การศึกษาพฤติกรรมด้านกำลังเนื่องจากผลกระทบของอุณหภูมิและอัตราของดินเหนียวปากพนัง

Abstract

Changes in soil engineering behavior because of the changing temperature affect the strength of the soil, especially saturated clay. The total ground response depends on time-dependent behavior or viscosity of soil, especially in clay. To predict soil behavior and design structure foundation, the engineer must clearly understand the time-dependent behavior of dependent behavior is the result of the viscosity of soil that relates to the plasticity of soil that viscosity of so is predominant in clay. Pakphanang, Nakhon Si Thammarat province rapidly developing city, eastern coast of southern of Thailand. The geology of Pakphanang is soft marine clay that is a potential host formation for geothermal utilization. Therefore this research aimed to present stress-strain behavior and shear strength of soft Pakpanang clay by developed triaxial compression apparatus at varying of temperature and shear rate. Triaxial tests, consolidated undrained type. The shear temperature were 45 and 60 degrees Celsius, shear rates were 0.02%, 0.075%, 1.0%, and 6.0% per minute. At the end of this paper, we will present a comparative study of the relationship between stress and strain, shear strength of soft clay, high temperature, and room temperature. The test results were showed that the increased temperature did not affect molecular structure of soil but it's was effect to Atterberg's limits. The dried soils have plastic limit (PL) of 36.9 percent, liquid limit (LL) of 109.0 percent, and 72.1. of plastic index (PI). The soil that dried by heat the liquid limit is 70.7 percent, plastic limit is 31.0 percent. It's showed that Pakphanang Clay is organic clay. In addition, increased temperatures also contribute to the strength of Pakphanang clay, the strength of the clay is increased in every overconsolidation ratio, a few moving to the point of failure, The soil at room temperature reaches to the point of failure about 12.1 percent of the axial strain. The soil at 45 and 60 degrees Celsius had a failure point about 8.3 and 6.2 percent of the axial strain, respectively. The temperature also contributes to the modulus of elasticity at the point of failure, a clear increase in the modulus of elasticity secant, no significant effect of excess water