STM Example: Reinforced Concrete Corbel

Adisorn O.
4 days ago
2 min read

Here we show the real example of reinforced concrete corbel to carry a total load of 900 kN, i.e. 4 points of 225 kN. The STM model is treated as 2D model with 400 mm thick using CAST software,

The stress at nodal zones are analyzed and listed as following. It shows that forces are safely transferred through nodes.

The stresses for each strut are also summarized as shown below.

Hint to model STM:

The Load Path Method (El-Metwally and Chen, 2017, p. 28)

The development of an STM using the load path method is illustrated in the following steps (Schäfer and Schlaich, 1998, and Schlaich and Schäfer, 1993) with reference to the two examples in Figures 2.1 and 2.2.

1.The boundary forces acting on a D-region from the attached B-regions or supports or external forces should be determined, as illustrated for the D-regions in Figures 2.1a and 2.2a.

2.Subdivide the stress diagrams to match with opposite forces. Locate the resultants of the subdivided stress diagrams in their center of gravity, Figures 2.1b and 2.2b.

3.Connect the opposite forces by streamlined load paths which are straight or smoothly curved, Figures 2.1b and 2.2b:

•Start in the direction of load

•Avoid crossings with other load paths

•Choose curvature near discontinuities of load or geometry as large as possible

4.Indicate deviation forces as a basis for transverse struts and ties, Figures 2.1b and 2.2b.

5.Replace the curved load paths by polygons with kinks (bends) at the points of largest curvature or the estimated location of the deviation force resultant, Figures 2.1c and 2.2c. In the model, dashed lines indicate struts and solid lines indicate ties.

6.Connect the remaining stress diagrams by loop-shaped load paths.

7.Extend the ties (reinforcement) preferably straight as far as needed to meet and balance the transverse forces of primary load paths.

Reference:

El-Metwally, S. and Chen, W.-F. (2017) Structural Concrete. 1st edn. CRC Press. Available at: https://www.perlego.com/book/1507553 (Accessed: 2 June 2025).