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Reinforced concrete structures, particularly in cold areas, experience early deterioration due to steel corrosion. Fiber-Reinforced Concrete (FRC) is an emerging construction material and cost-effective substitute for conventional concrete to enhance the durability and resistance against crack development. This article examines the structural performance of hybrid ferro fiber reinforced concrete slabs (mix ratio of mortar 1:2) comprising silica fume, layers of spot-welded mesh and different ratios of polypropylene fibers. The ferrocement slabs are compared with a conventional Reinforced Cement Concrete (RCC) slab (mix ratio of 1:2:4). The experimental work comprised a total of 13 one-way slabs, one control specimen and three groups of ferrocement slabs divided based on different percentages of Poly Propylene Fibers (PPF) corresponding to 0.10%, 0.30% and 0.50% dosage in each group. Furthermore, in each group, the percentage of steel ratio in ferrocement slabs varied between 25% and 100% of the steel area in the reinforced concrete control slab specimen. For evaluating the structural performance, the observation of deflection, stress-strain behavior, cracking load and energy absorption are critical parameters assessed using LVDTs and strain gauges. At the same time, the slabs were tested in flexure mode with third point loading. The experimental results showed that the first cracking load and ultimate deflection for fibrous specimens with 0.5% fiber and 10% silica fume increased by 15.25% and 13.2% compared with the reference RCC control slab. Therefore, by increasing the percentage of PPF and steel wire mesh reinforcement in the ferrocement slab, the post-cracking behavior in terms of deflection properties and energy absorption capacity was substantially enhanced compared to the RCC control slab.

The failure of most reinforced concrete structures is due to inadequate seismic design and detailing, poor construction techniques and/or the use of low-strength concrete (LSC). Retrofitting such structures with fibre-reinforced polymer wrapping rather than traditional concrete or steel jacketing is an emerging popular strengthening technique. In the research reported in this paper, carbon-fibre-reinforced polymer (CFRP) was used for external confinement of LSC bridge pier columns, which resulted in appreciable improvements in flexural strength and load-carrying capacity. Experimental tests and numerical simulations of quarter-size CFRP-wrapped circular columns under quasi-static cyclic loading were performed to evaluate the improvement in lateral load-carrying capacity. The results revealed that the confining action of the CFRP wrapping resulted in significant enhancements in the strength and ductility properties of the columns. It enhanced their energy dissipation capabilities and made them more able to tolerate even larger earthquake forces without an appreciable loss in stiffness.