【摘要】 依据混凝土保护层碳化寿命准则和钢筋锈胀开裂寿命准则,建立了预应力混凝土梁桥耐久性寿命计算模型,并采用计算时变可靠度指标的方法,研究了处在一般大气环境下一预应力混凝土梁桥的耐久性寿命。计算结果表明:该桥主梁在桥梁服役28年后达到其混凝土保护层碳化寿命,混凝土保护层碳化寿命的可靠指标在桥梁服役初期下降较快,后期下降较慢;在桥梁服役96年后达到钢筋锈胀开裂寿命,说明在一般大气环境中的预应力混凝土梁桥,若混凝土强度较高且只考虑混凝土碳化引起桥梁抗力衰减时,可不考虑钢筋锈蚀对桥梁承载能力的影响。更多还原

【Abstract】 The model to calculate the durability life of prestressed concrete bridge was built based on the principle of concrete carbonation life and the principle of concrete cracking life. The method of the calculating time-varied reliability indicator was introduced. The durability life of prestressed concrete in common environment was studied with this method. The result revealed that the carbonization life of the bridge was 28 years and the cracking life of the bridge was96 years. The indicator of concrete carbonation life decreased drastically at the initial stage,and decreased slowly at the last stage. The result also suggested that the effect of the corrosion of the steel bars on the strength of the bridge was trivial ifthe concrete carbonation leading to the attenuation of bridge resistance was only take into account when the compression strength of concrete was high.更多还原