Effect of Curing Periods on the Strength and Microstructures of Cement-stabilized Soils Mixed with Composite Recycled Materials
古川, 芹菜亀井, 健史
22 , 2016-07-31 , 宮崎大学工学部
This paper describes the effect of curing periods on strength-deformation characteristics of cement-stabilized soils mixed with composite recycled materials. The strengths of samples were determined by unconfined compression tests after 3, 7, 14 and 28 days of curing immediately following molding. The effects of curing periods and composite recycled materials content on stress-strain behavior of cement-stabilized soils are quantified. Addition of 10, 20 and 40 % composite recycled materials to the soil increases the shear strength of cement-stabilized soil at short curing periods ( 3 and 7 days), compared to cement-stabilized soil with no composite recycled materials. This contribution of composite recycled materials at an early stage of curing is significant for improvement of trafficability and the reduction of construction period for soft soil. The unconfined compressive strength increases with increase in composite recycled materials contents. This is due to concomitant decrease in the water content and increase in the dry density. The test results also show that the admixture in the present study has a significant effect on the production of ettringite. Based on the observation of internal structure using a scanning electron microscope (SEM), ettringite occurrence is related to the strength increase of cement-stabilized soil.