岩土力学
巖土力學
암토역학
ROCK AND SOIL MECHANICS
2013年
5期
1319-1324
,共6页
方祥位%申春妮%汪龙%陈正汉%成培江
方祥位%申春妮%汪龍%陳正漢%成培江
방상위%신춘니%왕룡%진정한%성배강
Q2黄土%浸水%微观结构%湿陷性
Q2黃土%浸水%微觀結構%濕陷性
Q2황토%침수%미관결구%습함성
Q2 loess%wetting%microstructure%collapsibility
对陕西蒲城电厂 Q2黄土浸水前后的试样进行微观结构对比测试,得到了大量珍贵的微观结构图片.浸水前后 Q2黄土的微观结构定性、定量分析表明:架空孔隙受力作用影响较大,对水的作用敏感;粒间孔隙对压力和水的作用相对较迟钝;Q2黄土的湿陷峰值压力大于200 kPa.随着压力的增大,Q2黄土的灰度熵、欧拉数和孔隙的面积比例、圆形度、定向度、分布分维减小;而颗粒的面积比例、圆形度、定向度、分布分维将增大;随着水的浸入,各量将继续减小或增大;浸水后孔径大于20mm的孔隙含量减少,孔径小于20mm的孔隙含量增加,湿陷的过程中大部分孔隙都在发生变化,大孔隙变成中、小孔隙,中、小孔隙则变为更小的孔隙.浸水前后微观结构的变化能较好地解释Q2黄土特殊的湿陷性.
對陝西蒲城電廠 Q2黃土浸水前後的試樣進行微觀結構對比測試,得到瞭大量珍貴的微觀結構圖片.浸水前後 Q2黃土的微觀結構定性、定量分析錶明:架空孔隙受力作用影響較大,對水的作用敏感;粒間孔隙對壓力和水的作用相對較遲鈍;Q2黃土的濕陷峰值壓力大于200 kPa.隨著壓力的增大,Q2黃土的灰度熵、歐拉數和孔隙的麵積比例、圓形度、定嚮度、分佈分維減小;而顆粒的麵積比例、圓形度、定嚮度、分佈分維將增大;隨著水的浸入,各量將繼續減小或增大;浸水後孔徑大于20mm的孔隙含量減少,孔徑小于20mm的孔隙含量增加,濕陷的過程中大部分孔隙都在髮生變化,大孔隙變成中、小孔隙,中、小孔隙則變為更小的孔隙.浸水前後微觀結構的變化能較好地解釋Q2黃土特殊的濕陷性.
대협서포성전엄 Q2황토침수전후적시양진행미관결구대비측시,득도료대량진귀적미관결구도편.침수전후 Q2황토적미관결구정성、정량분석표명:가공공극수력작용영향교대,대수적작용민감;립간공극대압력화수적작용상대교지둔;Q2황토적습함봉치압력대우200 kPa.수착압력적증대,Q2황토적회도적、구랍수화공극적면적비례、원형도、정향도、분포분유감소;이과립적면적비례、원형도、정향도、분포분유장증대;수착수적침입,각량장계속감소혹증대;침수후공경대우20mm적공극함량감소,공경소우20mm적공극함량증가,습함적과정중대부분공극도재발생변화,대공극변성중、소공극,중、소공극칙변위경소적공극.침수전후미관결구적변화능교호지해석Q2황토특수적습함성.
@@@@The microstructure changes of Q2 loess in Pucheng power plant, Shaanxi province before and after wetting are studied by using Quanta ESEM (environment scanning electron microscope). A lot of microstructure pictures are obtained. The microstructure qualitative analysis results of Q2 loess before and after wetting with different pressures show that the intra-particle pores are more sensible to pressure and water than inter-particle pores. The maximum pressure of collapsibility of Q2 loess is more than 200 kPa. The area proportion, the roundness, the orientation and the distribution fractal dimension of pore, the gray entropy, the Euler value decrease with increase of pressure and wetting; however, the area proportion, the roundness, the orientation and the distribution fractal dimension of particle increase with pressure and wetting. The quantities of pores with diameter greater than 20 mm during wetting;while the quantities of pores with diameter less than 20mm the pore content increases during wetting. Most pores change during wetting;the large pores turn into medium and small pores;the medium and small pores turn into smaller pores. The peculiar collapsibility of Q2 loess can be explained well by the microstructure changes of Q2 loess before and after wetting with different pressures. The microstructure qualitative analysis provides a new method to research the mechanisms of collapsibility of loess.