Seismic response of RC walls coupled by slabs without coupling beams

Janevski, Antonio (author), Isaković, Tatjana (author)

The article investigates the seismic response of reinforced concrete (RC) walls coupled by slabs without coupling beams. The primary objective of the study was to determine the significance of wall piers coupling provided by the slabs and the role of their interaction in the overall seismic behaviour of the system. The influence of various parameters on the coupling level (CL) was systematically evaluated. Comprehensive non-linear response history and static analyses demonstrated that a significant CL can be achieved by slabs alone—up to 50 %. The criterion identifying buildings where large CL can be expected was defined and quantified for the first time. Slender walls with an aspect ratio exceeding 4 can be subjected to large CL, when a significant effective slab width can be activated (often up to the full span width). In such cases, the response was found to differ significantly from that typically observed in cantilever walls. A significant CL caused the seismic action to considerably alter the axial forces. The ratio of axial forces induced by seismic action to those due to gravity loads was found to be as high as 80 %. These changes further influenced the strength and stiffness of the piers, leading to significant redistributions of shear demand between piers, which cannot be captured by elastic analysis methods. For large CLs, the shear demand on individual wall piers subjected to axial compression forces induced by the seismic action reached up to 70 % of the total shear demand. It was demonstrated that, in the non-linear range, shear demand can also increase due to higher modes of vibration. While the amplification of shear forces due to coupling (frame action) increased with increasing CL, shear force amplification due to higher modes was found to decrease. Since simplified non-linear pushover analysis cannot capture this amplification, the values of shear forces should be corrected. For the first time, simple correction factors based on non-linear response history analyses were proposed for this purpose. In the case of the comprehensive set of analysed buildings, the accuracy of these corrections was within 20 %. The findings of this study highlight the importance of using non-linear analysis for the accurate seismic design of walls coupled only by slabs, emphasising the complex nature of the interaction between wall piers and slabs during seismic events.

• Language: English
• Keywords: civil engineering, earthquake engineering, engineering structures, RC walls, seismic response, coupling level, frame action, higher mode effects, shear amplification, non-linear analysis
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FGG - Faculty of Civil and Geodetic Engineering
• Publication status: Published
• Publication version: Version of Record
• Year: 2025
• Number of pages: 16 str.
• Numbering: Vol. 329, art. 119861
• PID: 20.500.12556/RUL-167346
• UDC: 624.07
• ISSN on article: 0141-0296
• DOI: 10.1016/j.engstruct.2025.119861
• COBISS.SI-ID: 226058243
• Publication date in RUL: 17.02.2025

Record is a part of a journal

• Title: Engineering structures
• Shortened title: Eng. struct.
• Publisher: Elsevier
• ISSN: 0141-0296
• COBISS.SI-ID: 7750666

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.

Secondary language

• Language: Slovenian
• Keywords: gradbeništvo, potresno inženirstvo, gradbene konstrukcije

Projects

• Funder: ARIS - Slovenian Research and Innovation Agency