ASCE has honored David S. Yang, Ph.D., P.E., G.E., M.ASCE, with the 2019 Martin S. Kapp Foundation Engineering Award for his contributions to Deep Soil Mixing, including the beneficial expansion of its use for containment and reinforcement applications. He has truly advanced the practice and was instrumental in overcoming the obstacles needed to bring this technology to North America.
Yang has devoted more than 30 years of his geotechnical engineering career to the introduction, consultation, and implementation of Deep Mixing Method (DMM; or Deep Soil Mixing, DSM) and other soil-mixing technologies in the United States and overseas.
He has been involved in many Cement Deep Soil Mixing (CDSM) projects, that method being one of the Deep Mixing Methods used in many dams, including Sunset North Basin Dam and Perris Dam. In Sunset North Basin Dam, California, Yang proposed the cell type of improved ground to achieve liquefaction prevention and reinforcement of foundation ground. The cell-type ground improvement technique for liquefaction mitigation used on this project was the first attempt approved by Division of Safety of Dam, California Department of Water Resources. In Perris Dam projects, Yang also proposed the cell type of CDSM to achieve both liquefaction prevention and reinforcement of dam slope, economically. During construction, he carried out an extensive series of laboratory mix tests to obtain the appropriate cement dosage for the design strength. A very stiff layer was found at the site, which can cause difficulty in the construction of CDSM. In order to overcome the stiff layer, he performed a series of field tests where the construction sequence including predrilling and CDSM mixing was developed.
The Martin S. Kapp Foundation Engineering Award recognizes contributions to design or construction of foundations, earthworks, retaining structures, or underground construction. Emphasis is placed on constructed works in which serious difficulties were overcome or substantial economies were achieved.