Characteristics and causes of the preconsolidation stress of soils in the Yellow River Delta |
| |
Authors: | Xiujuan Yang Yonggang Jia Hongjun Liu Hongxian Shan |
| |
Institution: | College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, P. R. China |
| |
Abstract: | Preconsolidation stress (σ′
P
) is the maximum effective stress that a soil has suffered throughout its life. From a geotechnical point of view, pre-consolidation
stress has great importance because it separates elastic and reversible deformations from inelastic and only partially irreversible
deformations and marks the starting point of high compressibility. In this study we calculated the preconsolidation stress
for 72 undisturbed soil samples from the Yellow River Delta, using the oedometer test and applying the method proposed by
Casagrande. The results showed that the over-consolidation ratio (OCR—the ratio of pre-consolidation stress to current natural
overburden stress) values of the soil from soil surface to 6m depth varied from 1.72 to 15.34 and the maximum pre-consolidation
stress was above 200 kPa. In consequence, the soils of the Yellow River Delta are highly over-consolidated within the upper
6 m, the OCR decreasing gradually with depth from 6 to 12 m. For samples from deeper than 12 m the soils were found to be
under-consolidated, which was proved by standard penetration tests (SPTs). The main causes of this type of consolidation are
the mineral composition and the designability of the soil body. |
| |
Keywords: | pre-consolidation stress Casagrande method OCR Yellow River Delta |
本文献已被 CNKI 维普 万方数据 SpringerLink 等数据库收录! |