钢筋混凝土结构的耐久性和服役寿命预测（英文）

Durability and Service Life Prediction of Reinforced Concrete Structures

介绍了钢筋混凝土结构在氯离子渗透、碳化和冻融侵蚀作用下的耐久性和服役寿命预测模型。过去几年有关组织或国际学术委员会提出了大量的混凝土结构耐久性设计模型。为了在混凝土结构耐久性设计过程中，能够安全地使用此类模型，需要通过分析和比较长期暴露在不同气候条件下的混凝土劣化现场数据，对预测模型的可用性进行验证。在本文中，对混凝土抗氯离子渗透、碳化和冻融侵蚀的各种模型进行了简要阐述。通过暴露时间超过20年的露天场数据，以及约使用了30年的公路桥的现场数据，对包括简单ERFC模型、DuraCrete模型和ClinConc模型在内的3种氯离子渗透模型进行了评估。同时，使用暴露11年的露天场所的现场数据和7～13年的现有建筑的有限数据对一种预测混凝土碳化深度的物理化学模型进行了评价。针对冻融侵蚀的模型，讨论了临界饱和度测量和实际的饱和度测量中的一些问题。根据对结果的比较，可以发现在大多数情况下，简单ERFC模型在大多数情况下对氯离子渗透的预测值高于实际值，而DuraCrete模型的预测值偏低。另外，ClinConc模型对短期f1年）和长期（21年）暴露条件下的预测更合理，预测效果更好。与在挪威获得的暴露级别为XC3现场数据比较，发现Papadakis碳化模型可以较好地预测碳化深度；但是，与暴露级别为XC4级的现场数据比较发现，该模型低估了碳化深度。

This paper presents some durability and service life models for reinforced concrete structures with regard to chloride ingress, carbonation and frost attack. In the past years a number of models for durability design of concrete structures have been suggested by relevant organisations or international committees. It is necessary to validate these models against long-term field data for their applicability with respect to exposure climate in order to satisfactorily use the models in the durability design and redesign of concrete structures. In this study, various potential models for concrete resistance to chloride ingress, carbonation and frost attack were briefly reviewed. Three models including the simple ERFC, the DuraCrete and the ClinConc, for prediction of chloride ingress were evaluated using the infield data collected from both the field exposure site after over 20 years exposure and the real road bridges of about 30 years old. A physicochemical model for prediction of carbonation depth was evaluated using the infield data collected from the field exposure site after 11 years exposure and the limited data from the real structures with the age of 7-13 years. For the modelling of frost attack, some problems in measurement of critical saturation degree and actual degree of saturation are discussed. According to the comparison results, the simple ERFC overestimates whilst the DuraCrete model underestimate the chloride ingress in most cases. The ClinConc model on the other hand gives reasonable good prediction for both the short-term （one year） and the lung-term （21 years） exposure. The Papadakis model for carbonation also gives fairly good prediction of carbonation depth when compared with the Norwegian infield data classified as exposure class XC3, but underestimates the carbonation depths whencompared with the infield data from Norwegian structures in exposure class XC4.