Cracking moment of rectangular reinforced concrete sections corresponding to the bilinear stress strain diagram of concrete = Tính toán mô men kháng nứt của tiết diện dầm bê tông cốt thép ứng với môn hình ứng xử phi tuyến song tuyến tính của bê tông

Abstract

This paper develops an improved analytical formula for determining the cracking moment of rectangular reinforced concrete sections, incorporating the nonlinear behavior of concrete modeled by a bilinear stress-strain diagram in accordance with TCVN 5574:2018. The proposed formula has been experimentally validated, with errors mostly below 7%. Parametric analysis reveals that the cracking moment increases linearly with both tensile and compressive reinforcement ratios, with tensile reinforcement having a dominant influence. Moreover, the simplified approach in TCVN 5574:2018 significantly underestimates the cracking moment, especially at high tensile reinforcement ratios.