为了研究锈蚀梁粘贴钢板加固后可靠指标的提高量,依托锈蚀梁加固前后承载力试验研究,根据锈蚀钢筋与混凝土的粘结系数以及9根锈蚀后加固试验梁的实测弯矩值,拟合了钢板与锈蚀RC梁的协同工作系数。根据拟合结果建立了锈蚀梁加固完成时抗力计算模型,依据误差传递公式得出了抗力的均值和方差的计算公式,用JC法迭代计算了锈蚀梁加固前后可靠指标提高量,计算对比分析了保护层厚度、钢筋锈蚀率和加固钢板厚度对可靠度提升的影响,并进行了参数敏感性分析。研究结果表明,保护层厚度和钢筋锈蚀率对锈蚀梁可靠指标提高量影响较小;钢板厚度对结构可靠指标提高量影响较大,板厚从3 mm变到5mm,结构可靠指标提高量增加了近1倍。
According to the adhesive coefficient of corrosion RC beams,as well as the tested bending moment of nine tested beams,based on the tested results of flexural capacity of corroded beams,the collaborative work coefficients of the steel plate and the corroded RC beams are fitted and the resistance assessment model of corroded beam with/without strengthened by bonded steel plate are developed.Using error transition function,the calculation equations of mean value and coefficient of variation for structural resistance are obtained.The JC method is used to calculate the improvement of reliability indicator of corroded beam with/without strengthened by steel plate.The influences of cover,corrosion rate and steel plate depth on the improvement of reliability indicator of corroded beam are performed and the parametric sensitivity analysis is conducted.It is indicated from calculated results that there are few influences of cover and corrosion rate on the improvement of reliability index and there is a larger influence of depth of steel plate on improvement of reliability indicator.When the depth of steel plate varies from 3mm to 5mm,the improvement ofreliability indicator increased nearly 1 times.