ASCE has honored Beena Ajmera, Ph.D., P.E., M.ASCE, with the 2020 Collingwood Prize for the paper “Characterization of the Reduction in Undrained Shear Strength in Fine-Grained Soils Due to Cyclic Loading,” Journal of Geotechnical and Geoenvironmental Engineering, May 2019.
The author’s paper provides the first comprehensive and systematic study that yields relationships to estimate the strength loss in fine-grained soils through an extensive laboratory testing program on laboratory-controlled soil samples with a wide range of properties. The results obtained are further validated with natural soil samples from around the world. The study shows that the back-calculated postcyclic undrained strength ratios were approximately four times lower than the measured values and that based on the clay mineralogy, the arbitrarily selected degradations either underestimate or overestimate the available postcyclic strength. In doing this, the paper addresses a significant gap in our understanding and provides our community with a novel, practical and time-sensitive method of addressing strength losses in fine-grained soils as a result of cyclic loading.
The Collingwood Prize is awarded to the author or authors, under 35 years of age, of a paper describing an engineering project with which the author is directly connected, or recording investigations contributing to engineering knowledge to which the author has contributed some essential contributions and which contains a rational digest of results.