FINE DISCRETE ELEMENT SIMULATION ON THE RESISTANCE MECHANISM OF CEMENT-STABILIZED SAND

The mechanical behavior on the cementation interface is extremely important to the strength of cement-stabilized organic-matter-disseminated sand (OMDS). While a new parallel cementation model with the respect of the anti-rotation factor is used, a fine discrete element simulation model, which is called “two elements, three types of contact, and five groups of bearing forces”, is proposed. Through simulation of the unconfined compressive strength test and static triaxial test of cement-stabilized OMDS, the interfacial mechanical mechanism of enhanced strength is revealed. The development mechanism of interface damage behavior under different loading conditions is clarified. The results show that the hydrated lime can improve the contact interface between sand particles and sand particles, the cementation interface between sand particles and cemented particles. And then the friction and cohesion of the contact interface can be increased to enhance the strength of cement-stabilized OMDS. On the condition of lateral constraint, the bonded contact continues to be destroyed, while the relative slip and rotation between particle components are intensified and the friction between sand particles increases.