Title:
Z-Shaped Load Path: A Unifying Approach to Developing Strut-and-Tie Models
Author(s):
Mohamed E. El-Zoughiby
Publication:
Structural Journal
Volume:
118
Issue:
3
Appears on pages(s):
35-48
Keywords:
discontinuity regions; load path; structural concrete; strutand- tie modeling; Z-shaped load path
DOI:
10.14359/51730535
Date:
5/1/2021
Abstract:
The load path approach is frequently used for laying out strut-and-tie models. In this paper, an attempt is made to simply and systematically generate strut-and-tie models for two-dimensional (2-D) and three-dimensional (3-D) disturbed or discontinuity (D) regions from load paths. A unified Z-shaped load path approach is proposed where three individual Z-block models are first identified and then later unified in a single Z-block model with/without hanger(s) reinforcement. To understand what the proposed approach is and how it works, a general “three-step procedure” or simply a “break-form-assemble” process is presented and used to regenerate the strut-and-tie models for some available problems. It involves breaking the system of the force resultants on the boundaries of D-region(s) down into parts with only two forces remaining on any part, forming the parts in Z-block models, and assembling and connecting the blocks using transverse struts and ties to obtain the whole model. Implementing the proposed approach could become the basis for either a simple hand-based or computer-aided strut-and-tie model of structural concrete from load paths.
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