الفهرس 
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Abstract
Because of continual degradation of concrete structures due to ageing, deterioration-induced environmental conditions, inadequate maintenance, and the need to meet the requirements of updated codes and guidelines, there is an increasing need to strengthen and upgrade existing concrete buildings in both seismic and non-seismic areas. Textile-reinforced mortar (TRM) is an advanced cement-based composite material that was introduced about a decade ago in the field of structural retrofitting. TRM is made up of high-strength fibers in the form of textiles that are embedded in inorganic matrix like cement mortars. TRM has many well-known advantages, including fire resistance, cheap cost, and the ability to be applied to wet surfaces and at low temperatures.
This study involves an experimental and analytical work for using textile reinforced mortar (TRM) to enhance the flexural strength of reinforced concrete (RC) beams and slabs.
Firstly, the tensile properties of the textile were obtained through testing bare textiles, and TRM coupons. The tension test was carried out on nineteen sets of pin action specimens. The variables studied in the current research are textile mesh size, number of plies, and mortar type, as well as coating some of the textiles with epoxy. The results indicated that the ductility and the ultimate load of specimens increased by increasing the number of plies. The polymer modified cementitious mortar reinforced with glass fibers is the most efficient in enhancing the strength and ductility among the different types of mortars used in the study. Moreover, coating textiles with epoxy enhanced the ultimate load by about 25% compared to the uncoated specimens. The experimental results were compared with the corresponding values predicted by a model reported in the literature. The experimental results were in good agreement with those predicted using the model.
Second, it has long been known that the effectiveness of any external strengthening technique in improving the flexural capacity of concrete members is essentially determined by the bond between the strengthening material and the concrete substrate. Therefore, the bond between TRM and concrete was studied through ten pullout bending test. The test variables considered were concrete compressive strength, textile mesh size, surface preparation and development length. The test results showed that the increase in substrate compressive strength from C20 to C30 and C40 increased the bond strength by 36% and 68%, respectively. Also, it was found that the roughening of the concrete changed the failure mode from BTRM debonding to textile rupture except for specimens incorporating M34 mesh size as the failure was in the interface between textile and mortar. Based on the experimental results, an analytical expression was proposed to predict the bond strength and compute the bond strength between concrete and BTRM.
The flexural strength was assessed through testing seven slabs and six beams. The test parameters were number of plies, textile mesh size, mortar type and mechanical anchorage. The test results showed that strengthening of beams using 3 or 5 layers increased the ultimate load capacity by 15% compared to control specimen. Also, it was found that an increase of 177% to 315% in slabs’ flexural strength were achieved using basalt textile reinforced mortar depending on the amount of the textiles.
Finally, a finite element model was developed for slab specimens and verified with the experimental results. After verification, a parametric study was carried out to study more parameters such as steel reinforcing ratio, concrete compressive strength, and number of plies. The verified model showed a good agreement with the experimental results. The parametric study showed that increasing the reinforcing ratio decreased the strength gain.