The Search for Internal Stability in Reinforced Soil
Tóm tắt
Professor Jonathan Wu’s career was devoted to rigorous development of internal stability in reinforced soil as a new and evolving technology. This paper presents two of Professor Wu’s students’ work on the search for internal stability by tracing his work. Engineering design of reinforced soil originated in France with Schlosser and Vidal in the late 1960s. The first designs were based on a simple limit state method. Analyzing test data, Schlosser later found that the limit method was insufficient and that internal stability involves stiffness. Wu found that stiffness was affected by reinforcement spacing. Settlement or collapse is shown in examples that violate this spacing criterion. Initial analysis and validation involved geosynthetic sheets, but these were extended to other materials and to strip reinforcement. The analysis has been validated both by laboratory data and by field observations. These findings corroborate those of international companies in the reinforced soil community, but they are often incompatible with code in North America. The studies and discussions presented in this paper are further enhanced with the most current testing and work to confirm Professor’s Wu insights and visions.
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