Abstract: With coal mining extending to deeper underground strata, soft rock roadways are subjected to harsh operating environments characterized by severe erosion, high ground temperature, high seepage pressure, high in-situ stress and strong dynamic disturbance. These adverse conditions induce intense surrounding rock deformation, severe floor heave as well as large-scale sidewall deformation and rock burst. Traditional support schemes fail to adapt to such complex conditions due to concrete deterioration and insufficient floor bearing capacity. To address the above key problems, a composite support system consisting of high-strength steel mesh shell, shotcrete and rock bolts is proposed. Its bearing performance and engineering applicability are systematically investigated via numerical simulation, similar model tests and field industrial tests.Taking the roadways of Dingji Coal Mine as the engineering background, a three-dimensional numerical model is established using SIMULIA-Abaqus（ABAQUS）. Three key parameters, namely the embedded depth of high-strength mesh shell in the floor, longitudinal bar diameter and concrete strength grade, are selected, and a total of 16 working conditions are designed based on the orthogonal test method. The results reveal that the influencing degree of each parameter on support performance follows the order: embedded depth > concrete strength > longitudinal bar diameter. The optimal parameter combination is determined as an embedded depth of 1.0 m, longitudinal bar diameter of 12 mm and C20 concrete, under which the floor heave reaches the minimum value of 14.32 mm. The proposed composite support optimizes the stress transfer path through a compression-dominated and tension-compression coordinated mechanical mechanism.In accordance with similarity theory, a physical model is constructed, and non-uniform stress field model tests are conducted on a large-scale multi-directional independent loading test system for surrounding rock-support coupling. The whole process of deformation and failure of roadway surrounding rock and support structures is reproduced. The test results demonstrate that the high-strength mesh shell composite support possesses much better resistance to non-uniform stress and crack propagation inhibition capacity than conventional supports, which also verifies the reliability of displacement and stress evolution laws obtained from ABAQUS numerical simulation.Field industrial tests are carried out in the main track roadway at Level 910 of Dingji Coal Mine. Combined with ceramsite and rice husk ash fiber reinforced concrete (Ceramsite-Rice-Husk-Ash Fiber Concrete, CRHAFC), the proposed composite support reduces the roof-to-floor convergence by 38% and sidewall convergence by 45% compared with conventional supports. After 60 days of operation, the sulfate erosion depth decreases from 12.0 to 4.6 mm, and the carbonation depth drops from 8.0 to 5.0 mm. In addition, rice husk ash realizes the resource utilization of agricultural solid waste, and the internal curing effect of ceramsite cuts down the maintenance cost, which complies with the construction requirements of green mines.The research outcomes effectively improve the stability of deep soft rock roadways, and provide theoretical basis and technical support for support engineering under complex geological conditions.