immediate roof

stability monitoring of immediate roof in fully-mechanized top-coal caving face with high output and high efficiency

高产高效综放工作面直接顶稳定性监测

immediate roof type ii is not suitable for large mining-height technique.

II型直接顶暂不宜采用大采高开采技术；

according to stratum quality index, this paper established classification norms of immediate roof and main roof.

本文依据岩层质量指数，建立了直接顶和老顶的分类准则；

since lump size of upper-immediate roof is large, a semi-arch equilibrium structure of the stratum-rock sometimes can be formed.

上位直接顶岩块强度较高、块度较大，容易形成“岩-矸”半拱式平衡结构。

Simulation testing and theoretical analysis were made to study generating mechanics and moving evolutionary process of "granular arch" structure of upper immediate roof in top coal caving.

通过相似模拟实验和理论分析，研究了综放条件下上位直接顶“散体拱”结构的形成机理和移动演化过程。

influence of cycle caved height of immediate roof on stability of its first layer

直接顶循环垮落高度对其第一分层稳定性的影响

although the immediate roof of baidong colliery is relatively soft, its basic roof is glutenite and difficult to control.

白洞煤矿采场顶板中虽然直接顶较松软，但基本顶岩层为砂砾岩，属于难控顶板。

first of all, based on the field analysis of very soft coal fully mechanized face immediate roof and the movement of top coal.

首先，根据现场实际分析极松软煤层综放工作面直接顶和顶煤的运动形式；

critical height of immediate roof and working resistance of support

直接顶的临界高度与支架工作阻力分析

The outport bears the load of top-coal and breaks immediate roof.

支架承受的是上方煤体和折断部分直接顶的载荷.

modelling experiment for immediate roof with many cracks caving in longwall face

采场多裂隙直接顶破坏的模拟研究

the balance structure of main roof and its action to immediate roof in large cutting height workface

大采高开采上位岩层平衡结构及其对采场矿压显现的影响