施工顺序及不同管材对双层顶管隧道施工引起地表沉降的影响研究  

Influence of Construction Sequence and Different Types of Pipes on Ground Surface Settlement Caused by the Construction of Two-layer Jacking-pipes

作　　者：安关峰[1,2] 王谭 司海峰[1,2] 刘添俊 AN Guanfeng;WANG Tan;SI Haifeng;LIU Tianjun(Guangzhou Municipal Engineering Group Co.,Ltd.,Guangzhou 510060;Municipal Engineering Technology Research Institute,Guangzhou Municipal Engineering Group Co.Ltd.,Guangzhou 510060)

机构地区：[1]广州市市政集团有限公司,广州510060 [2]广州市市政集团市政工程技术研究院,广州510060

出　　处：《现代隧道技术》2019年第4期119-126,共8页Modern Tunnelling Technology

基　　金：国家科技支撑计划项目(2015BAK11B00);科技计划项目(2016-KJ002)

摘　　要：针对双层顶管施工引起地表沉降的问题及其影响因素,文章借助有限元软件建立三维模型,综合考虑机头正面推力、地层损失及注浆的共同作用,模拟计算顶管施工过程,探讨顶管施工顺序及管材对地表沉降的影响。结果表明:上下双层顶管施工引起的地层最大沉降出现在下层顶管上侧,并随着上层顶管开挖该值降低17.84%,下侧隆起值变化不大;双层顶管施工引起地表沉降的主要影响区域在顶管轴线前后及左右-3.2D1~3.2D1范围内;先行施工的下层顶管引起的地表最大沉降占总沉降的78.05%;后续上层顶管的开挖导致机头前方隆起明显,表现为总沉降减少,机头通过后地表沉降增加,最大增加21.95%,并随着顶管推进地表隆起增加及衰减的速率都有所降低;先施工上层顶管引起的地表沉降较先施工下层顶管工况增加20.5%,增幅较大;混凝土顶管施工引起的地表沉降大于钢顶管,最大增加26.13%,且地表主要受影响范围增大为-4.8D1~4.8D1。Aiming at the ground surface settlement caused by two-layer jacking-pipes construction and its influential factors, a three-dimensional model was established by finite element software to simulate and calculate pipejacking construction under considering interaction of bulkhead pressure, ground loss and grouting, to discuss the impact of construction sequence and pipe type on ground surface settlement. The results show that the maximum settlement caused by two-layer jacking-pipes construction occurs on the upper side of the lower jacking pipe and it reduces by 17.84% with the excavation of upper jacking-pipe, and the heaving at lower side barely changes;the main affected area of ground surface settlement is within the scope of-3.2 D1~3.2 D1 around the jacking-pipe axis;the maximum ground surface settlement caused by the antecedent construction of the lower jacking-pipe occupies78.05% of the total settlement;subsequent excavation of the upper jacking-pipe results in obvious heaving in front of it, the total settlement decreases and ground surface settlement increases after passing of jacking-pipe head, the maximum settlement increases by 21.95%, the increasing and attenuation rates of ground heaving both reduce with the advance of jacking-pipe;the ground surface settlement caused by the precedent construction of the upper-layer jacking-pipe increases largely by 20.5% compared with that of precedent construction of the lower-layer jackingpipe;the ground surface settlement caused by concrete jacking-pipe is larger than that of steel jacking-pipe, the maximum settlement increases by 26.13% and the affected scope increases to-4.8 D1~4.8 D1.

关 键 词：顶管施工 双层顶管 地层沉降 施工顺序 管材 数值分析 

分 类 号：U455.43[建筑科学—桥梁与隧道工程]