【摘要】：利用電子萬能試驗(yàn)機(jī)對四種典型塊煤開展單軸壓縮破壞實(shí)驗(yàn),研究其應(yīng)力應(yīng)變及破壞形式等力學(xué)特性.利用高速攝像儀拍攝煤塊表面細(xì)觀結(jié)構(gòu)圖像,并計算分形維數(shù)以定量描述煤塊在單軸壓力載荷下表面細(xì)觀結(jié)構(gòu),最終建立應(yīng)力與表面分形維數(shù)的關(guān)系.結(jié)果表明:煤表面和內(nèi)部存在大量孔隙、裂隙等缺陷以及其具有的不均勻性,導(dǎo)致其單軸壓縮實(shí)驗(yàn)力學(xué)特性存在各向異性特征,破壞形式主要為沿縱向主裂隙的劈裂破壞;同種煤的最大和最小的應(yīng)力強(qiáng)度值相差很大,不同煤種的力學(xué)參數(shù)也有整體的差異性.通過定義相對分形維數(shù)和相對應(yīng)力強(qiáng)度發(fā)現(xiàn)單軸壓應(yīng)力與表面分形維數(shù)呈現(xiàn)非線性增長關(guān)系.
[Abstract]:The uniaxial compression failure experiments of four typical lump coals were carried out by using electronic universal testing machine, and their mechanical properties such as stress, strain and failure form were studied. The surface meso-structure image of coal block is taken by high-speed camera, and the fractal dimension is calculated to quantitatively describe the surface meso-structure of coal block under uniaxial pressure load. finally, the relationship between stress and surface fractal dimension is established. The results show that there are a large number of pores, cracks and their inhomogeneity on the surface and interior of coal, which leads to the anisotropy of the mechanical properties of the uniaxial compression experiment, and the failure form is mainly the split failure along the longitudinal main fracture. The maximum and minimum stress intensity values of the same coal are very different, and the mechanical parameters of different coal types are also different as a whole. By defining the relative fractal dimension and the relative stress intensity, it is found that the uniaxial compressive stress has a nonlinear growth relationship with the surface fractal dimension.
【作者單位】： 華中科技大學(xué)煤燃燒國家重點(diǎn)實(shí)驗(yàn)室;
【基金】：國家自然科學(xué)基金資助項目(51576072)
【分類號】：TD31

【相似文獻(xiàn)】

相關(guān)期刊論文 前10條

1 施紹裘;張懋炯;施國勇;;斷裂表面的分形維數(shù)及其測量[J];寧波大學(xué)學(xué)報(理工版);1992年02期

2 徐龍君，張代鈞，，鮮學(xué)福;煤微孔表面的分形維數(shù)及其變化規(guī)律的研究[J];燃料化學(xué)學(xué)報;1996年01期

3 陳三強(qiáng),劉永忠,程光旭,黃昌斌;用壓汞法計算凍干物料的表面分形維數(shù)[J];食品科學(xué);2004年07期

4 景貴成,劉福海,俞理;天然低滲巖芯分形維數(shù)變化原因分析[J];巖石力學(xué)與工程學(xué)報;2005年06期

5 劉明芹;張曉光;;一種計算圖像分形維數(shù)的有效方法[J];西安科技大學(xué)學(xué)報;2009年03期

6 穆在勤,龍期威;由面積-周長關(guān)系測量的分形維數(shù)與材料韌性的關(guān)系[J];材料科學(xué)進(jìn)展;1989年02期

7 蘇輝,張玉貴,閻振h

本文編號：2490781