Direct shear resistance models for simulating buried RC roof slabs under airblast-induced ground shock. (1st June 2017)

• Record Type: Journal Article
• Authors: Krauthammer, Theodor; Astarlioglu, Serdar
• Is Part Of: Engineering structures. Volume 140(2017:Jun. 01)
• Page Start: 308
• Page End: 316
• Publication Date: 2017-06-01
• Subjects: Direct shear -- Reinforced concrete -- Buried slabs -- Airblast-induced -- Ground shock; 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.2017.02.056
• Languages: English
• ISSNs: 0141-0296

Abstract

Highlights: Direct shear is a known structural response mechanism in RC slabs subjected to blast loads that may cause their sudden and catastrophic failure. Empirical resistance functions for direct shear in RC elements were introduced in the 1970s, were used since the 1980s. However, the direct shear mechanism in the short-duration dynamic domain has not been sufficiently studied, and it is not clear if those models are accurate. Recent direct shear impact tests were conducted on RC shear specimens, and the results were used to derive modified direct shear resistance functions. The old and new direct shear models were used for the analysis of RC roof slabs subjected to airblast-induced ground shock, and the results were compared. Abstract: Direct shear is a known response mechanism in Reinforced concrete (RC) slabs subjected to blast loads that may cause their sudden and catastrophic failure. It poses a very serious hazard to facilities subjected to blast. The empirical equations defining the direct shear resistance function for RC elements were developed in the 1970s based on results from a limited number of static tests. These equations have been used for the analyses of structural response under blast and ground shock effects since the 1980s. However, the direct shear mechanism in the short-duration dynamic domain has not been sufficiently studied, and it was not clear if those models are accurate. New static and impact test data from shear specimens with three reinforcement ratios were used to derive modified direct shear resistance functions that were different from the resistance functions proposed in the 1970s. One must determine if the new resistance functions could accurately represent the behavior of RC slabs subjected to blast loads. Furthermore, one had to understand the behavioral differences in the numerical simulations that could be associated with the two types of resistance functions, and provide recommendations on how to most appropriately represent direct shear in such analyses. This paper is focused on the assessment of the new direct shear resistance functions in RC, and the results from the parametric study were compared results obtained with the previous empirical direct shear model and with precision field test data to provide conclusions and recommendations.