Grouting In The Dark Hole Of Collapsible Loess Roadbed Processing

Nowadays, the progress of expressway is very quick, but there still are some problems .How to survey and treat tunnels in roadbase is one important task. Collapse area tunnels in roadbase treated by the grouting is one task of China Transplation Darpartment science item "Survey the Tunnel in Collapse Area". The paper mainly studied using the grouting treat tunnels in roadbase in collapse area.Firstly, the spread law of tunnels is conclused and analised: tunnels often occurs in gully of loess ridge or where face gully and the connection of embankment and cutting. Collapse,sink and open up are the harm that often done by tunnels. The breadth treated is the spot among 30~50m above the embankment and cutting ,and 10~20mlow.Secondly, the theory is permate and extrude, and the globe spread theory, pill spread theory are analysised. The theory of the grouting belongs to filling, in order to reduce cement and money coal power is used. Additive is used to change the intensity, condensation and circulation to accelerate the construction.The machinery is introduced in the paper. The radius of the grouting is l~1.5m, and the pressure is 0.1~0.2Mpa.Finally, proved by two engineerings ,the grouting has a good effect , and is economic.