| Journal Title /掲載ジャーナル名 |
Canadian Geotechnical Journal |
| Publication Year and Month /掲載年月 |
November, 2022 |
| Paper Title /論文タイトル |
Experimental study on swelling pressure of low dry density compacted bentonites during saturation combining X-ray diffraction |
| DOI /論文DOI |
10.1139/cgj-2020-0342 |
| Author of Waseda University /本学の著者 |
RUAN Kunlin(4th Year Doctoral Student, Faculty of Science and Engineering):First Author, Corresponding Author |
| Related Websites /関連Web |
– |
| Abstract /抄録 |
A multi-ring and a newly developed swelling pressure apparatus were adopted for measuring swelling pressure during saturation of three low dry density bentonites (sodium type: MX-80 and Kunigel-V1; calcium type: Kunibond). Subsequently, slices from the multi-ring were observed using X-ray diffraction (XRD) tests to detect basal spacing changes. Distance between particles was calculated from basal spacing database. Relations between microstructural changes, including basal spacing and distance between particles, and swelling pressure are discussed. Results show that calcium type bentonite has greater swelling pressure than sodium type bentonites during saturation. When bentonites have the same cation type, lower montmorillonite content bentonite obtains smaller swelling pressures than those of high montmorillonite content ones. Basal spacing increases drastically first, then maintains a stable value during saturation. All three bentonites gradually reach 3 w state along with wetting (MX-80 and Kunigel-V1: 1-3 w; Kunibond: 2-3 w). The distance between particles increases with the saturation time. During saturation, swelling pressure generally rises with increasing basal spacing and increasing distance between particles. The mechanism for swelling pressure development is discussed. |
