Research on the Deformation Mechanism and Control Technology of the Floor in Deep Soft Rock Roadway

Due to the influence of high crustal stress, weak surrounding rock, and other factors, deep soft rock roadways are often in complex stress states. This study takes the III4104 roadway as the research object to reveal the deformation mechanisms of deep soft rock roadways, aiming to effectively address the support challenges faced by such roadways. Firstly, a field survey summarized the failure characteristics of deep soft rock roadway and analyzed the causes of failure. Secondly, a mechanical model of floor heave was established, and the maximum depth of floor damage was calculated. Subsequently, based on the UDEC Trigon method, a discrete element numerical model that meets engineering scale was constructed, and a correction method for model parameters was proposed. Through simulation research, the deformation characteristics of surrounding rock, displacement vector distribution, crack distribution, and plastic zone extent were explored. Finally, a combined control technology of “roof corner anchor cable + rib anchor cable + concrete inverted arch + floor anchor cable” was proposed, along with specific parameters, and successfully applied in the III4104 roadway. The application results showed that, after 50 days of monitoring, the surrounding rock deformation stabilized, with the overall deformation rate controlled within 5%, indicating good control performance. The research results provide technical assistance for the stable control of surrounding rock deformation in deep soft rock roadways.