水泥基材料孔隙结构随机分散模型与仿真试验

Random Dispersion Model and Simulation of Model Pore Structure of Cementitious Materials

为描述水泥基材料的孔隙结构演变,将水泥浆体看作两相介质随机分散体系,建立了孔隙结构计算模型.同时采用μic平台进行水泥水化仿真,与理论结果相互验证,并进一步分析理论模型的计算条件和参数变化规律.计算结果表明:对于完全分散的新拌水泥浆体,多分散硬球模型与仿真结果一致;考虑水化产物交错和团聚效应,单分散同心球模型计算的孔隙结构与仿真结果一致,且硬核半径比与水化度呈线性负相关.考虑水泥颗粒絮凝效应时,单分散硬球模型与仿真结果接近.

In order to investigate the evolution of pore structures in cementitious materials,a statistical model is proposed by taking the cement paste as a random dispersion system of two-phase medium.Simultaneously,theμic platform is employed to simulate the cement hydration.The results obtained from the simulation and the disperse models are compared with each other,and further analysis on calculation conditions and parameters of the disperse models are conducted.The pore size distribution obtained from polydisperse hard sphere model is very close to the simulation in completely dispersion condition.Taking into account the cross and agglomeration effects of hydrated products,the calculation results of the monodisperse concentric-shell model are more consistent to the simulations.Considering the flocculation of cement particles in initial state,the monodisperse hard model is closer to the simulation results.This paper offers a new insight from the viewpoints of mathematics and physics to understand and describe the pore structures of cementitious materials.