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Using ACI-19 to Analysis and Design a Spiral RC Staircase

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This study aims to reduce the time and effort required to design an economical spiral staircase according to the latest ACI code. Geometrically, the spiral staircase is a complex 3D structure subjected to three forces and three moments. The values of the six internal stresses generated in each section vary along the staircase and are calculated through a series of long and complex equations. By creating six simplified diagrams of all the variable forces and moments, two locally familiar cases were designed: one with a total angle of 240° and other with an angle of 180°. The created diagrams represent the easiest way to find the locations of the maximum forces and moments. Thus, the structural analysis results will be ready for the design according to approved specifications. After creating algorithms based on ACI-19 requirements, the authors designed both cases and drew the details of the reinforcing bars. In comparison, it is considered more appropriate to construct stairs of 180° in residential and commercial buildings because they meet the architectural requirements and are more economical than those of 240°
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Staircase; Helical Stair; Spiral Stair; Concrete Stair; Reinforced Concrete

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ACI Committee 318 (2019) Building Code Requirements for Reinforced Concrete (ACI 318-19), American Concrete Institute, Detroit, USA.

Z. Wadud, (2002), A Simple Design Approach for Helicoidal Stair Slabs, MSc. thesis, Bangladesh University of Engineering And Technology, Dhaka, Bangladesh.

K. I. Waked, (2000), Design of RC stairs according to Egyptian code 1990, 4th ed., SBH, Cairo, Egypt.

A. M. B. Al-Shamma, (2014), Novel Flowchart for Design of Concrete Rectangular Beams, International Journal of Scientific & Engineering Research, Vol. 5, Iss. 2, pp. 231-233.

A. M. B. Al-Shammaa, (2014), Create Shear Stair for Reinforcement of Concrete Beams, International Journal of Research in Engineering and Technology, Vol. 3, Iss. 1, pp. 412-414.

A. H. Nilson, D. Darwin, and C.W. Dolan, (2010), Design of Concrete Structures, 14th ed., McGraw-Hill, USA.

E. G. Nawy, (2009), Reinforced Concrete a Fundamental Approach, 6th ed., Pearson Education, USA.

C. Wang, C. G. Salmon, and J. A. Pincheira, (2007), Reinforced Concrete Design, 7th ed., Wiley, USA.

M. N. Hassoun, and A. Al-Manaseer, (2008), Structural Concrete Theory and Design, 4th ed., Wiley, USA.

J. C. McCormac, and R.H. Brown, (2009), Design of Reinforced Concrete, 8th ed., Wiley, USA.

G. F. Limbrunner, and A.O. Aghayere, (2007), Reinforced Concrete Design, 6th ed., Pearson Education, USA.

C. Olivieri, C. Cennamo, C. Cusano, (2022), Masonry Spiral Stairs: A Comparison between Analytical and Numerical Approaches, Appl. Sci. 12(9).

A. Dell'Endice, M. J. DeJong, T. V. Mele, P. Block, (2022), Structural analysis of unreinforced masonry spiral staircases using Discrete Element modelling, Structures, Vol. 46, P.P 214-232.

M. Angelillo, C. Olivieri, M. J. DeJong, (2021), A new equilibrium solution for masonry spiral stairs, Engineering Structures, Vol. 238.

J. A. Schultz, J. D. Jesse, (2020),Simplified Stress Design of Helicoidal HSS Beams, Journal of Architectural Engineering, Vol. 26, Iss. 1.

A. Cutolo, F. Guarracino, C. Olivieri, Ida Mascolo, (2022), nonlinear FE analysis of a masonry spiral staircase in nisida: a refined numerical case study, International Journal for Multiscale Computational Engineering, Vol. 20, Iss.5, 2022, pp. 105-114.

M. Rossi, C. Calderini, B. Di Napoli, L. Cascini, F. Portioli, (2020), Structural analysis of masonry vaulted staircases through rigid block limit analysis, Structures, Vol. 23, pp. 180-190.

G. D'Acunto, A. Calandriello, E. Caldo,(2022), Generative Modeling as an Alternative Analysis Tool for Cultural Heritage. The Case Study of Helicoidal Staircases, Architectural Graphics, Conference paper, Vol.1, pp. 97-106.

José Santos, Pedro Andrade, Patrícia Escórcio, (2019), Pre-design of laterally supported stair steps, Engineering Structures, Vol. 182, pp. 51-61.

W. Y. Lin, (2020), Automatic Generation of High-Accuracy Stair Paths for Straight, Spiral, and Winder Stairs Using IFC-Based Models, ISPRS Int. J. Geo-Inf., 9(4).

Abduljabbar, M., Abdulsahib, W., Almuhsin, B., Numerical Study of Concrete Beams With and Without Stirrups Under Impact Loading, (2023) International Review of Civil Engineering (IRECE), 14 (2), pp. 73-81.

T. Türker, B. Demirtaş, Ali Ural, Mehmet A. Kömür,(2022), Seismic Behavior of Historical Inclined Minarets under Near and Far Fault Ground Motions, Journal of Earthquake Engineering, Vol. 26, Iss. 11.

M. N. Hassoun, A. Al-Manaseer, (2020), Structural concrete, theory and design, 7th ed., Joh Wiley, USA.

Al-Bayati, A., Torsion Strength Prediction of Reinforced Concrete Beams, (2023) International Review of Civil Engineering (IRECE), 14 (2), pp. 153-163.

A. M. Al-Shammaa and S. K. Al-Mamoori (2021) A Design Chart for Optimum Dimensions of Reinforced Concrete Cantilever Beams, IOP Conf. Series: Materials Science and Engineering, Vol. 1094, pp. 1-11.

Nuroji, N., Hung, C., Prasetya, B., Han, A., The Behavior of Reinforced Concrete Members with Section Enlargement Using Self-Compacting Concrete, (2020) International Review of Civil Engineering (IRECE), 11 (3), pp. 121-126.

Akmaluddin, A., Murtiadi, S., Anshari, B., Flexural Stiffness of Normal and Sandwich Reinforced Concrete Beam Exposed to Fire Under Fixed Loading, (2020) International Review of Civil Engineering (IRECE), 11 (1), pp. 36-44.

C. Aksoylu, Ş. Yazman, Y. O. Özkılıç , L. Gemi , M. H. Arslan,(2020), Experimental analysis of reinforced concrete shear deficient beams with circular web openings strengthened by CFRP composite, Composite Structures, Vol. 249.

Tougui, T., Darnif, H., Azelmad, E., El Maskaoui, Z., Bousshine, L., Finite Element Analysis of a Semi-Rigid Endplate Beam-to-Column Joint with Stiffeners, (2023) International Review of Civil Engineering (IRECE), 14 (1), pp. 31-41.

A. Dua, A. Braimah, M. Kumar, (2020), Experimental and numerical investigation of rectangular reinforced concrete columns under contact explosion effects, Engineering Structures, Vol. 205.

A.M. Al-Shammaa and S. K. Al-Mamoori (2021) A Design Chart for Optimum Dimensions of Reinforced Concrete Cantilever Beams, IOP Conf. Series: Materials Science and Engineering, Vol. 1094, pp. 1-11.


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