Abstract: Based on long-term mine pressure monitoring, mechanical properties test results, mineral composition analysis and broken zone detection results of surrounding rock in Zhaozhuang mine, the deformation and failure characteristics of surrounding rock were analyzed, and the instability mechanisms were also revealed. The dynamic superposition coupling support technology composed of reserving deformation, bolt-net-anchor-spout coupling support and bolt-grouting support was proposed for the extremely fractured and soft roadway. The effects of dynamic superposition coupling support technology were verified by similar model test and engineering practice. The study shows that the deformation of the surrounding rock can be effectively controlled by means of releasing deformation energy and high stress in surrounding rock through reserving deformation, high prestressed cables in the roof, high prestressed bolts and low prestressed cables in the sides to achieve the goal of pressure relief and roof control, the combination of low pressure filling and high pressure permeation grouting to form the positive and effective bolt-grouting support and multilayer composite beams structure, and bolt-grouting support to control floor heave.

Key words: fractured surrounding rock, soft rock roadway, deformation instability, coupling support, control technology