Bond-slip model considering freeze-thaw damage effect of concrete and its application. (15th December 2019)

• Record Type: Journal Article
• Authors: Wang, Zhuo-Han; Li, Lei; Zhang, Yi-Xin; Wang, Wen-Tao
• Is Part Of: Engineering structures. Volume 201(2019)
• Publication Date: 2019-12-15
• Subjects: Freeze-thaw damaged reinforced concrete column -- Freeze-thaw damage -- Bond-slip model -- Steel stress-slip model -- Fiber beam-column element model -- Seismic performance; Structural engineering -- Periodicals; Structural analysis (Engineering) -- Periodicals; Construction, Technique de la -- Périodiques; Génie parasismique -- Périodiques; Pression du vent -- Périodiques; Earthquake engineering; Structural engineering; Wind-pressure; Periodicals; 624.105
• DOI: 10.1016/j.engstruct.2019.109831
• Languages: English
• ISSNs: 0141-0296

Abstract

Highlights: A bond-slip model considering freeze-thaw damage effect of concrete is developed. The proposed model incorporates most factors considered, including freeze-thaw damage level of concrete, concrete properties, rebar properties, and transverse confinements. A steel stress-slip model is derived from the proposed model. The steel model is implemented into a fiber beam-column model using the zero-length section element in OpenSees. The seismic performance of the frozen-thawed reinforced concrete column is modeled by the proposed fiber model. Abstract: The bonding behavior between concrete and steel bar may be severely deteriorated due to freeze-thaw damage of concrete, which may significantly affect the seismic performance of the reinforced concrete structures. This paper presents a novel bond-slip model considering freeze-thaw damage effect of concrete and apply it into the fiber model. The proposed model is developed by modifying an existing bond-slip model to consider the freeze-thaw damage effect of the concrete. The freeze-thaw damage effect of the concrete on the bond behavior is considered to be caused by the deterioration of both material strength and cover confinement of the concrete. The reliability and accuracy of the proposed model in capturing the freeze-thaw damage effect of the concrete on the bond stress-slip relationship are verified by comparison with pull-out tests data and existing models. Then, the steel stress-slip model is derived from the proposed bond-slip model based on the infinitesimal procedure. The derived steel stress-slip model is implemented into a fiber model that considers the freeze-thaw induced uneven damage along the member section. The general framework for applying the proposed model to a fiber beam-column element model is established. The proposed fiber model is validated by the experimental results and existing fiber model without incorporating the bond-slip effect. Excellent accuracy is observed between the model results and the experimental results. The fiber model without incorporating the bond-slip effect may overestimate the seismic performance of the freeze-thaw damaged reinforced concrete column. The results confirm that the proposed fiber model can comprehensively incorporate the degradation of uneven material strength and the deterioration of the bond behavior due to freeze-thaw damage effect of concrete.