Fractal Theory Used in Pore Structure of Cement-Based Materials Incorporated Phosphorus Slag

Abstract

Based on fractal theory and MIP data of cement stone incorporated phosphorus slag, pore volume fractal dimensions (D) were calculated, and the relationship between D and several factors were explored. Results shown: pore structure of cement stone incorporated phosphorus slag has obvious fractal characteristics, D was between 2.887 ~ 3.936. D was an important parameter to quantitatively characterize fractal characteristics, distribution of pore was more complicated when D became larger. D reduced with increased of phosphorus slag content at early, The increase of content under 50% can promote the decline of amount and diameter of pore at later. D increases with the growth of age before 90d, but at 90 d, D get lower. Spatial distribution of cement paste was more uniform when phosphorus slag became finer. Compared with singly incorporated fly ash, incorporated phosphorus slag and fly ash at the same time can further reduce D, which is the superiority of that.In recent years，with the developing of fracture mechanics and fractal theory, scholars have found that pore structure of some porous materials has obvious fractal characteristics, and D can be used to descript microporous structure and related properties such as physical and chemistry [1]～[3] . And the concept of fractal began to be applied to hole structure of hardened cement paste [4] , fractal dimension of pore area or volume was used to evaluate surface roughness and volume spatial distribution. Using related knowledge of fractal theory and MIP data, paper studied pores fractal characteristics of cement hydration products incorporated phosphorus slag, calculated pore volume D of different products, and analyzed the relationship between D and age, phosphorus slag content and specific surface area.

Influence of Phosphorus Slag on Physical and Mechanical Properties of Cement Mortars

“…The steam-curing condition has been believed to be capable to repair retardations of phosphorus slag [26]. Mechanisms of phosphorus slag on the porosity of blended pastes are studied by transformations of cement hydrates [27] and the fractal theory [28]. Effects of phosphorus slag on mechanical strength and chemical shrinkage are briefly discussed by models along with comparisons to cement pastes with GGBS [29,30].…”