既有钢筋混凝土Π梁正截面抗弯承载力研究-中南大学学报.PDF

42 2 () Vol.42 No.2 2011 2 Journal of Central South University (Science and Technology) Feb. 2011 Π ( 410114) Π Π Π Π40 a Π U445.73 A 1672−7207(2011)02−0456−07 Flexural bearing capacity of existing reinforced concrete Π beams LÜ Yi-gang, ZHANG Jian-ren, PENG Hui, ZHANG Ke-bo (School of Civil Engineering and Architecture, Changsha University of Science Technology, Changsha 410114, China) Abstract: On the basis of the incorrectness of the plane-section assumption, reinforced concrete Π beams was taken as the research object and the variation law of the bearing capacity of beams was established with different corrosion rates. By constructing the new deformation compatibility, the calculation formula of the compression depth of existing reinforced concrete Π beams varying with corrosion rate was presented, and the calculation formula of normal section capacity of existing reinforced concrete Π beams was derivered. Based on these analyses, the presented formula verifies the calculation formula of the flexural capacity using the experimental data for perimeters of material quality and damage loads obtained from a real bridge that served for about 40 years. The results indicate that the computational results of the calculation formula are in good agreement with the experimental results, which shows that the calculation formula of flexural capacity is effective and can be applied in engineering practice. Key words: reinforced concrete beams; corrosion; flexural bearing capacity; depth of compression z