“Experimental and Analytical Investigation of Bond Strength in M20 and M30 Grade Concrete Using Pullout Test”

The bond between reinforcing steel and concrete is a fundamental factor governing the strength, durability, and serviceability of reinforced concrete structures. This study investigates the bond strength of M20 and M30 grade concrete using both experimental and analytical approaches. The experimental work involves conducting pullout tests on concrete specimens embedded with steel reinforcement bars to evaluate the load–displacement behavior and ultimate bond strength. Analytical modeling is carried out using finite element software ANSYS to simulate the bond interaction and validate experimental results. The study examines the influence of concrete grade on bond performance and compares the experimental outcomes with analytical predictions. Results indicate that higher grade concrete exhibits improved bond strength due to better mechanical interlocking and adhesion properties. The load–displacement curves obtained from both methods show similar trends, confirming the reliability of the analytical model. Additionally, different bond failure modes such as pullout failure and bond slip are identified and analyzed. The findings contribute to better understanding of bond behavior and support improved design and construction practices in reinforced concrete structures.