Analysis of Geological Characteristics of Tunnel Engineering in Tuoluo Rotational Tectonic Belt
Research purposes:A railway tunnel in the southwest passes through the Tuoluo rotational tectonic belt.In order to identify the geological conditions of the railway tunnel engineering in its pillar and rotation layer,this paper explores its basic characteristics,genetic mechanism,and stress characteristics through comprehensive exploration methods such as field geological investigation,drilling,geophysical exploration,and indoor testing.Based on this,three areas are divided and combined with the actual situation of tunnel construction to verify and analyze the geological characteristics of the tunnel engineering within the rotational tectonic belt.Research conclusions:(1)The Tuoluo rotational tectonic belt is a clockwise knob converging towards the southwest direction,mainly composed of a circular pillar and two cyclic layers.(2)According to the theory of"infinite plate concentrated force couple",it is speculated that the influence range of the spiral stress field in the rotational tectonic belt is about 65.3 km.(3)The rotational tectonic belt is developed in the red soft rock layer,and the integrity of the pillar rock mass is slightly better.The overall physical and mechanical properties are better than those of the spiral layer,but there is no obvious distribution difference in the rock structure type.(4)The construction of spiral layer tunnels is more prone to encountering engineering geological problems such as water inrush,large deformation of soft rock,high ground temperature,radioactivity,and goaf.(5)The development of adverse geological conditions on the surface is mainly controlled by rotary structure circular faults and spreading faults.(6)The research results can provide reference for geological route selection and tunnel engineering survey and design of railways and highways crossing areas with similar geological structure.
NETL
NSTL
万方数据
