Cyclic loading tests of slender concrete masonry shear walls
DOI:
https://doi.org/10.5459/bnzsee.15.1.3-21Abstract
The design, construction and testing of three slender concrete masonry shear walls is reported. The three walls, modelling 190 mm thick blockwork walls of four to five stories height to a scale of 1:0.737 were subjected to cyclic reversals of in-plane displacements at gradually increasing ductility factors, simulating the effects of seismic loading. Variables between walls included axial load level, and whether or not confining plates were placed in the mortar beds in the compression zones of the potential plastic hinge region. All walls were constructed by conventional methods, and included lapped starter bars within the plastic hinge.
Results indicated that the unconfined walls suffered strength degradation at levels of ductility lower than those required by current ductile design practice. This was particularly the case for the wall with heavy axial> loading, and confirmed theoretical predictions of available ductility based on a limiting ultimate compression strain of 0.25%. Response of the confined wall exhibited greatly improved behaviour compared with an otherwise identical unconfined wall. In all walls behaviour was significantly, and adversely, affected by the lapping of flexural steel at the wall base.
References
Priestley, M.J.N, and Bridgeman, D.O., 'Seismic Resistance of Brick Masonry Walls', Bull. NZNSEE, Vol.7, No. 4, Dec. 1974, pp. 167-187. DOI: https://doi.org/10.5459/bnzsee.7.4.167-187
Priestley, M.J.N., 'Seismic Resistance of Reinforced Concrete Masonry Shear Walls with High Steel Percentages', Bull. NZNSEE, Vol.10, No. 1, March 1977, pp.1-16. DOI: https://doi.org/10.5459/bnzsee.10.1.1-16
Trounce, M.J. and Priestley, M.J.N., 'Seismic Behaviour of Reinforced Concrete Masonry Shear Walls', Department of Civil Engineering, University of Canterbury, Research Report 78-19, Feb. 1978, 112p.
Williams, D., 'Seismic Behaviour of Reinforced Masonry Shear Walls', Ph.D. Thesis, Department of Civil Engineering, University of Canterbury, 1971, 107p.
Mayes, R.L., Omote, Y. and Clough R.W., 'Cyclic Shear Tests of Masonry Piers Volume 1 - Test Result1. University of California, Berkeley, Earthquake Engineering Research Centre Report EERC 76-8, May 1976, 84p.
Hidalgo, P.A., Mayes, R.L., McNiven, H.D., and Clough, R.W., 'Cyclic Loading Tests of Masonry Single Piers' (3 vols.), University of California, Berkeley, Reports EERC 78-27, 78-28 and 29-12.
Priestley, M.J.N., 'Ductility of Unconfined Masonry Shear Walls', Bull. NZNSEE Vol. 14, No. 1, March 1981, pp.12-20. DOI: https://doi.org/10.5459/bnzsee.14.1.12-20
- 'The Design of Concrete Structures1 , DZ3101, Standards Association of New Zealand, 1980.
- "The Design of Reinforced Masonry', DZ4210, Part B, SANZ, Wellington, 1980.
Priestley, M.J.N, and Elder, D.McG., 'Seismic Behaviour of Slender Masonry Shear Walls', Dept. of Civil Eng., University of Canterbury, Research Dept. (to be published).
Priestley, M.J.N.; Ductility of Confined Masonry Shear Walls1 Bull. NZNSEE, Vol.15, No.1, March 1982. DOI: https://doi.org/10.5459/bnzsee.15.1.22-26
Hilsdorf, H.K., 'An Investigation into the Failure Mechanism of Brick Masonry Under Axial Compression', Designing, Engineering and Construction with Masonry Products, F.B. Johnston Ed., Gulf Pub. Co., Houston, Texas, Mag. 1969, pp. 34-41.
