FINITE ELEMENT CHARACTERIZATION OF THE BEHAVIOUR OF MASONRY INFILL SHEAR WALLS WITH AND WITHOUT OPENINGS

• Author / Creator

  Nazief, Mohammed A

• The current design practice is to ignore the interaction between masonry infill walls and containing frames due to the inadequate and incomplete guidance in current codes and standards. Most investigations on the behaviour of masonry infill shear walls were performed on scaled specimens and restricted by budget and time to a limited number of parameters. This research aims to help fill the knowledge gap in the understanding of the lateral load-lateral displacement response of masonry infill walls with and without openings.
  A finite element (FE) technique was developed to model masonry infilled frames using the simplified micro-modelling approach. Behaviour of contact between the different masonry units and between the masonry infill wall and containing frame was idealized by a traction–separation law that accounts for separations due to tension and shear cracks. The commercially available FE package, ABAQUS, was used to build 3D models for 9 steel and 8 RC masonry infilled frames with and without openings from four major experimental programs. The lateral load–displacement response and failure mechanism of the FE models were in strong agreement with the experimental results. The validated FE technique was used to study some of the most influential parameters such as: infill wall aspect ratio, size and location of gaps between the frame and the infill wall, presence and size of frame haunches, and size and location of window and door openings. The FE analysis was carried out using two master full-size masonry infilled steel and RC frame models representing a 3-storey building designed to the 2010 NBCC.
  In addition to the 17 models used to validate the FE technique, 34 solid infilled frames and 50 infilled frames with openings were built and analyzed for the effect of the parameters under investigation. It was found that a full separation gap up to 5 mm between the infill wall and the frame does not significantly impact the behaviour; to ensure a complete separation, a full separation gap of 10 mm or higher is needed. Another finding is that frame haunches could increase the lateral load resistance by more than 50% compared to frames with no haunches. A single diagonal compression strut was formed in infill walls with openings 10% or less of the wall surface area. Sliding shear was the dominating failure mode for infill walls with large opening size and/or low aspect ratios. Openings that are 15–20% of the infill wall surface area resulted in 50% and more reduction in the lateral load resistance. Still, much research is needed to gain better understanding of the true behaviour of this complex lateral load resisting system.

• Subjects / Keywords

  • Non-linear behaviour
  • Steel and RC frames
  • Interface modelling
  • In-plane lateral behaviour
  • Finite-element-analysis
  • Concrete masonry infill wall

• Graduation date

  Fall 2014

• Type of Item

  Thesis

• Degree

  Doctor of Philosophy

• DOI

  https://doi.org/10.7939/R3437S

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.