Effect of Initial Load on the Mechanical Properties of Concrete Beam Strengthened with Extraneous Prestress

In order to study the effect of initial load on the mechanical properties of concrete beam strengthened with extraneous prestress, contrastive experiments were conducted on three reinforced concrete beams with different initial loads. The results indicate that the mechanical properties of the three beams are different. The cracking of reinforced concrete due to the initial loads badly weakens the rigidity of the reinforced concrete structure. Under the same increment in load, the greater the initial load is, the smaller the rigidity of the reinforced concrete beams becomes. The calculation methods of deflection and split of reinforced concrete beam are proposed.