Training Update

by Heather Shelsta

Shaking Up Geotechnical Training Delivery

On February 9, 1971, a magnitude 6.6 earthquake rocked the San Fernando Valley in southern California and wreaked havoc on the area’s transportation infrastructure, causing an estimated $505 million in property damage. Following the earthquake, the highway community expended significant effort to develop comprehensive guidelines for the seismic design of bridges. That effort led to updates of both the American Association of State Highway and Transportation Officials’ (AASHTO) and California Department of Transportation’s design provisions. A number of guidelines and specifications have been published in the decades since, with updates occurring as often as every year or two.

To help highway and bridge designers and engineers stay current with the latest seismic techniques, the National Highway Institute (NHI) offers the 5-day Load and Resistance Factor Design (LRFD)-based course 132094 LRFD Seismic Analysis and Design of Transportation Structures, Features, and Foundations. In addition, NHI recently developed two shorter, 2-day courses as an alternative for those who prefer more flexibility in scheduling. These courses are 132094A LRFD Seismic Analysis and Design of Transportation Geotechnical Features and 132094B LRFD Seismic Analysis and Design of Structural Foundations and Earth Retaining Structures.

Course Highlights

Course 132094A LRFD Seismic Analysis and Design of Transportation Geotechnical Features addresses the earthquake engineering aspects of the original course. This comprehensive training covers seismic analysis and design of geotechnical features for transportation including ground motion characterization, site characterization, and identification of geotechnical seismic hazards. The course also includes analysis procedures for liquefaction and liquefaction-induced lateral spread or flow failures, seismic settlement analysis, and geotechnical hazard mitigation measures.

Course 132094B LRFD Seismic Analysis and Design of Structural Foundations and Earth Retaining Structures focuses on the seismic design of retaining walls and structural foundations. The course covers seismic analysis and design of geotechnical features for transportation including the interaction of soil, foundation, and structure; shallow and deep foundation design; and design of earth retaining structures such as free-standing retaining walls and abutment walls. The course also discusses interactions between geotechnical specialists and bridge design engineers in the seismic design process.

The 1989 Loma Prieta earthquake damaged these concrete lane separators on California’s Highway 17 and caused the landslide visible in the background. NHI’s geotechnical training helps participants understand the risk factors and describes the latest structural technologies that can minimize damage.

NHI developed these courses using the requirements and recommendations in AASHTO’s LRFD Bridge Design Specifications and Guide Specifications for LRFD Seismic Bridge Design; the final report from National Cooperative Highway Research Program Project 12-70 Seismic Analysis and Design of Retaining Walls, Buried Structures, Slopes, and Embankments; and the Federal Highway Administration’s Seismic Retrofitting Manual for Highway Structures (FHWA-HRT-06-032 [Part 1] and FHWA-HRT-05-067 [Part2]).

A Resource for All Levels

Courses 132094A and 132094B are intended to engage an audience of bridge and geotechnical engineers with up to 20 years of experience, including those with little or no experience. Instruction methods include presentations, discussions, question-and-answer sessions, group activities, and hands-on exercises. At the end, participants undertake a group design exercise to reinforce learning and enhance the transfer of new skills and knowledge to the workplace.

Course participants gain a better understanding of the basis and limitations of the seismic design methods. They learn the practical skills needed to meet AASHTO’s performance criteria for seismic design, such as assessment of site conditions, knowledge of key soil properties necessary for seismic analysis, and methods for evaluating those properties.

The prerequisite for both courses is the 4-hour, Web-based training 132010A Earthquake Engineering Fundamentals. The prerequisite consists of six lessons: Earthquake Fundamentals, Introduction to LRFD Seismic Design, Earthquake Ground Motions, Seismic Hazard Analysis, AASHTO Design Ground Motion Characterization, and Introduction to Geotechnical Hazards.

For more information, visit NHI’s Web site at www.nhi.fhwa.dot.gov. To register for a session or to sign up to receive email alerts when sessions are scheduled, visit the course description page.

Heather Shelsta is the geotechnical training program manager for NHI.