Investigation of fracture properties of cement-treated crushed rock

Abstract

A series of parametric tests have been conducted to investigate the fracture properties of cement-treated crushed rock with four specimen curing periods (14 d, 28 d, 60 d and 90 d) and four different cement contents (4%, 5%, 6% and 7%). By means of three-point bending method, the fracture toughness, fracture energy and the ultimate deflection in span center of the specimen of cement-treated crushed rock were measured respectively. The test results indicate that the curing period and cement content of the specimen have great influence on the fracture parameters of cement-treated crushed rock. With the increase of curing period, the resistance of cement-treated crushed rock to crack spreading is improved because the fracture toughness and the fracture energy are increasing gradually. With the increase of cement content, the fracture toughness, fracture energy and the ultimate deflection in span center of the specimen are decreasing gradually. It is better to select smaller cement content for the construction of cement-treated crushed rock base layer on condition that the compressive strength of the base layer can meet demand.

Comparative analysis of dynamic load characteristics of artillery steering gear based on different MBD methods

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Non-linear micro-mechanical behavior of heterogeneous cement-stabilized macadam

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