公路工程

大角山隧道是广州市南沙区第一条城区山岭隧道，是打通大角山屏障，连接港前大道与环市大道的重要骨架通道之一。项目周边环境复杂，线位穿越地铁15号线、国家级文物大角山炮台等多处敏感环境控制点，设计和施工难度极大。为解决周边敏感环境与项目的相互制约，采用资料收集、文献调研、现场勘察、理论分析和经验总结等手段，对大角山隧道工程总体设计和控制关键节点进行分析研究，结果表明：(1)工程总体方案和施工工法经济最优、工期合理，方案可行；(2)综合考虑周边管线、相交道路、沿线树木和地铁15号线等因素，合理选择最优路线，最大程度上节约了资源、减小了对景观的破坏；(3)通过比选市政电力管线过隧道方案，选取最优的排管方案，为类似电力管线过隧道工程提供一定的借鉴参考；(4)结合爆破方案设计，通过数值模拟、理论分析爆破允许安全距离和单次最大装药量等因素，采用合适的爆破方法和施工方案，确保文物的安全；(5)洞口超小净距段采用地面注浆、对拉锚杆和小导管注浆的工法，保证隧道施工的安全性。

The first urban mountain tunnel in the Nansha District is dajiaoshan tunnel. It is one of the important skeleton channels to open up the dajiaoshan barrier and connect Gangqian Avenue and Huanshi Avenue. Due to the design line passes through many sensitive environmental control points such as the national cultural relic dajiaoshan fort, so the design and construction are very difficult under the surrounding environment. In order to solve the mutual restriction between the surrounding sensitive environment and the project, the overall design and the key techniques of dajiaoshan tunnel project are analyzed and studied by means of data collection, literature research, field investigation, theoretical analysis and experience summary. The results show that:(1)the overall scheme and construction method of the project are economical, and the construction period is reasonable and the scheme is feasible;(2)the optimal route shall be reasonably selected by comprehensively considering the surrounding pipelines, intersecting roads, trees along the line and Metro Line 15 are saves resources and reduces the damage to the landscape to the greatest extent;(3)the optimal pipe scheme is selected according to comparing and selecting the schemes of municipal power pipeline passing through the tunnel, which provides a certain reference for similar project in the future;(4)according to the blasting scheme design, and by analyzing the factors such as the allowable safe distance of blasting and the maximum charge per time, appropriate blasting methods and construction schemes are adopted to ensure the safety of cultural relics;(5)the construction methods of ground grouting, split anchor bolt and small duct grouting are adopted for the ultra small clear distance section at the portal to ensure the safety of tunnel construction.