2015 Peck Lecture - Bio-Stabilization of Slopes and Stream Banks

Ralph B. Peck Medal Lecture
Bio-Stabilization of Slopes and Stream Banks

The Ralph B. Peck Medal Lecture is delivered annually by a geotechnical engineer selected for outstanding contributions to the profession through the analysis and publication of case histories.

Bio-stabilization has been used successfully at scores of sites across the U.S.A. A typical feature of this approach is the use of inert materials, e.g., rock and geo-synthetics, in combination with transplants and live cuttings. The cuttings are placed in the ground in various arrays and patterns where they can provide soil reinforcement, drainage, and barriers to soil erosion or shallow earth movement. These techniques lend themselves readily to hand labor, where access is problematic, but can also be adapted to placement and installation using heavy machinery. Selected techniques will be described briefly. Microbial stabilization, using fungi and bacteria, will also be discussed. A number of case studies, e.g., highway cut slope stabilization and stream bank protection, will be described where a bio-stabilization approach was adopted. Project evaluations and lessons learned will be included.

Presented by Donald H. Gray, Professor Emeritus, University of Michigan.

Professor Gray has made major and long-standing contributions in the broader field of geoenvironmental engineering, soil behavior, and soil reinforcement. However, the field for which he is recognized as an authority worldwide, is the field of bioengineering, bio-stabilization and geomorphic modification [also known as landforming]. Throughout his career, Prof. Gray has made unique contributions as a researcher, educator and consultant in promoting engineering techniques for stabilization of earth masses that are not just environmentally friendly, but are fully integrated with the environment they are engineered in.

With the increasing recognition of the importance of sustainability, these techniques are not only becoming accepted, but are often preferred compared to the more traditional hard engineering approaches.

Professor Gray has arguably made the most contributions in these fields through the development of design methodologies based on analytical evaluations for the successful implementation of these techniques in engineering practice. This allows their performance in the field to be assessed, and the development of recommended practices based on the performance of these projects to be developed. Surely, this approach of analytical insight combined with keen observation of field performance, in addition to learning and improvement of engineering practices is in complete harmony with Prof. Ralph Peck’s own philosophy.

Don Gray has combined lessons from study and analysis of natural processes, such as stream erosion, slope failures, ground reinforcement and stabilization by vegetation and rootsystems, and the role of landforms in development of stable topographic features, with first principles to develop new ways for land preservation, for environmental protection and enhancement, and for sustainable site development for infrastructure systems. As a keen observer of the bio-mechanical processes continually at work on and in the earth he has been able to engineer new and better ways to protect, conserve and enhance our environment.

As a developer and proponent of the "observational method", Ralph Peck demonstrated by example the essential role of learning from case histories for minimizing risk and assuring success in geotechnical engineering and construction of complex projects. Don Gray, in his published papers and books, has drawn many lessons and illustrations from case histories that serve to both help define and validate the fundamentals of the bioengineering of the ground around us and the sites on which we work.

To learn more about the Geo-Institute and for membership information: http://www.asce.org/geotechnical-engineering/geo-institute/

Video Production by Magnus Media Group: http://www.magnusmediagroup.com/

Видео 2015 Peck Lecture - Bio-Stabilization of Slopes and Stream Banks канала Geo-Institute of ASCE