• P-ISSN 0974-6846 E-ISSN 0974-5645

Indian Journal of Science and Technology


Indian Journal of Science and Technology

Year: 2023, Volume: 16, Issue: 4, Pages: 299-308

Original Article

Investigation of Impact of Span Length and Variable Live Loading Conditions on Flat Slab Material Costs

Received Date:28 October 2022, Accepted Date:05 January 2023, Published Date:03 February 2023


Objectives: This study investigates the optimization of reinforced concrete flat slabs and establishes a relationship between span, live load, and material costs. Methods: The study used the direct design method per Saudi Building Code limitations, iterative design, and pattern search methods to establish a mathematical model that prescribes the span-cost relationship. The study conducted variable live loading tastings and cost estimates on multiple flat slab panels with distinct dimensions. Findings: The results showed that slab material unit cost increases significantly with span while live load had little impact. Material costs included concrete, steel, and forms which compose 36%, 52%, and 12%, respectively of the total. Each increment in span by 1 meter raises slab material unit cost by 19% starting form 4 meters span as a baseline. Increasing live load by 1 kN/m2 increase cost by roughly 2% for square panels and 1% for rectangular ones. However, results proved that using 1:1 panel dimension is more economical than panels with 2:1 ratio. Novelty: The study provided a mathematical model to estimate flat slab cost more accurately in preliminary estimations before the design phase.
Keywords: Material Costs; Flat Slab Cost; Live Load Impact on Cost; Span Impact on Cost; Slab Unit Cost; Cost Optimization


  1. Jayasinghe A, Orr J, Ibell T, Boshoff WP. Minimising embodied carbon in reinforced concrete flat slabs through parametric design. Journal of Building Engineering. 2022;50:104136. Available from: https://doi.org/10.1016/j.jobe.2022.104136
  2. Aidy A, Rady M, Mashhour IM, Mahfouz SY. Structural Design Optimization of Flat Slab Hospital Buildings Using Genetic Algorithms. Buildings. 2022;12(12):2195. Available from: https://doi.org/10.3390/buildings12122195
  3. Abohashish A, Ebid AM. Estimating The Economic Quantities of Different Concrete Slab Types. International Journal of Innovative Research in Science, Engineering and Technology. 2015;4(5). Available from: https://doi.org/10.15680/IJIRSET.2015.0405002
  4. Ahmad O. Financial comparative study between post-tensioned and reinforced concrete flat slab. International Journal of Advanced Engineering, Sciences and Applications. 2022;3(1):1–6. Available from: https://doi.org/10.47346/ijaesa.v2i2.67
  5. Olmati P, Sagaseta J, Cormie D, Jones AEK. Simplified reliability analysis of punching in reinforced concrete flat slab buildings under accidental actions. Engineering Structures. 2017;130:83–98. Available from: https://doi.org/10.1016/j.engstruct.2016.09.061
  6. Alamri H, Nahhas T, Elgohary H. Evaluation of Design Provisions for One-Way Solid Slabs in SBC-304. International Research Journal of Engineering and Technology. 2009;9(2):298–304. Available from: https://www.irjet.net/archives/V9/i4/IRJET-V9I457.pdf
  7. Weng YHH, Qian K, Fu F, Fang Q. Numerical investigation on load redistribution capacity of flat slab substructures to resist progressive collapse. Journal of Building Engineering. 2020;29:101109. Available from: https://doi.org/10.1016/j.jobe.2019.101109
  8. Stochino F, Gayarre FL. Reinforced Concrete Slab Optimization with Simulated Annealing. Applied Sciences. 2019;9(15):3161. Available from: https://doi.org/10.3390/app9153161
  9. Olawale SOA, Tijani MA, Kareem MA, Ogungbire AM, Alabi O. Cost optimisation of the design of reinforced concrete flat slab to BS8110. IOP Conference Series: Materials Science and Engineering. 2019;640(1):012052. Available from: https://doi.org/10.1088/1757-899X/640/1/012052
  10. Samarakoon SMSMK, Hodne B. Parametric Study of Different Unbonded Tendon Layouts in Pre-stressed Concrete Flat Plates. International Journal of Concrete Structures and Materials. 2020;14(1):56. Available from: https://doi.org/10.1186/s40069-020-00433-w
  11. Aidarov S, Nadaždi A, Pugach E, Tošić N, Fuente ADL. Cost-oriented analysis of fibre reinforced concrete column-supported flat slabs construction. Journal of Building Engineering. 2022;51:104205. Available from: https://doi.org/10.1016/j.jobe.2022.104205
  12. Barreto M, Timm M, Passuello J, Molin AD, Masuero D, JR. Life cycle costs and impacts of massive slabs with varying concrete cover. 2021. Available from: https://doi.org/10.1016/j.clet.2021.100256
  13. Ženíšek M, Pešta J, Tipka M, Kočí V, Hájek P. Optimization of RC Structures in Terms of Cost and Environmental Impact-Case Study. 2020. Available from: https://doi.org/10.3390/su12208532
  14. Tartaglia R, Milone A, D'aniello M, Landolfo R. Retrofit of non-code conforming moment resisting beam-to-column joints: A case study. Journal of Constructional Steel Research. 2022;189:107095. Available from: https://doi.org/10.1016/j.jcsr.2021.107095
  15. Silva LSD, Silva LC, Tankova T, Craveiro HD, Simões R, Costa R, et al. Performance of modular hybrid cold-formed/tubular structural system. Structures. 2021;30:1006–1019. Available from: https://doi.org/10.1016/j.istruc.2021.01.066
  16. Dolan ED, Lewis RM, Torczon V. On the Local Convergence of Pattern Search. SIAM Journal on Optimization. 2003;14(2):567–583. Available from: https://doi.org/10.1137/S1052623400374495
  17. Rady M, Mahfouz SY, Taher SEDF. Optimal Design of Reinforced Concrete Materials in Construction. Materials. 2022;15(7):2625. Available from: https://doi.org/10.3390/ma15072625


© 2023 Jari & Abdulghafour. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Published By Indian Society for Education and Environment (iSee)


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