Research on test and bearing capacity calculation model of two-way RC slabs strengthened with textile reinforced mortar

doi:10.19936/j.cnki.2096-8000.20230228.003

Abstract

Abstract: To study the effect of textile reinforced mortar (TRM) on the flexural capacity of two-way reinforced concrete (RC) slab, three two-way RC slabs under monotonic loading distributed at four points were tested. And the influence of different strengthening techniques on the flexural capacity and bending deformation capacity of the two-way RC slab was studied. It was concluded that the application of TRM to strengthen the two-way RC slab can effectively improve its flexural capacity and bending deformation capacity. Compared with the unreinforced test plates, the flexural capacity and energy absorption of the two strengthened plates are increased by 54.2% and 43.8%, 75.5% and 49.1% respectively. Compared with the unreinforced test plates, the post-cracking stiffness of the test plates are increased by 145.2% and 83.4% with and without interfacial agent, which shows that the application of interface agent for interface treatment can improve the adhesion between the strengthening layer and the old structure, thus preventing the initiation and development of cracks between the new and old interfaces. Based on the theory of plastic hinge lines, a simple calculation formula for the flexural capacity of the two-way RC slab strengthened with TRM was proposed, which provided the reference for the application of TRM for strengthening projects.

Key words: textile reinforced mortar, two-way slab, carbon fiber net, the theory of plastic hinges, fiber strength utilization rate

CLC Number:

TB332

LI Yongzhang, WU Di. Research on test and bearing capacity calculation model of two-way RC slabs strengthened with textile reinforced mortar[J]. COMPOSITES SCIENCE AND ENGINEERING, 2023, 0(2): 24-33.

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