煤岩蠕变模型与破坏特征试验研究  

Experimental study of creep model and failure characteristics of coal

作　　者：陈绍杰[1] 郭惟嘉[1] 杨永杰[1] 

机构地区：[1]山东科技大学矿山灾害预防控制省部共建教育部重点实验室,青岛266510

出　　处：《岩土力学》2009年第9期2595-2598,2622,共5页Rock and Soil Mechanics

基　　金：国家自然科学基金(50874070);教育部博士点基金(200804240004);山东省自然科学基金(Y2008F01);矿山灾害预防控制教育部重点实验室开放基金资助(MDPC0806);山东科技大学春蕾计划(2008AZZ0008)资助

摘　　要：在MTS岩石伺服试验机上对山东某矿3煤进行了短时流变试验,并对试验结果进行了分析。结果表明:该煤岩蠕变门槛系数为0.915、流变系数为0.383;煤岩流变破坏呈现空间不均匀性,整体以塑性破坏为主,但存在剪切主导破坏面;煤岩流变过程中有微破裂破坏即损伤存在,并且这种损伤在较低的应力水平就有所发生,大量微破坏的积累与贯通导致了煤岩试件破坏;煤岩蠕变过程中不仅存在损伤软化,而且存在蠕变硬化,蠕变的过程取决于这两种机制竞争的综合结果;可以用3次多项式经验蠕变模型较好地描述该煤岩的蠕变特性,西原模型可以较好地描述该煤岩的初始蠕变和等速蠕变阶段,但不能描述加速蠕变阶段。The short-time rheology tests of No.3 coal seam of a Shandong colliery was carried out with MTS815 servo-controlled rock mechanical test system; the creep model and failure characteristics were analyzed. The experimental results indicate that the coal＇ creep threshold coefficient is 0.915 and its rheological coefficient is 0.383; rheological failure of coal presents spatial inhomogeneity, plastic destroying is mostly as a whole but dominant failure plane orientation is sheared failure; mirco-ruptures occur in the rheological process of coal which is damage; and furthermore those damages occur on lower stress levels, just the accumulation and transfixion of lots of micro-ruptures induce the failure of coal sample; both damage and hardening exist in coal creep, the creep process lies on those two mechanisms; three polynomial experiential model can describe creep characteristics of this coal compatibly; and Nishihara model can describe its initial creep stage and steady creep stage, but not accelerating creep stage.

关 键 词：煤岩 短时蠕变试验 破坏特征 微破裂 蠕变模型 

分 类 号：TD315[矿业工程—矿井建设]