基于延寿-减碳目标的混凝土结构耐久性控制策略研究

Research on durability control strategy of concrete structures based on life-prolonging and carbon reduction objectives

延长结构服役寿命是减少结构全寿命周期碳排放的有效途径。提出了一种综合考虑混凝土结构服役寿命和碳排放的耐久性控制策略分析方法。基于可靠性理论,考虑混凝土结构耐久性能劣化过程三个阶段的规律,研究不同耐久性控制策略对结构可靠度的影响,建立了基于混凝土结构耐久性控制策略的寿命计算模型和碳排放计算模型,提出了描述结构减碳效果的量化指标。通过比较不同耐久性维护和修复方法的延寿效果和碳排放组成,针对工程案例,分别考虑结构的建成状态和既有状态,计算获得不同耐久性控制策略下的服役寿命和年均碳排放量,对比不同策略的延寿和减碳效果。结果表明,耐久性控制策略最高可延长案例结构约22年的服役寿命,并获得8.76%的减碳收益率,在工程实践中应尽早对混凝土结构采取耐久性控制策略以更好地实现结构延寿-减碳目标。

Extending the service life of concrete structures is an effective way to reduce the average annual carbon emission during the life-cycle of structures.An analysis method of durability control strategy considering the service life and carbon emission of concrete structures was proposed.Based on the reliability theory,three stages of deterioration process of concrete structure durability were considered,the influence of different durability control strategies on the reliability of concrete structures was studied,and the life calculation model and carbon emission calculation model of the durability control strategy of concrete structures were established.The quantitative index describing the effect of structural carbon reduction was put forward.By comparing the life-prolonging effect and carbon emission composition of different durability maintenance and repair methods,the service life and average annual carbon emission under different durability control strategies were calculated by considering the construction state and existing state of the structure respectively,and the life-prolonging and carbon reduction effects of different strategies were compared.The results show that the durability control strategy can extend the service life of the case structure by about 22 years and achieve 8.76%carbon reduction rate.In engineering practice,durability control strategies should be adopted for concrete structures as soon as possible in order to achieve better life-prolonging and carbon reduction effect.