Carbon-fiber-reinforced polymer (CFRP) laminates have gained attention for their potential to reduce carbon emissions in construction. The impact of carbon-fiber-reinforced polymer (CFRP Laminate) on carbon emissions and the influence of elasto-plastic analysis on this technique were studied in this research. This study focuses on how CFRP can affect the environmental footprint of reinforced concrete structures and how elasto-plastic analysis contributes to optimizing this strengthening method. Four flat RC slabs were created to evaluate this technique in strengthening. One slab was used as a reference without strengthening, while the other three were externally strengthened with CFRP. The slabs, which were identical in terms of their overall (length, width, and thickness) as well as their flexural steel reinforcement, were subjected to concentrated patch load until they failed. The strength of two-way RC slabs was analyzed using a concrete plastic damage constitutive model (CDP). Additionally, CFRP strips were applied to the tension surface of existing RC slabs to improve their strength. The load–deflection curves obtained from the simulations closely match the experimental data, demonstrating the validity and accuracy of the model. Strengthening concrete slabs with CFRP sheets reduced central deflection by 17.68% and crack width by 40%, while increasing the cracking load by 97.73% and the ultimate load capacity by 134.02%. However, it also led to a 15.47% increase in CO2 emissions. Also, the numerical results show that increasing the strengthening ratio significantly impacts shear strength and damage percentage.

The objective of this work is to improve the punching strength and control the plastic deformation of two-way reinforced concrete (RC) slabs using carbon fiber reinforced polymer (CFRP) bars. The efficacy of this reinforcement technique was evaluated by constructing four reinforced concrete flat slabs. One specimen was utilized as a reference slab, while the other three specimens were reinforced using the Near Surface Mounted (NSM) CFRP bars approach. The slabs, which had identical dimensions and steel reinforcement, were exposed to patch load, and tested until they reached the point of failure. For evaluating the strength of two-way reinforced concrete (RC) slabs, the Concrete Plastic Damage (CDP) constitutive model was developed and implemented. CFRP bars are inserted into the slab at a depth from the tension face to enhance their strength. The investigation commences with the calibration of a numerical model utilizing data obtained from laboratory experiments. This will be achieved by establishing an advanced analytical method that incorporates the plasticity of concrete damage and the use of CFRP bars, along with a multiplier to determine the plastic limit load. Numerical simulations are employed to investigate shear dynamics by including diverse elements. The results showed that an increase in the ratio of strengthening had a significant effect on shear strength.

This study explores a technique for enhancing the punching strength of reinforced concrete (RC) flat slabs, namely carbon fiber reinforced polymer (CFRP). Four large-scale RC flat slabs were fabricated, to assess the efficacy of this strengthening method. One slab served as a reference and the three other specimens were strengthened with CFRP, as a method of external strengthening. These slabs, featuring identical overall dimensions and flexural steel reinforcement, underwent testing until failure, under the influence of concentrated patch loads. A concrete plastic damage constitutive model (CDP) was developed and employed to examine the strength of two-way RC slabs. Additionally, to enhance the strength of existing RC slabs, carbon fiber reinforced polymer (CFRP) strips are affixed to the tension surface of the sections. The research begins with the calibration of a numerical model, based on data from laboratory tests. The objective of this study is to constrain the plastic behavior of two-way RC slabs reinforced with CFRP, with a focus on establishing an optimal elasto-plastic analysis, aimed at controlling concrete damage plasticity using CFRP, and employing a plastic limit load multiplier. Subsequently, a series of numerical simulations, incorporating different variables, are conducted to investigate shear behavior. The numerical results indicate that an increase in the strengthening ratio has a significant impact on shear strength. Finite element simulations are carried out using Abaqus CAE^®/2018.