Title:
Further Thoughts on "Tilt-Up Design Pitfalls"
Author(s):
Peter H. Bischoff
Publication:
Concrete International
Volume:
46
Issue:
10
Appears on pages(s):
39-43
Keywords:
wall, load, moment, deflection
DOI:
10.14359/51743262
Date:
10/1/2024
Abstract:
The article discusses slender wall design at service loads with the new expression for the effective moment of inertia introduced into ACI 318-19(22), which now uses a reduced cracking moment for computing deflection. A recommendation is also made to provide a limiting condition for the axial wall load to avoid erroneous calculation of the factored moment by direct calculation.
Related References:
1. Nagele, T.; Lawson, J.; and Griffin, J., “Tilt-Up Design Pitfalls,” Concrete International, V. 46, No. 2, Feb. 2024, pp. 55-59.
2. ACI Committee 551, “Pitfalls of Deviating from ACI 318 Slender Wall Provisions—TechNote (ACI PRC-551.3-21),” American Concrete Institute, Farmington Hills, MI, 2021, 12 pp.
3. ACI Committee 318, “Building Code Requirements for Structural Concrete and Commentary (ACI 318-19) (Reapproved 2022),” American Concrete Institute, Farmington Hills, MI, 2019, 624 pp.
4. Bischoff, P.H., “Reevaluation of Deflection Prediction for Concrete Beams Reinforced with Steel and Fiber Reinforced Polymer Bars,” Journal of Structural Engineering, V. 131, No. 5, May 2005, pp. 752-767.
5. Bischoff, P.H., “Service Load Deflection of Tilt-Up Concrete Wall Panels,” Canadian Journal of Civil Engineering, V. 45, No. 8, Aug. 2018, pp. 684-689.
6. ACI Committee 318, “Building Code Requirements for Structural Concrete (ACI 318-14) and Commentary (ACI 318R-14),” American Concrete Institute, Farmington Hills, MI, 2014, 519 pp.
7. Scanlon, A., and Bischoff, P.H., “Shrinkage Restraint and Loading History Effects on Deflections of Flexural Members,” ACI Structural Journal, V. 105, No. 4, July-Aug. 2008, pp. 498-506.
8. Scanlon, A., and Murray, D.W., “Practical Calculation of Two-Way Slab Deflections,” Concrete International, V. 4, No. 11, Nov. 1982, pp. 43-50.
9. CSA A23.3-94, “Design of Concrete Structures,” CSA Group, Toronto, ON, Canada, 1994, 199 pp.
10. CSA A23.3-14, “Design of Concrete Structures,” CSA Group, Toronto, ON, Canada, 2014, 291 pp.
11. ACI-SEAOSC Task Committee on Slender Walls, “Test Report on Slender Walls,” J.W. Athey, ed., ACI Southern California Chapter and Structural Engineers Association of Southern California (SEAOSC), Los Angeles, CA, 1982, 134 pp.
12. Ekwueme, C.; Lawson, J.; Pourzanjani, M.; Lai, J.S.; and Lyons, B., “UBC 97 and ACI 318-02 Code Comparison – Summary Report,” SEAOSC Slender Wall Task Group, Jan. 2006, 47 pp.
13. 1997 Uniform Building Code, Volume 2: “Structural Engineering Design Provisions,” International Conference of Building Officials, Whittier, CA, 1997, 492 pp.
14. ACI Committee 318, “Building Code Requirements for Structural Concrete (ACI 318-99) and Commentary (ACI 318R-99),” American Concrete Institute, Farmington Hills, MI, 1999, 391 pp.
15. ACI Committee 318, “Building Code Requirements for Structural Concrete (ACI 318-08) and Commentary,” American Concrete Institute, Farmington Hills, MI, 2008, 465 pp.
16. ACI Committee 551, “Design Guide for Tilt-Up Concrete Panels (ACI 551.2R-15),” American Concrete Institute, Farmington Hills, MI, 2015, 72 pp.