高速公路改扩建工程路面拼接反开挖施工技术研究

Study on Construction Technology of Pavement Splicing and Reverse Excavation for Expressway Reconstruction and Expansion Project

济青高速改扩建工程施工为边通车边施工,全程基本保四,力争不分流,特殊情况下以诱导分流为主,强制分流为辅。第一阶段施工老路正常通车运行,双向四车道通车,老路路基边坡按台阶进行开挖,路基填筑高程按照现状标高,填筑宽度按照设计标高放坡。第二阶段施工老路正常通车运行,双向四车道通车,路基段挖除左幅老路路基土路肩及路侧护栏,并在行车边缘处连续设置临时安全设施,左幅拼宽区按照现状标高铺设临时路面。第二阶段施工完成后,左幅路面处于封闭施工状态,整个路段已完成拼宽部分施工,路面拼接形式为路槽,拼接前按要求对老路硬路肩进行铣刨处理。文章结合济青高速公路改扩建工程实例,针对对新旧路基、路面拼接部位反开挖进行技术探讨,为后续改扩建工程新旧路面拼接施工积累经验。

The reconstruction and expansion project of Jiqing expressway is constructed at the same time of opening to traffic,and the four lane traffic is basically guaranteed in the whole process,striving to avoid diversion.Under special circumstances,the diversion is mainly induced,supplemented by forced diversion.Under special circumstances,the diversion is mainly induced,supplemented by forced diversion.In the first stage,the old road will be opened to traffic normally,two-way four lane road will be opened to traffic,the old road subgrade slope will be excavated by steps,the subgrade filling elevation will be based on the current elevation,and the filling width will be based on the design elevation.In the second stage,the old road will be opened to traffic normally and two-way four lane road will be opened to traffic.In the subgrade section,the subgrade soil shoulder and roadside guardrail of the left old road will be excavated,and temporary safety facilities will be set up continuously at the edge of the traffic.The temporary pavement will be laid in the left width matching area according to the current elevation.After the completion of the second stage of construction,the left pavement is in a closed construction state,and the whole road section has completed the construction of width splicing.The pavement splicing form is road trough.Before splicing,the old hard shoulder shall be milled as required.This article combines the example of the Jiqing Expressway reconstruction and expansion project,and conducts technical discussions on the reverse excavation of new and old roadbeds and pavement splicing sites,and accumulates experience for the subsequent reconstruction and expansion of new and old pavement splicing construction.