Authors:
T. El Bahlouli,O. Hniad,DOI NO:
https://doi.org/10.26782/jmcms.2025.11.00001Keywords:
Central Core Bracing,Dynamic Behavior,Material Optimization,Natural Frequency,Seismic Response,Tower,Tall-Building,Thickness Variation,Abstract
This study introduces a parametric preliminary design of central core bracing tailored for towers and tall buildings dominated by dynamic flexural vibrations and handled by accidental and serviceability deflections. In such slender systems, the determination of the core thickness is of critical importance to structural engineers, as it formally validates the pre-project stage and, subsequently, enables proper structural detailing outcomes in accordance with seismic regulations and technical standards. This issue is a real challenge, as it typically entails an unlimited number of attempted iterations and enormous computational time to converge towards the optimal values of the structural load-bearing elements. To address this problem, we introduce a streamlined methodological approach, structured as a practical guideline, aimed at defining an optimal variation of the thickness profile and facilitating accurate structural sizing. This dynamic and structural optimization is governed by the max-min formulation of the natural frequency eigenvalue. For this, two strategic zones, depending on the height of the tower, were delineated. Additionally, the construction material usage quantity constraint is imposed to ensure its optimal consumption, thereby establishing a bridge between structural design maturity and the ambitions for increasing profits and resource savings. The principal advantage of this mechanical and mathematical resolution lies in its simplicity and practicality, allowing rapid and efficient hand-use calculations. The present paper is crowned by an illustrative case study designed to evaluate the tangible benefits achieved through the dynamic modal analysis.Refference:
I. Abdi F.,: ‘Understanding the impact of high-rise buildings on environmental quality and sustainable urban development’. Journal of Art and Architecture Studies. Vol. 8(2), pp. 13-18, 2019. 10.51148/jaas.2019.3
II. Al Agha W., Almorad W. A., Umamaheswari N., Alhelwani A.,: ‘Study the seismic response of reinforced concrete high-rise building with dual framed-shear wall system considering the effect of soil structure interaction’. Materials today proceedings. Vol. 43(2), pp. 2182-2188, 2021. 10.1016/j.matpr.2020.12.111.
III. Alavi A., Rahgozar P., Rahgozar R.,: ‘Minimum‐Weight Design of High‐Rise Structures Subjected to Flexural Vibration at a Desired Natural Frequency’. Structural Design of Tall and Special Buildings. Vol. 27(15), pp. 1-13, 2018. 10.1002/tal.1515.
IV. Bao L., Yicong F., Graeme J. K.,: ‘Topology optimization using an eigenvector aggregate’. Structural and Multidisciplinary Optimization. Vol. 66(221), pp. 1–19, 2023. 10.1007/s00158-023-03674-x.
V. Davari S. M., Malekinejad M., Rahgozar R.,: ‘An approximate approach for the natural frequencies of tall buildings with trussed‑tube system’. Innovative Infrastructure Solutions. Vol. 6(46), pp. 1-9, 2021. 10.1007/s41062-020-00418-4.
VI. Davidovici V., : ‘La construction en zone sismique’. Le Moniteur. 1999.
VII. Dym Clive L. P. E., Williams Harry E.,: ‘Estimating Fundamental Frequencies of Tall Buildings’. Journal of Structural Engineering. Vol. 133(10), pp. 1-5, 2007.
VIII. Haopeng L., Zhibin X., Yinyuan W., Guan Q., Fengling J., Boqing G., Hongjia L.,: ‘Size optimization design of members for shear wall high-rise buildings’. Journal of Building Engineering. Vol. 61 (105292), pp. 27–37, 2022. 10.1016/j.jobe.2022.105292.
IX. Keihani R., Bahadori-Jahromi A., Goodchild C., Cashell K. A.,: ‘The influence of different factors on buildings’. Structural Engineering and Mechanics. Vol. 76(1), pp. 83-99, 2020. 10.12989/sem.2020.76.1.083.
X. Lam T. Q. K., Ho C. C.,: ‘Shear wall thickness affects high-rise building internal force and horizontal displacement according to TCVN 2737:2023’. Journal of Materials & Construction. Vol. 14 (2), pp. 27–37, 2024. 10.54772/jomc.v14i02.798.
XI. M-Tower Project website, mtower.ma/
XII. Nieto F., Montoya M.C., Hernandez S.,: ‘Shape Optimization of Tall Buildings Cross-Section : Balancing Profit and Aeroelastic Performance’. The Structural Design of Tall and Special Buildings. Vol. 31(18), pp. 1-21, 2022. 10.1002/tal.1982.
XIII. Nitti G., Lacidogna G., Carpinteri A.,: ‘An analytical formulation to evaluate natural frequencies and mode shapes of high-rise buildings’. Curved and Layered Structures. Vol. 8, pp. 307-318, 2021. 10.1515/cls-2021-0025.
XIV. Patel T., Singh P., Dhaakad D., Vaghela S., Chauhan R., Maseleno A., Isnanto R. R.,: ‘Optimization techniques in real estate investment portfolios: A quantitative approach’. Greenation International Journal of Engineering Science. Vol. 1(4), pp. 183-194, 2024. 10.38035/gijes.v1i4
XV. Patil R., Deshpande A.S., Sambanni S.,: ‘Optimal location of shear wall in high rise building subjected to seismic loading’. International Journal For Technological Research In Engineering. Vol. 3(10), pp. 2347-4718, 2016.
XVI. Paz M., Leigh W.,: Structural Dynamics : ‘Theory and Computation ; Updated with SAP 2000’. 5th Edition, Kluwer Academic Publishers, USA, 2004.
XVII. Rahzogar P.,: ‘Free Vibration of Tall Buildings using Energy Method and Hamilton’s Principle’. Civil Engineering Journal. Vol. 6(5), pp. 945–953, 2020. 10.28991/cej-2020-03091519.
XVIII. Rahgozar R., Safari H., Kaviani P.,: ‘Free vibration of tall buildings using Timoshenko beams with variable cross-section’. WIT Transactions on the Built Environment, Structures Under Shock and Impact VIII. Vol. 73(15), pp. 233-242, 2004. 10.2495/SU040231.
XIX. Robot Structural Analysis Professionnal (RSA 2025) website, www.autodesk.com/products/robot-structural-analysis/overview
XX. Rossmann J. S., Dym Clive L. P. E., Bassman L.,: ‘Introduction to Engineering Mechanics : A Continuum Approach’. CRC Press, 2nd Edition, Boca Raton, USA, 2015.
XXI. Tao L., Bin L., Shuting W., Liang G.,: ‘Eigenvalue topology optimization of structures using a parameterized level set method’. Structural and Multidisciplinary Optimization. Vol. 50, pp. 573–591, 2014. 10.1007/s00158-014-1069-z.
XXII. Yaghoobi N., Hassani B.,: ‘Topological optimization of vibrating continuum structures for optimal natural eigenfrequency’. International journal of optimization in civil engineering. Vol. 7(1), pp. 1-12, 2017.

