How to Evaluate Earth Pressure for Retaining Wall Design
Webinar instructions will be emailed before the date of the webinar.
Please log into the webinar 15 – 30 minutes before start time.
Thursday, June 9, 2022
2:00 – 4:00 pm CDT
Bill Simpson, P.E.
Defining “the wall”
Identifying forces on a retaining wall
How to account for and resist soil pressure
How water pressure impacts a retaining wall
The properties of the soil that contribute to the wall design
Equations and real life examples
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2.0 HSW CE Hours
2.0 AIA LU|HSW
2.0 HSW CE Hours
2.0 LA CES HSW PDHs
International Code Council:
.2 CEUs (Sitework)
2.0 ASFPM CECs
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Completion certificates will be awarded to participants who complete this event, respond to prompts, and earn a passing score (80%) on the quiz that follows the presentation (multiple attempts allowed).
Bill Simpson P.E.
Geotechnical Structure Design Specialist at Gradelta Engineering.
Mr. Simpson founded Gradelta Engineering in 2020 with the intent to help clients better understand the combination of geotechnical and structural engineering that he has worked with for the past 20 years. He earned his B.S.C.E. and M.S.C.E. degrees from Georgia Institute of Technology. He currently provides engineering services to contractors and fellow engineers for earth structure pricing, along with the plans and calculations needed for construction. He frequently consults with clients regarding the optimal structure type and location on the construction site to minimize risk and maximize useable space. He also works in the education sector providing not just seminars such as this one, but also acting as a subject matter expert creating study guide and test prep content for the NCEES Professional Civil Engineer exam. Mr. Simpson has also worked with lawyers and insurance companies during forensic investigation and lawsuits surrounding retaining walls and slope failures. His hope is that through the instructional services that he currently provides, slopes will remain stable and retaining wall failure will be eliminated.
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Course Title: How to Evaluate Earth Pressure for Retaining Wall Design
Delivery Method: Live Online
Course Description: This two-hour live presentation identifies the forces that act upon retaining walls, how to account for and resist these pressures, the impacts of water and ice, the properties of soil that contribute to design, equations and calculations, and real life examples.
Learning Objective 1:
Learners will be able to describe the two competing theories of earth pressure, Coulomb and Rankine, and use their respective equations to understand the impact that soil and water have on a retaining wall.
Learning Objective 2:
Learners will be able to understand the resisting and driving forces of the three main types of failure modes: translation, rotation and bearing capacity.
Learning Objective 3:
Learners will be able to identify the impacts that the presence of water and ice can have on different components of a retaining wall, including at the toe, in the backfill, in front of the wall and during construction.
Learning Objective 4:
Learners will be able to describe and differentiate between different types of retaining walls, including cast-in-place concrete, rubble walls, large precast block, and MSE walls.
LUs: 2.0 LU Type: LU|HSWs.
Prerequisites: Experience with earthwork and site development
Advance Preparation: None
Program Level: Intermediate
Course Expiration Date: 04/06/2025
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Complaints regarding this course can be emailed to firstname.lastname@example.org or by calling (715) 835-5900. A HalfMoon Education representative will respond within 72 hours to resolve the complaint, which will include, but not limited to, access to another CE activity at no or reduced cost or a full or partial refund. Each instance will be resolved on a case-by-case situation.