THE ELASTIC MODULI OF SOILS WITH DISPERESED OVERSIZE PARTICLES
To calculate the elastic deformations experienced by soils subjected to static or dynamic loads, knowledge of the elastic constants is required. The elastic constants (poisson's ratio, E, G) are normally evaluated in the laboratory using conventional triaxial compressive tests on cylindrical samples. For meaningful test results, it is necessary to maintain a ratio of sample diameter to the maximum particle size of approximately 6 to 1 or greater. However, some soils have large and dispersed oversize particles that make it impossible for them to be tested in the conventional triaxial apparatus. This study presents the application of theoretical models that calculate the elastic properties of a composite made of an elastic matrix containing large dispersed particles.
The presented models require only knowledge of the elastic properties of the matrix coupled with the concentration by volume of the large particles in order to calculate the elastic properties of the mixture. These models were applied to different mixtures under different conditions of vertical pressure and moisture content. It was found that the models predict very well the measured elastic properties. The measurement of the elastic properties was carried out using an ultrasonic velocity apparatus.
It should be noticed that most of the tests presented in this research are related to the dynamic elastic properties of the mixtures; however, it was found that most of these models could be applied in order to predict the static elastic properties too.
Advisor:Chao Lin Chiu; Jeen Shang Lin; Luis E. Vallejo
School:University of Pittsburgh
School Location:USA - Pennsylvania
Source Type:Master's Thesis
Keywords:civil and environmental engineering
Date of Publication:12/02/2002