Research On Key Technology Of Highway Extension Project

With economic development, more and more expressways built in early time in ourcountry need to be widened and reconstructed. Because the reconstructions and Extensionsmust be based on the old expressway, there are many constraint problems need to be solvedsuch as the route fitting, the convergence of new roadbed and pavement with the old one,the detection, assessment and overlay of the old pavement, the splicing of the new and oldbridges, and the transportation organization design in the course of construction, etc. So thedifficulties of reconstructions and Extensions project are more than that of the newconstructing ones.Based on the background of HuiZhou-ShenZhen Expressway widening andreconstruction, this paper is focus on the research of the following key technologies: thedesign scheme of expressway reconstructed, widened and extended, the convergence of newroadbed and the old one and the application of Air Bubble Lightweight to solve the unevensinking on the back of bridge abutments, etc. The principles and methods of design schemeof widening, extending and reconstruction projects are proposed. Based on the analysis ofthe characteristics of the reconstructions and extensions of expressway, the key technologiesof convergence of new roadbed and the old one and the solutions to prevent the roadbedfrom longitudinal cracking are summarized. The application and key techniques of AirBubble Lightweight Concrete were discussed too.The consequent of this paper had succeeded to apply in the practical widening andreconstruction project (HuiZhou-ShenZhen Expressway). The result showed that the designscheme of this paper can efficiently solve the problems in the widening and reconstructionproject mentioned above, and the consequent provides a good reference to the similarengineering.