Key structure and bearing characteristics of 10 m super large mining height support

ZYA29000/45/100D two column shield type hydraulic support was developed for controlling the surrounding rock of a 10 m high fully mechanized mining face. Elaborated on the characteristics of rock collapse and mining pressure manifestation in the super high mining face, and summarized the support requirements for roof and coal wall protection and bearing strong dynamic loads in the 10 m super high mining face; On this basis, a 10 m super large mining height hydraulic support was developed, which is equipped with innovative structures such as double-layer telescopic beams+three-level cooperative protection, and a ø630 mm large cylinder diameter impact resistant column, and the key parameters of the structure have been provided. It has technical characteristics such as full section protection, structural impact resistance, and self stabilization of the frame; Taking structural stability as the breakthrough point, the adaptability of hydraulic supports to different working face angles and mining heights was studied, and the critical lateral tilt angle of the support is 12°, which is suitable for mining heights of 7-10 m; The force - balance area of the shield beam of the super large mining height hydraulic support is proposed. It is considered that within the normal working area of the hydraulic support, its theoretical support efficiency will not change significantly, and the load on the shield beam is the biggest difference between the super large mining height hydraulic support and the small - mining - height hydraulic support. Based on the bearing characteristics of the two column shield support, the force balance bearing area and its migration characteristics of the top beam under different support parameters were analyzed. The force balance area of the two column shield support is mainly concentrated in the column part, the change in the position of the hinge point between the upright post and the crown beam has a significant impact on the force - balance area, and the influence of changes in the balance jack parameters on the force balance area is limited; analyzed the coal wall protection performance of different types of protective structures, and clarified that the double-layer telescopic beam+three-level cooperative protective structure has obvious advantages in terms of protection strength and protection area; by analyzing the equivalent stiffness of the support in the increased resistance state, a dynamic-load mechanical analysis model of the hydraulic support was established, and the response process of the support under dynamic load in the "given deformation" working state was studied. It was found that the dynamic load borne by the top beam is mainly transmitted through the column, and the dynamic load borne by the shield beam is mainly transmitted through the four-bar linkage structure; analyzed the use of supports in the 122104 working face of Caojiatan Coal Mine, and demonstrated that ZYA29000/45/100D has good adaptability to 10 m ultra high mining face and meets the control requirements of surrounding rock for ultra high mining face.