Effect of molding process on the performance of cement stabilized gravel.

In order to study the effects of molding process on the macroscopic performances of cement stabilized gravel, based on two kinds of gradation of skeleton compaction and suspension compaction, eight kinds of cement stabilized gravel were prepared by four kinds of processes: static compaction molding with forced mixing, vibratory compaction with forced mixing, static compaction molding with vibratory mixing, and vibratory compaction with vibratory mixing. Furthermore, the macro-performances of cement stabilized gravel were investigated by adopting the 7 d unconfined compression test, the 28 d single-axis penetration test, the 7 d warming shrinkage test, and the 7 d drying shrinkage test. The underlying microscopic mechanism of the macroscopic property variation of the cement stabilized gravel was analyzed by combining with the microscopic means of scanning electron microscope. The results show that the mechanical properties of cement stabilized gravel with skeleton dense grading under vibration mixing and vibration compaction process are optimal, and its 7 d unconfined compressive strength and 28 d uniaxial compression modulus are improved by 169. 5% and 97. 2%, respectively, compared with that of forced mixing and static compression molding. The vibration mixing vibration compaction techniques can improve the macro performance of cement stabilized crushed stone in terms of promoted the cement hydration product generation, perfect structure, and elevated overall uniformity. [ABSTRACT FROM AUTHOR]