Abstract
The point-load test method (PLTM) commonly used in the geotechnical area is shown in this paper to estimate the compressive strength of in situ masonry mortar. A specially developed portable PLTM instrument was used for mortar sheet testing. The mortar sheets were removed from horizontal masonry joints by drilling cores out, with little preparatory work required. The test mortar sheets were subjected to pressure from two opposing cone heads, and the peak load at the failure of the mortar sheet was recorded. The effect of specimen size and mortar thickness on the point-load strength was examined. A suitable size of mortar sheet was selected for the experiment. The thickness correction method was used to improve the accuracy of the empirical formula. Scattering characteristics were investigated to check the reliability and repeatability of the PLTM results. A strong relationship was noted between the point-load strength of the mortar sheet and cube compressive strength, ranging from M2.5 to M15.0. Contrast tests with other available test methods verified that the PLTM offers an alternative to the masonry mortar compressive test and has high accuracy, requires little preparation, and involves reproducible and quick operation following specimen extraction from joints.
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Data Availability Statements
All data, models, and codes generated or used during the study appear in the published article.
Acknowledgments
The authors would like to acknowledge the National Natural Science Foundation of China (Grant No. 51908341), the Research Project of Changzhou Institute of Technology (Grant Nos. E3-6701-18-064 and YN18044), which collectively funded this project.
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Published In
Journal of Materials in Civil Engineering
Volume 32 • Issue 10 • October 2020
Copyright
© 2020 American Society of Civil Engineers.
History
Received: Sep 27, 2019
Accepted: Mar 2, 2020
Published online: Jul 27, 2020
Published in print: Oct 1, 2020
Discussion open until: Dec 27, 2020
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