摘要
在连拱隧道中,中墙作为隧道的主要承载结构一直是设计和施工的重点。同时由于隧道地质条件和施工组织的复杂性,中墙常受到地层偏压和施工偏压两种偏压的共同作用,致使中墙内部力学状态十分复杂。施工偏压和地层偏压对中墙的影响机理互不相同,在施工过程中采取的控制措施也各不相同。利用有限元数值计算法对金鸡山双向八车道连拱隧道Ⅴ级围岩的6种施工方案进行了模拟,分析和阐述了中墙偏压产生的原因和影响因素;并结合6种施工方案的数值计算结果,对地层偏压、施工偏压对中墙影响过程进行了分析,结果表明地层偏压主要对中墙上部产生影响,而施工偏压不仅对中墙上部产生影响,而且还对中墙下部产生影响;最后,根据两种临时支护形式下中墙最终水平位移的计算结果,给出了控制中墙偏压的最佳临时支护形式。
The mid-partition of a multiple-arch tunnel is a very important part and attracts much attention in tunnel designing and constructing as it is a main support structure of the tunnel.Meanwhile,due to the complexity of geological condition and construction procedures,the mid-partition is always subjected to eccentric compression from both geological conditions and construction,which produce a very sophisticated mechanical state in mid-partition.The mechanism of influences which from these two kinds of eccentric compressions are different and their controlling measures are accordingly different in construction.Finite element analysis is adopted in analyzing 6 different construction procedures of Jinjishan multiple-arch tunnel with eight traffic lanes in class Ⅴ surrounding rock.The causation and affecting factors of eccentric compression in mid-partition is analyzed and explained.According to the 6 construction procedures,the influence from these two kinds of eccentric compression on the mid-partition is analyzed.It＇s showed that the geological eccentric compression mainly affects the upper part of the mid-partition,while the construction eccentric compression affects not only the upper part but also the lower part of the mid-partition.At the last,the optimum temporary support form to control these two kinds of eccentric compressions in mid-partition is provided by the final horizontal displacement results of two kinds of temporary supports.
出处
《地下空间与工程学报》
CSCD
北大核心
2010年第4期781-788,802,共9页
Chinese Journal of Underground Space and Engineering
基金
国家自然科学基金项目(50579088)
关键词
连拱隧道
支护结构
中墙
偏压
数值模拟
multiple-arch tunnel
supporting structure
mid-partition
eccentric compression
numerical simulation
