文献类型：期刊文献

英文题名：Mechanical properties and microscopic characterization of cement stabilized calcareous sand modified by nano SiO2

作者：Luo, Jiale[1,2];Zhou, Aizhao[3];Li, Na[1];Wang, Wei[1,4];Hu, Jun[4,5]

机构：[1]Shaoxing Univ, Sch Civil Engn, Shaoxing 312000, Zhejiang, Peoples R China;[2]Shaoxing Key Lab Interact Soft Soil Fdn & Bldg Str, Shaoxing 312000, Zhejiang, Peoples R China;[3]Jiangsu Univ Sci & Technol, Sch Civil & Architecture Engn, Zhenjiang 212003, Peoples R China;[4]Natl Univ Singapore, Dept Civil & Environm Engn, Singapore 117576, Singapore;[5]Hainan Univ, Coll Civil Engn & Architecture, Haikou 570228, Peoples R China

年份：2022

卷号：17

外文期刊名：CASE STUDIES IN CONSTRUCTION MATERIALS

收录：SCI-EXPANDED(收录号：WOS:000891865000003)、、EI(收录号：20224613103028)、Scopus(收录号：2-s2.0-85141535971)、WOS

基金：Acknowledgments Thanks are due to Yitong Shou and Chenjun Wang for assistance with the experiments.This research was funded by the National Natural Science Foundation of China (Grant no: 52179107) .

语种：英文

外文关键词：Calcareous sand; Unconfined compressive strength; Splitting tensile strength; One-dimensional consolidation; Scanning electron microscope test

外文摘要：The accessible crushing property of calcareous sand leads to poor mechanical properties. Cement is usually used for solidification treatment in engineering. Nano-SiO2 (NS) can further improve the strength of cement-stabilized calcareous sand (CCS). In this study, the mechanical research of NS modified CCS is carried out through unconfined compression strength (UCS) test, split tensile strength (STS) test, and one-dimensional consolidation (ODC) test. The results show that when the CCS was solidified with 4.5 parts per thousand NS, the unconfined compressive strength reaches the maximum after 7-14 days of solidification, and the strengthening effect of NS is reflected in the early hy-dration stage. The addition of NS increased the splitting tensile strength at 7 days and 14 days by 100% and 48%,respectively. The ratio of splitting tensile strength to unconfined compressive strength was about 0.11, which was consistent with the curing law of solidified soil. Moreover, the addition of NS can reduce the compression coefficient of the sample, improve the compression modulus, and improve the compressive deformation resistance of CCS. The scanning electron microscopy (SEM) was used to study the microscopic mechanism. SEM test showed that the addition of NS produced more needle-like hydrates, and the nucleation effect of NS made the hydrates more tightly cemented. The porosity was obtained after the binary processing of SEM images, and the relationship model between the microstructure parameter porosity and UCS was established.