下穿高速公路箱涵方案比选与顶推施工设计

Scheme Comparison of Under Passing Highway and Design of Jacking Method

结合下穿襄荆高速公路的箱涵工程特点,先从施工风险、工期、造价以及对周围环境影响等角度对比分析箱涵顶推、浅埋暗挖及明挖3种施工方案,突显箱涵顶推法在实际工程应用中的优势;再进行施工过程中顶推力大小设计,并验算后部土体的稳定性;最后利用有限元软件开展顶推过程中可能出现的既有道路沉降分析。研究结果表明,顶推工法方案设计合理可行,能保证施工安全和既有道路的稳定性。

According to the characteristics of box culvert engineering of Xiang-Jing Expressway,three construction schemes of box culvert jacking,shallow buried underground excavation and open excavation are compared and analyzed from the aspects of construction risk,construction period,cost and impact on the surrounding environment,highlighting the advantages of box culvert jacking method in practical engineering application.Then based on the friction resistance of the surrounding soil in the jacking process,the design of the jacking force in the construction process was carried out,and the stability of the soil at the back was checked.Finally,the possible settlement of existing road in jacking process is analyzed by using finite element software.The results show that the design of jacking method is reasonable and can ensure the safety of construction and the stability of existing roads.