Figure 1: Book 1 (
Information presented on this page is intended to demonstrate the section design convergence of ACI 318-2014 provisions for isolated foundations that can be achieved with SkyCiv. All examples are taken from the following references:
Book 1: David A. Fanella. Reinforced Concrete Structures Analysis and Design, 2011.
Example # 1 Design of axially loaded Combined footing.
reference: Book 1, pp.568.
DESCRIPTION
A Combined foundation is subjected to two (2) static load cases (Dead and Live). The resulting shear , moment, load transfer and development length are compared with manual calculations. The foundation model lies in the X-Z plane.
GEOMETRY AND MATERIAL PROPERTIES
Figure 2: Footing model and material properties of example #1
LOADING
Three static loads cases are considered:
For Column 1
\( \text{DL} = 300.00 \text{ kips} \)
\( \text{LL} = 115.00 \text{ kips} \)
For Column 2
\( \text{DL} =500.00 \text{ kips} \)
\( \text{LL} = 225.00 \text{ kips} \)
The results of service and factor load combination are in computed in reference of ASCE/SEI 7-10.
ANALYSIS
The analysis is done using the rigid conventional method. See the Combined Footing User Manual for more explanation on using SkyCiv Foundation.
RESULT COMPARISON
Shear and moment values and graph are compared in the figure below:
Figure 3: (1) Shear and Moment Diagram from skyCiv. (2) Taken in Figure 10.29 in Book 1 reference.
The most significant results are compared in the table below:
| Results | ||
|---|---|---|
| Parameter | Manual | SkyCiv |
| One way shear | ||
| Actual Shear at critical | 437.167* | 438.41 |
| ΦVc | 445* | 440.89 |
Albert Pamonag
Structural Engineer, Product Development
B.S. Civil Engineering
