为研究长边煤柱(采空)条件下基本顶板结构的破断规律及工程价值.构建考虑长边煤柱宽度及承载能力与实体煤弹塑性软化特性的基本顶板结构力学模型.全面计算探究该条件下基本顶板在长边煤柱区及实体煤区的断裂位置.顺序及形态.并从6个层面.3个区域与传统模型对比.阐述模型所得新结论及意义.结论如下:① 长边煤柱宽度与承载能力可显著影响实体煤区基本顶主弯矩大小及初次破断顺序.但是对实体煤区基本顶破断线所处区位(弹性区.塑性区.弹塑性分界区)影响小.长边煤柱也可显著改变基本顶在煤柱区的破断位态(3类).且随基本顶的弹性模量E及基本顶厚度h增大.长边煤柱的支撑系数kcm.宽度Lcm.实体煤的塑化范围Lt-s.塑化程度ks-0.弹性煤体基础系数ktt及工作面跨度Ld减小.其演变模式为:1条连续[长直线+两端短弧线"型(CM-N式)→2条临接对称[直线+短弧线"型(CM-L式)→2条大间距对称[短弧线"型(CM-D式),② 实体煤的长边与短边区基本顶破断线的区位特征有5类.且随着E及h增大.Lt-s.ks-0.ktt及Ld减小时的演变规律为:长.短边破断线均处于塑化煤体区→长边破断线在煤体弹塑性分界区.短边破断线在塑化煤体区→长边破断线在弹性煤体区.短边破断线在塑化煤体区→长边破断线在弹性煤体区.短边破断线在弹塑性分界区→长边与短边破断线均在煤体弹性区,③ 基本顶的整体破断模式有3类.且随E及h增大.kcm.Lcm.Lt-s.ks-0.Ld及ktt减小时的演变模式为:闭合断裂圈非对称[-X"型→临接闭合断裂圈非对称[-X"型→开口局部断裂圈非对称[-X"型.针对研究长边煤柱(采空)基本顶板结构破断的3类力学模型.从6个层面对比了模型的重要区别.从3个区域(长边煤柱区.短边区.长边区)阐明了其工程价值.

In order to study the fracture law and engineering value of the main roof plate structure under the condition of long side coal pillar (goaf).the main roof plate structure mechanical model considering the width and bearing capacity of long side coal pillar and the elastic-plastic softening characteristics of solid coal is constructed. The fracture position.sequence and shape of the main roof above the long side coal pillar area and solid coal area are comprehensively calculated and investigated. Compared with the traditional model from six levels and three regions.this paper expounds the new conclusions and significance of this model. The conclusions are as follows. ① The width and bearing capacity of the long side coal pillar can significantly affect the principal bending moment and the fist fracture sequence of the main roof above the solid coal area.but have little impact on the location of the main roof fracture line above the solid coal area (elastic zone.plastic zone and elastic-plastic boundary zone). The long side coal pillar can also significantly change the fracture position state of the main roof above the coal pillar area (three types).and with the increase of E and h of the main roof.the support coefficient kcm and width Lcm of the long side coal pillar.the plasticization range Lt-s.plasticization degree ks-0.solid coal foundation coefficient ktt of solid coal and working face width Ld decrease. Its evolution mode is that one continuous [long straight line+short arc at both ends" type(CM-N)→ two adjacent symmetrical [straight line + short arc" type(CM-L)→two large spacing symmetrical [short arc" type (CM-D). ② There are five types of location characteristics of the main roof fracture line above the long side and short side areas of solid coal. With the increase of E and h.when Lt-s,ks-0,ktt and Ld decrease.the evolution law is as follows:the long side and short side fracture lines are above the plasticized coal body area→the long side fracture line is above the elastic-plastic boundary area of coal body.and the short side fracture line is above the plasticized coal body area →the long side fracture line is above the elastic coal body area.the short side fracture line is above the plasticized coal body area→the long side fracture line is above the elastic coal body area.and the short side fracture line is above the elastic-plastic boundary area→both the long side and the short side fracture lines are above the elastic coal body area. ③ There are three types of overall fracture modes of main roof.and with the increase of E and h.and with the decrease of kcm.Lcm.Lt-s.ks-0.Ld and ktt.the evolution mode is as follows:Asymmetric [width=37,height=22,dpi=110-X" type of→asymmetric [width=36,height=18,dpi=110-X"→asymmetric [width=38,height=21,dpi=110-X" type. Aiming at the three kinds of mechanical models for studying the fracture of the main roof plate structure with long side coal pillar (goaf).the key differences of the models are compared from six levels.and its engineering value is expounded from three areas ( long coal pillar area.short side area and long side area).

1 长边煤柱(采空)边界条件对比

2 长边煤柱(采空)基本顶板结构模型

   2.1 力学模型

   2.2 边界条件

3 模型解算及破断准则

   3.1 解算方法

   3.2 破断分析方法

4 长边煤柱+弹塑性基础边界条件下的基本顶板内力特征及破断模式分析

   4.1 非煤柱区基本顶主弯矩特征及破断模式

   4.2 煤柱区基本顶主弯矩特征及破断模式

   4.3 长边煤柱+弹塑性基础边界基本顶板结构破断模式

   4.4 破断模式的研究因素分类

5 破断模式的基本顶因素效应(间接)

   5.1 破断顺序方面

   5.2 实体煤区断裂形态及区位特征方面

   5.3 煤柱区断裂形态及区位特征方面

   5.4 基本顶断裂区位特征及整体形态方面

6 破断模式的长边煤柱效应(直接)

7 破断模式的实体煤效应(直接)

8 破断模式的跨度效应(间接)

9 与传统模型结论及指导意义对比

   9.1 基本结论方面

   9.2 工程指导意义分类

10 结论