摘要
针对原状红砂岩具有自由膨胀率为 3.5 %、而膨胀力高达 270 kPa、干燥岩样峰值强度为 5.85 MPa、饱和岩样抗压强度仅为 0.20 MPa 等这些特殊性质的膨胀岩,采用 MTS815.02 型岩石力学刚性伺服试验机与自行研制的岩石膨胀测量仪,进行了不同含水率红砂岩膨胀变形性质试验。结果表明:(1) 在低荷载状态下,红砂岩膨胀应变随着含水率增加而呈对数形增长;(2) 在高荷载作用下,红砂岩膨胀应变与吸水率之间存在着线性关系;(3) 红砂岩吸水膨胀应变在较短的时间内基本完成,随着时间的延长,膨胀变形将趋于稳定。在此基础上,提出了确定膨胀稳定时间的理想概化数学模型。研究成果对南京红山窑水利工程膨胀岩地基处理方案设计、施工具有重要的指导意义。
For the reason of special expansive characteristics of red sandstone, a series of experimental procedures performed in rock mechanics rigidity servo testing system (RMTS815.02) and rock oedometer, developed to determine the swelling behaviour of red sandstone taken from a foundation pit of Hongshanyao Project (HSYP) in Nanjing, are described. Based on the experimental data, an empirical formula of expansive strain with water content was expressed as Ε = aln(w+1) + b. It is clear that the curve of expansive strain-water content is a logarithm. In the meantime, the relation of expansive strain with time was studied and the importance of expansive stabilization time was illuminated. The experimental results indicated that the water content has a tremendous effect on peak expansive and steady expansive deformation of swelling red sandstone; and it must be a momentous guide in the engineering design and construction.
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2004年第7期1041-1044,共4页
Rock and Soil Mechanics
基金
中科院武汉岩土力学研究所岩土力学国家重点开放科学基金项目(Z110306)
河海大学科技创新基金项目(2001401743)
关键词
红砂岩
膨胀变形
含水率
试验
Deformation
Rock mechanics
Strain
Swelling
Water
