【摘要】：土體剪切帶的產生和發(fā)展是巖土工程界一直關注的問題。對千枚巖碎屑土進行了固結排水剪切試驗,并在試驗過程中采用CT可視化技術進行了實時監(jiān)測掃描,得到同一斷面位置不同應變條件下的系列CT切片,從CT切片中可觀測到試樣隨應變的增加而出現的明顯的剪切帶。采用CT技術真實再現了三軸試樣在軸向力作用下,局部裂紋擴展逐漸貫穿形成完整剪切帶的過程。對CT切片進行了7個區(qū)域的CT數平均值和CT數標準差統(tǒng)計,分析認為,軸向應變在3%~10%范圍內是剪切帶形成和發(fā)展的主要階段,在應變3%前試樣主要被壓縮,在應變3%后試樣在偏應力的作用下逐漸出現微裂隙,并隨應變的增加,微裂隙越來越明顯。CT數統(tǒng)計值出現微裂隙的應變和宏觀觀測到微裂隙的應變不對等,在判斷剪切帶微裂隙出現應變上建議以CT數統(tǒng)計值為準值。
[Abstract]:The generation and development of soil shear zone has been concerned by geotechnical engineering. The consolidation drainage shear test of thousands of rock clastic soils was carried out, and the real-time monitoring and scanning was carried out by using CT visualization technology, and a series of CT slices under different strain conditions in the same section position were obtained. The obvious shear band of the sample with the increase of strain can be observed from the CT slice. CT technique is used to reproduce the process of local crack propagation through the formation of complete shear band in triaxial specimens under axial force. The average value of CT number and the standard deviation of CT number in seven regions of CT slices are counted. It is considered that the axial strain in the range of 3% 鈮，

本文編號：2492725