Test study on size effect of flexural capacity of RC simple beams

Many studies on size effect of quasi-brittle materials such as concrete and mortar have been carried out. But experimental study and theoretical analysis combining with concrete structure or component is not sufficient, and related theory is not verified fully. This paper collects test information of five different section size samples in different loading stage, including bearing capacity, deflection, section strain and so on. The total number of specimens is 13. This can help to revise related design theories. The safety of related bearing capacity formula is verified in research scale, but safety reserve of calculation theory shows a trend of decrease with specimen dimension increasing. As for large-size bending specimens, size effect of concrete material is reflected in mechanical properties of reinforced concrete structures, the code value of ultimate strain under non-uniform compression is bigger than test value. It is also found that size affect of components have more influence on beam than size affect of concrete materials.