduit would not get stuck at the bottom end of the lattice column.It effectively solves the common problems of stuck and misplaced conduits,and presents a new solution and reference for improving the quality and speed of construction.
作者
阮永芬
梁龙元
乔文件
胡经魁
蔡龙
RUAN Yong-fen;LIANG Long-yuan;QIAO Wen-jian;HU Jing-kui;CAI Long(School of civil Engineering and Mechanics Kunming University of Science and Technology,650500,Kunming,China;Engineering Corporation Limited of CR20G,650000,Kunming,China;Kunming Prospecting Design Institute Of China Nonferrous Metals Industry Co.,Ltd.,650051,Kunming,China)
出处
《建筑技术》
2023年第4期455-459,共5页
Architecture Technology
基金
云南省重点研发计划项目(2018BC008)
中铁二十局集团第五工程有限公司科研计划项目(CR2005–5–JS–2021–009)。
关键词
地铁深基坑支护
格构柱桩
卡管
错位
subway deep foundation support
lattice column pile
jamming tube
misalignment
