针对综放工作面末采阶段支架回撤过程中容易出现压架的问题,建立了顶板断裂来压力学模型,并根据顶板断裂前后的平衡方程推导出顶板在不同断裂形式下支护体、煤体内应力增量平均值的统一表达式.以神东矿区多通道快速回撤技术模式为研究对象,根据顶板断裂面与主回撤通道的位置关系分两种情况进行了力学分析,结果表明:工作面回撤停采的合理位置应能够使主回撤通道处于顶板断裂面以外;回撤期间利用停采让压原理调节周期来压步距,采取在主撤巷道内加强支护、控制贯通前后工作面高差等措施,能有效保证综放工作面末采阶段的安全高效回撤.%Aiming at the problem of support crushing in the process of support withdrawing at the terminal mining stage of the fully mechanized top-coal caving face, a mechanical model of roof rupture weighting was established, and the unified expression for the stress increment average values in the support body and coal mass in different roof rupture forms was derived according to the equilibrium equations before and after the roof rupture. Taking the multichannel rapid support withdrawing mode used in Shengdong Coal Mining Area as the research object and based on the position relation between the roof rupture surface and the main withdrawing channel, the mechanical analysis in two cases was conducted. The results showed that the reasonable position for support withdrawing and mining termination should enable the main withdrawing channel to be located beyond the roof rupture surface; and during the support withdrawing, the adjustment of the periodical weighting step distance with the mining termination yielding principle, the strengthening of support in the main withdrawing roadway and the control of the height difference of the working face before and after cutting through can effectively ensure the safe withdrawing of face support at the terminal mining stage of the fully mechanized caving face.
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