摘要
结合武汉市重点工程东湖通道团山隧道项目小净距隧道的工程实际,进行施工工序的优化,改交叉中隔壁法(传统CRD法)为优化后的交叉中隔壁法,提出拆除临时抑拱和中隔壁以利于大型挖机掘进的施工;将摩尔-库仑等面积圆屈服准则代替传统摩尔-库仑准则,建立小净距隧道施工工序优化的有限元分析模型,对不同施工工艺情况下,隧道开挖过程中岩土体受力情况进行了数值模拟分析。结果表明:优化施工工序满足应力应变要求。研究小净距隧道施工优化方案爆破开挖安全性,进行爆破动力响应的二维弹塑性时程分析;研究分析爆破震动作用下初衬动力反应,通过现场实测波形结果,评价按施工下部导洞前拆除临时仰拱的CRD法条件下围岩抗震动的安全性。从而顺利完成了施工,既降低了施工成本、又缩短了施工工期。该研究结果对今后类似小净距隧道的施工具有重要的指导意义。
Combined with the engineering practice of small-distance tunnel in Donghu Channel Tuanshan Tunnel Project of the major projects in Wuhan, the construction procedure is optimized, the cross diaphragm method(traditional CRD method) is changed into the optimized CRD method, and the temporary inverted archand center diaphragm are dismantled to facilitate the tunneling construction by the large excavator.Mohr-Coulomb equivalent area circle yield criterion replaces the traditional Mohr-Coulomb criterion. The finite element analysis model is established to optimize the construction procedure of small-distance tunnel.The stress state of rock-soil body in the excavation of tunnel is numerically simulated and analyzed under the different construction technologies. The result shows that the optimized construction procedure meets the requirements of stress and strain. This paper studies the blasting excavation safety of small-distance tunnel construction optimization scheme. The two-dimension elastic-plastic time-history analysis of blasting dynamic response is carried out to study and analyze the primary lining dynamic response under the action of blasting vibration. The in-situ measured waveform result can evaluate the safety against vibration of surrounding rock according to the CRD method to dismantle the temporary inverted arch before the construction of lower pilot tunnel so as to smoothly complete the construction, which not only reduce the construction cost, but also shorten the construction period. This study result can provide the important guiding significance for the construction of the similar small-distance tunnels in the future.
作者
段军朝
吴贤国
李博文
王彦玉
Duan Junchao;Wu Xianguo;Li Bowen;Wang Yanyu
出处
《城市道桥与防洪》
2019年第10期135-141,M0016,M0017,共9页
Urban Roads Bridges & Flood Control
基金
国家自然科学基金项目(51378235,71571078)
国家自然科学基金项目(51308240)
国家重点研发项目(2016YFC0800208)
教育部博士后基金项目(2015M570645)
湖北省自然科学基金重点项目(zrz2014000104)
武汉市建委科技项目(201414,201619,201334)
关键词
暗挖隧道
小净距隧道
施工优化
数值仿真
爆破动力响应
excavated tunnel
small-distance tunnel
construction optimization
numerical simulation
blasting dynamic response
