Settelment Monitoring And Rule Research Of Rock Tunnel Roof Rock Massin The Shallow Tunnel Excavation

This article rely on the monitoring measurement of Alatan tunnel project, research the program design, data processing, as well as in practical engineering applications of vertical displacement measurement of the shallow tunnel section roof surrounding rock by real-time and full-time displacement changes, and made the following main results:1. To establish a set of practical and effective displacement measurement technical methods of tunnel roof rock mass, solved the lag and incomplete of measurement information effectively, so that rock mass information be a complete reflection in the first time.2.The paper discusses the generation mechanism of shallow tunnel roof rock mass displacement, proposes the displacement generation of highway tunnel surrounding rock have not only relevant with geological factors, but also with the design parameters and construction methods and other factors of tunnel, and find that tunnel construction footage is the the main factor.3.The paper also has studied the deformation features of tunnel roof rock mass in the stability situation: the largest deformation point in the vicinity of vault and it is the center point of expansion. The trend of expanding of both sides is greater than the surface. Due to the continuity of strata, deformation features is similar with tunnel vertical or horizontal; but because of the discreteness of rock material, the vertical settlement from tunnel roof to ground surface after excavation is large when close to tunnel roof and small when far from tunnel roof.4.The first time in summing up the complete deformation rule of tunnel roof surrounding rock by the promoting of working face (tunnel face) , and summed up the vertical displacement of tunnel roof surrounding rock showed settlement trough form by the tunnel horizontal, and closing to the formula peck.Engineering practice has proved that the application of this article researchs results for Alatan tunnel construction and has provided that the basis for follow-up at the same time a similar project design and construction experiences.So results of this article have the great value to promotion.