APPLICATION OF STRUT-AND-TIE MODELS IN THE ANALYSIS OF RC WALLS

Geotehnički aspekti građevinarstva i zemljotresno inženjerstvo 2025, Vrnjačka Banja, 15 – 17. oktobar 2025. (pp. 445-456) 

 

АУТОР(И) / AUTHOR(S): Folić Boris Folić Radomir Miloš Čokić

 

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DOI: 10.46793/GEOAG25.445F

САЖЕТАК / ABSTRACT:

This paper presents the application of Strut-and-Tie Models (STM) for the analysis of reinforced concrete (RC) walls. STM, as a system of compressed and tensioned struts and nodes where the struts intersect, enables the tracking of force flow and principal stresses in structural elements. The difference in modeling walls without and with openings is shown. Depending on their orientation, the struts can be vertical, horizontal, or inclined. In the case of bottle-shaped struts, the stress flow from the node through the element is monitored, and in this context, the substitute system of deltoid struts has proven to be very effective. The diagonals can be designed either as simple struts or as a system of five struts, where four struts form the sides of the deltoid and the fifth is the transverse diagonal. The orientation and position of the deltoid can be easily assumed in elements whose sides are approximately equal. However, in the lowest story, the presence of supports affects their shortening. The basis of STM application is the flow of principal stresses, and software packages can be used to verify the adopted strut system. Concentrated loads are introduced into structural elements through nodes. For different load cases, different substitute strut systems are used, and their flow is verified using software packages (Tower, SAP, etc).

КЉУЧНЕ РЕЧИ / KEYWORDS:

STM, RS walls, masonry infill, deltoid diagonal struts, EC2, flow of principal stresses

ПРОЈЕКАТ / ACKNOWLEDGEMENT:   

This paper is supported by Ministry of Science, Technology Development and Innovation of Republic of Serbia. Contract no. 451-03-136/20225-03/200213.

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