URM CAVITY WALLS: SIMPLE AND EXPERIMENTALLY PROOF-TESTED RETROFIT

Australia earthquake engineering Conference, Newcastle

REFERENCE

Tocher H., Slavin N., Stanišić A., Dizhur D. (2019). URM cavity walls: Simple and experimentally proof-tested retrofit. In the proceedings of the Australian Earthquake Engineering Society Conference, Newcastle, Australia

Scope and methodology

• The test campaign aimed to study simple solutions to substantially increase the out-of-plane performance of cavity brick walls

• 2 single-single cavity-walls and 2 double-single cavity-walls were tested in as-built and strengthened configuration using air-bags to subject the walls to semi-cyclic load

• The retrofit solution consisted of different arrangements of remedial cavity-ties

• Adopted remedial cavity-ties were able to transfer shear and improve composite action between the leaves

FINDINGS

• The optimal spacing for shear transferring ties in cavity walls used was approximately 460 mm horizontal x 400 mm vertical.

• This tie spacing corresponds to the state ‘well-tied’, which was defined as sufficient to ensure that the failure mode was not related to tie performance.

• The tested performance of well-tied cavity walls aligned with the theoretical predictions. Thus, well-tied cavity walls can be assessed for out-of-plane capacity as if they were solid walls of the same total thickness (composite behaviour achieved).

• Spacing of ties to result in a well-tied condition do not depend upon the predicted lateral load but instead upon the geometry of a wall.