View Important Policies and System Requirements for this course

Interested in registering 5 or more engineers for a course? Contact us for information and rates.

INSTRUCTOR:  Naresh Samtani, Ph.D., P.E., D.GE, F.ASCE

Purpose and Background

Deep foundations are designed to transfer load through unsuitable subsurface layers to suitable bearing strata. One of the key advantages of deep foundations is their ability to withstand significant lateral loads. When deep foundations are installed through a soil deposit undergoing consolidation, the resulting relative downward movement of the soil around piles induces "downdrag" forces on the piles. If embankments are placed adjacent to deep foundations, as in the case of bridge abutments, “lateral squeeze” effects can induce significant unbalanced lateral forces on deep foundations. In the case of loose collapse-susceptible soils, the moisture-induced soil collapse can have a significant lateral effect on deep foundations. Seismic events can generate lateral spread and liquefaction related ground deformations. Adjacent excavations can induce differential lateral forces on deep foundations. This workshop presents the lateral analysis of deep foundations and methods to evaluate various induced ground deformations in deep foundation designs. The presentation will be based on latest (2020) version of the Bridge Design Specifications (BDS) based on the Load and Resistance Factor Design (LRFD) platform of the American Association of State Highway and Transportation Officials which is a key component of Federal Highway Administration (FHWA) guidelines for deep foundations. Information from AASHTO’s latest (2020) guide specification for Service life design will also be presented.

Benefits and Learning Outcomes

Benefits

• Understand the principles of lateral analysis of deep foundations
• Be able to define ground induced deformations and mechanisms
• Understand how to consider ground induced deformations in deep foundation designs
• Understand interaction of various ground induced deformations on deep foundation designs
• Phrase and consider the effects of induced ground deformation in context of LRFD
• Examine the possibilities and benefits of improved communications between geotechnical and structural specialists for deep foundation design

Learning Outcomes

Upon completion of this course, you will be able to:

• Explain lateral analysis of deep foundations using LRFD principles
• Explain the mechanisms for ground induced deformations
• Quantify the effects of ground induced deformations on deep foundations
• Discuss and understand the effects of subsurface stresses and deformations on existing structures

Assessment of Learning Outcomes

Achievement of the learning outcomes will be assessed through, homework, class discussion,  a short post-test (true-false, multiple choice and fill in the blank questions).

Who Should Attend?

• Geotechnical and structural specialists
• General civil engineering specialists
• Agencies/owners
• General Contractors

Outline

Using a collaborative and interactive learning approach, this virtual workshop will help you understand: (a) principles of lateral analysis of deep foundations, and (b) the types and effects of induced ground deformations on deep foundations. The workshop will help you assimilate the crucial considerations regarding these topics through active participation by frequent interactions throughout the workshop and real-time expert feedback. The interactions will facilitate a better understanding of the nuances of the various design procedures for deep foundations which would help you avoid costly design errors in real-world projects. In between the two live sessions, attendees will independently work on an application (e.g., exercises) or a reflection (e.g., reading) assignment.

DAY 1

• Loads and limit states
• Soil-structure interaction model
• Structural and geotechnical elements
• Example problem
• Equivalent cantilever model
• Steps for lateral load analysis
• Extreme Events
• Special considerations
• Review of Day 1
• Interactive Question and Answer (Q&A) session
• Assignment of homework

DAY 2

• Roadmap for Day 2
• Review of homework
• General concepts and terminology for induced ground deformations
• Downdrag and drag load
• Moisture-induced collapse of soils
• Lateral squeeze
• Lateral spread
• Excavation-induced effects
• Summary and comments
• Closure and references
• Review of Day 2 and full workshop
• Interactive Question and Answer (Q&A) session

How to Earn your CEUs/PDHs and Receive Your Certificate of Completion

This course is worth .4 CEUs/4 PDHs. To receive your certificate of completion, you will need to complete a short on-line post-test and receive a passing score of 70% or higher within 30 days of the course.