การวิเคราะห์โครงสร้างจุลภาคของสัดส่วนดินเม็ดละเอียดที่มีผลต่อกำลังอัดแกนเดียวของดินลูกรังผสมซีเมนต์สำหรับวัสดุชั้นรองพื้นทาง

Abstract

This thesis is the study and microstructural analysis of fine-grain soil proportions on unconfined compressive strength (qu) of lateritic soil-cement for subbase materials. The unconfined compression tests were carried out following the Department of Highway (DOH) standard. The aim of this research is to explain the development of compressive strength of Lateritic Soil-Cement by SEM (microstructure study), XRF (chemical composition study) and XRD (mineral composition study) techniques and to investigate the effects of fine contents, cement contents and curing periods of 7, 14, and 28 days. series of the fine contents of 0, 20, 30, and 40% of a dry weight and the cement contents of 0, 4, 6 and 8% of a dry soil weight were targeted.

It was found that non-stabilize sample with 20% of fine content showedthe maximum qu and dry density. The fine content with more than 20% decreases the qu in all cement contents because the product C-A-S-H compound from hydration products was decreased. The qu of 4% cement content with 20-40% of fine content can be used for the subbase materials. When the cement contents and curing times increase, the qu of cementitious products increase.

The relationship between fine content and cement content to the qu at curing periods of 7, 14, and 28 days was presented in the qu prediction equation as suggested in this study