Polymer concrete (PC) has been favoured over Portland cement concrete when low permeability, high adhesion, and/or high durability against aggressive environments are required. In this research, a new class of PC incorporating Multi-Walled Carbon Nanotubes (MWCNTs) is introduced. Four PC mixes with different MWCNTs contents were examined. MWCNTs were carefully dispersed in epoxy resin and then mixed with the hardener and aggregate to produce PC. The impact strength of the new PC was investigated by performing low-velocity impact tests. Other mechanical properties of the new PC including compressive, flexural, and shear strengths were also characterized. Moreover, microstructural characterization using scanning electron microscope and Fourier transform infrared spectroscopy of PC incorporating MWCNTs was performed. Impact test results showed that energy absorption of PC with 1.0 wt% MWCNTs by weight of epoxy resin was significantly improved by 36 % compared with conventional PC. Microstructural analysis demonstrated evidence that MWCNTs significantly altered the chemical structure of epoxy matrix. The changes in the microstructure lead to improvements in the impact resistance of PC, which would benefit the design of various PC structural elements.

This research article investigated the notch sensitivity of two different glass fibre architectures, namely short and 2D plain-woven glass fibres reinforced with unsaturated polyester and epoxy matrix composites fabricated by the hand lay-up technique. This was carried out through open hole tension tests at different ratios of the specimen hole diameter to the specimen with three different values (0.1, 0.2, 0.5) compared to the unnotched specimen. The notch sensitivity of these composites was evaluated using the residual tensile strength by the application of Whitney–Nuismer Mathematical Model. The results showed that by using polyester matrix, the notch sensitivity of composites reinforced with plain-woven glass fibre is higher than that of short glass fibre at different D/W ratios. On the other hand, on testing epoxy matrixes, the notch sensitivity of composites reinforced with plain-woven glass fibre is lower than that of short glass fibre at different D/W ratios.

This research article investigated the notch sensitivity of two different glass fibre architectures, namely short and 2D plain-woven glass fibres reinforced with unsaturated polyester and epoxy matrix composites fabricated by the hand lay-up technique. This was carried out through open hole tension tests at different ratios of the specimen hole diameter to the specimen with three different values (0.1, 0.2, 0.5) compared to the unnotched specimen. The notch sensitivity of these composites was evaluated using the residual tensile strength by the application of Whitney–Nuismer Mathematical Model. The results showed that by using polyester matrix, the notch sensitivity of composites reinforced with plain-woven glass fibre is higher than that of short glass fibre at different D/W ratios. On the other hand, on testing epoxy matrixes, the notch sensitivity of composites reinforced with plain-woven glass fibre is lower than that of short glass fibre at different D/W ratios.

This research article investigated the notch sensitivity of two different glass fibre architectures, namely short and 2D plain-woven glass fibres reinforced with unsaturated polyester and epoxy matrix composites fabricated by the hand lay-up technique. This was carried out through open hole tension tests at different ratios of the specimen hole diameter to the specimen with three different values (0.1, 0.2, 0.5) compared to the unnotched specimen. The notch sensitivity of these composites was evaluated using the residual tensile strength by the application of Whitney–Nuismer Mathematical Model. The results showed that by using polyester matrix, the notch sensitivity of composites reinforced with plain-woven glass fibre is higher than that of short glass fibre at different D/W ratios. On the other hand, on testing epoxy matrixes, the notch sensitivity of composites reinforced with plain-woven glass fibre is lower than that of short glass fibre at different D/W ratios.

This research article investigated the notch sensitivity of two different glass fibre architectures, namely short and 2D plain-woven glass fibres reinforced with unsaturated polyester and epoxy matrix composites fabricated by the hand lay-up technique. This was carried out through open hole tension tests at different ratios of the specimen hole diameter to the specimen with three different values (0.1, 0.2, 0.5) compared to the unnotched specimen. The notch sensitivity of these composites was evaluated using the residual tensile strength by the application of Whitney–Nuismer Mathematical Model. The results showed that by using polyester matrix, the notch sensitivity of composites reinforced with plain-woven glass fibre is higher than that of short glass fibre at different D/W ratios. On the other hand, on testing epoxy matrixes, the notch sensitivity of composites reinforced with plain-woven glass fibre is lower than that of short glass fibre at different D/W ratios.

