Abstract: The expansion mechanics behavior of soundless cracking agent (SCA) is studied by adopting the experiment and particle discrete element method.The output properties of axial stress of SCA in a cylinder with diameter of 150 mm is analyzed by experiment,the curves of axial pressure with hydration time of SCA under the two conditions of fully-constrained and reserving a free expansion space are obtained.Based on the basic theory of discrete element,the hydration expansion processes of SCA under the condition of reserving different free expansion spaces are simulated,the influence of volume expansion rate to axial stress is discussed in detail.The results show that the simulation results is basically consistent to the ones obtained by experiments,which further indicated that is is feasible to study the expansion behavior of SCA by adopting the particle discrete element method,besides that,with the increasing of volume expansion rate,the axial stress in the cylinder is decreased.

Key words: SCA, Particle discrete element method, Axial stress, Volume expansion rate