EFFECT OF PARTICLE CONTACT BOND ON SHEAR MODULUS

The resonant column technique is used to identify the most significant factors affecting the low-strain shear modulus of sand cemented with various types of cementing materials. Results show that the increase of low-strain shear modulus of cemented sand greatly depends on the number of contact points between soil particles at which bonds are developed by the cementing materials. The writers conclude that the effective grain size D10 and coefficient of uniformity C(u) are the most important index properties of soil controlling the number of interparticle contacts in sand. In addition, the cementation level, which is expressed in terms of percent void filled by cementation, and properties of cementing material also significantly affect the shear modulus of cemented sand. Results indicate that well-graded sand with small effective grain size can be significantly improved in stiffness by cementation because of its grain number of contact points between soil particles. An empirical equation is developed for quantitatively estimating low-strain shear modulus of cemented sand.