Aimed at the characteristics of low-burying medium-hard and extremely thick coal seam,different mining face length and mining height,varying rules of advanced abutment pressure and damage height of overburden strata are researched with numerical simulation,thereby the mining face length and mining height are optimized,reasonable mining face parameters are acquired.
针对浅埋深中硬特厚煤层特点,通过数值模拟,研究不同工作面长度和采高,前方支承压力变化规律以及上覆岩层破坏高度,从而对工作面长度和采高进行优化,得出中硬特厚条件下合理工作面参数。
The analysis and experiments suggest that the revised design of the medium_and_concave hobbing cutter effectively controls the digital ratio and the direction of the medium_and_hard gear errors, guarantees the position and width of the auxiliary contact zone of gears and meets the requirement of design and utilizati.
分析和试验表明 ,滚刀中凹修形可有效地控制中硬齿轮齿形误差的数值和方向 ,能保证齿轮副接触带的位置和宽度 ,符合设计与使用要
For the research on characters of cemented soil of SMW(soil mixing wall) technology in medium-hard strata is shortage,so the application in medium-hard soil is restrained.
针对SMW工法缺乏对中硬地层的水泥土性能研究,利用首例北京地区在中硬地层中地铁基坑工程采用SMW工法搅拌后的水泥土,进行了三轴压缩试验。
Through the crack test of big medium hard coal samples from Wangzhang Mine on real triaxial test machine , the fundamental properties of strength and deformation are obtained and the crack evolutionary way is discussed .
在真三轴压力机上通过对王庄矿中硬煤大煤样的压裂实验 ,得出了中硬煤在强度、变形方面的基本力学特性 ,探讨了中硬煤的裂隙演化过程 ,即裂隙演化经历扩展、加密、再扩展和再加密等过
It is studied that alkaline cooling water treatment program based on improved drug TS-219 and pH control is used to treat make up water of high alkalinity normal hardness under the condition of high cycle of concentration.
介绍了大庆炼化公司循环冷却水系统采用改进配方TS - 2 19及对pH值进行控制的碱性运行方案 ,对高碱中硬型补充水在高浓缩倍数下运行进行了试验研究。