Sprayed Glass Fiber-Reinforced Mortar with or without Basalt Textile Reinforcement for Jacketing of Low-Strength Concrete Prisms

The external jacketing method using cement-based matrices and textile reinforcement has gained popularity for the enhancement of strength and ductility characteristics of reinforced concrete members. In this study, glass fiber-reinforced mortar (GFRM) with or without basalt textile reinforcement was used for external jacketing of low-strength concrete prisms. An innovative spraying method was used during the application of the cement-based matrix to the specimen's surface. Investigations were carried out on a large number of concrete prisms with five different cross-sectional geometries (circular, square, and rectangular, with cross-sectional aspect ratios of 1.5, 2, and 3). At the end of the tests, it was shown that the proposed retrofit methodology is effective for the enhancement of performance of low-strength concrete members. The spraying technique is practical and feasible, particularly for the cases in which access to the structural members that are destined to be retrofitted is limited. Furthermore, a simple analytical approach based on the effectively confined concrete area concept is also presented for predicting the peak strength and the ultimate strains of the retrofitted specimens. (C) 2019 American Society of Civil Engineers.