This research compares the notch sensitivity of two different glass fibre including short and plain-woven glass fibres reinforced with unsaturated polyester and epoxy matrix composites fabricated by the hand lay-up technique. This was carried out through open hole tension tests at different ratios of the specimen hole diameter to the specimen width with three different values (0.1, 0.2, 0.5) compared to the unnotched specimen. The notch sensitivity of these composites was evaluated using the residual tensile strength by the application of Whitney-Nuismer mathematical model. The results indicated that the characteristic distance of woven glass fiber polyester composites is lower than that of short glass fiber polyester composites composites for different D/W ratios. Therefore, the notch sensitivity of woven glass fiber polyester composites is higher than that of short glass fiber polyester composites. On the other hand, In epoxy-matrix composites, the characteristic distance of woven glass fiber epoxy composites is higher than that of short glass fiber epoxy composites for different D/W ratios. Therefore, the notch sensitivity of woven GF epoxy composites is less sensitive than short GF epoxy composites.

This research compares the notch sensitivity of two different glass fibre including short and plain-woven glass fibres reinforced with unsaturated polyester and epoxy matrix composites fabricated by the hand lay-up technique. This was carried out through open hole tension tests at different ratios of the specimen hole diameter to the specimen width with three different values (0.1, 0.2, 0.5) compared to the unnotched specimen. The notch sensitivity of these composites was evaluated using the residual tensile strength by the application of Whitney-Nuismer mathematical model. The results indicated that the characteristic distance of woven glass fiber polyester composites is lower than that of short glass fiber polyester composites composites for different D/W ratios. Therefore, the notch sensitivity of woven glass fiber polyester composites is higher than that of short glass fiber polyester composites. On the other hand, In epoxy-matrix composites, the characteristic distance of woven glass fiber epoxy composites is higher than that of short glass fiber epoxy composites for different D/W ratios. Therefore, the notch sensitivity of woven GF epoxy composites is less sensitive than short GF epoxy composites.

This research compares the notch sensitivity of two different glass fibre including short and plain-woven glass fibres reinforced with unsaturated polyester and epoxy matrix composites fabricated by the hand lay-up technique. This was carried out through open hole tension tests at different ratios of the specimen hole diameter to the specimen width with three different values (0.1, 0.2, 0.5) compared to the unnotched specimen. The notch sensitivity of these composites was evaluated using the residual tensile strength by the application of Whitney-Nuismer mathematical model. The results indicated that the characteristic distance of woven glass fiber polyester composites is lower than that of short glass fiber polyester composites composites for different D/W ratios. Therefore, the notch sensitivity of woven glass fiber polyester composites is higher than that of short glass fiber polyester composites. On the other hand, In epoxy-matrix composites, the characteristic distance of woven glass fiber epoxy composites is higher than that of short glass fiber epoxy composites for different D/W ratios. Therefore, the notch sensitivity of woven GF epoxy composites is less sensitive than short GF epoxy composites.

This research compares the notch sensitivity of two different glass fibre including short and plain-woven glass fibres reinforced with unsaturated polyester and epoxy matrix composites fabricated by the hand lay-up technique. This was carried out through open hole tension tests at different ratios of the specimen hole diameter to the specimen width with three different values (0.1, 0.2, 0.5) compared to the unnotched specimen. The notch sensitivity of these composites was evaluated using the residual tensile strength by the application of Whitney-Nuismer mathematical model. The results indicated that the characteristic distance of woven glass fiber polyester composites is lower than that of short glass fiber polyester composites composites for different D/W ratios. Therefore, the notch sensitivity of woven glass fiber polyester composites is higher than that of short glass fiber polyester composites. On the other hand, In epoxy-matrix composites, the characteristic distance of woven glass fiber epoxy composites is higher than that of short glass fiber epoxy composites for different D/W ratios. Therefore, the notch sensitivity of woven GF epoxy composites is less sensitive than short GF epoxy composites.

This study presents the shear behavior of reinforced concrete (RC) T-beams with innovative steel stirrups hybridized in the longitudinal direction with a fiber-reinforced polymer (FRP) composite. Six beams were experimentally tested: three beams were reinforced with the hybrid steel-FRP stirrups, and the others served as control samples and were reinforced with conventional steel stirrups. Furthermore, a two-dimensional finite-element (FE) model was created and executed using FE analysis software to examine the effect of several influential parameters, including the type and amount of FRP used in producing the hybrid stirrups. Large-scale beams reinforced with carbon FRP (CFRP) stirrups were numerically simulated before and after replacing the transverse CFRP reinforcement with steel-FRP stirrups. Compared with conventional RC beams, concrete beams reinforced with steel-FRP stirrups successfully showed a considerable increase in the beam shear strength and deformability. Moreover, hybrid steel-FRP stirrups can provide design engineers with a new, flexible design to control both the structural response and the construction cost.