[en] Reinforced concrete dapped-end connections are commonly used in precast structures due to ease of construction and the possibility to maintain a reduced structural depth. However, dapped-end connections typically feature inclined corner cracks at service loads due to stress concentrations at the re-entrant corner. Furthermore, these connections transfer high shear forces through a significantly reduced section. Due to these reasons, two main failure modes of dapped-end connections are identified as failures along a re-entrant corner crack and shear failures in the dapped-end region. This paper investigates such failure modes through an experimental campaign consisting of eight large-scale dapped-end tests. The main test variables are the amount of dapped-end reinforcement and the ratio of dapped-end horizontal to vertical reinforcement area. Detailed deformation measurements and an in-depth discussion on the behavior of the test specimens is presented. The effect of the test variables on the strength, crack control and rotation capacity of dapped-end connections is investigated. It was found that, for the same total area of horizontal and vertical reinforcement, connections featuring more horizontal reinforcement are stronger. While the orthogonal dapped-end reinforcement layout did not provide sufficient crack control under service loads, all connections exhibited substantial rotation capacity, including the shear critical connections. The flow of internal forces of the test specimens is further studied with a kinematics-based model and nonlinear finite element analysis.
Disciplines :
Civil engineering
Author, co-author :
Rajapakse Mudiyanselage, Chathura Madushanka ; Université de Liège - ULiège > Département ArGEnCo > Structures en béton ; UHasselt - Hasselt University [BE] > Department of Industrial Engineering
Degée, Hervé; UHasselt - Hasselt University [BE] > Department of Industrial Engineering > Professor
Mihaylov, Boyan ; Université de Liège - ULiège > Urban and Environmental Engineering
Language :
English
Title :
Investigation of shear and flexural failures of dapped-end connections with orthogonal reinforcement
This research was funded by BOF 2018: Doctoraatsfonds i.s.m. ULi?ge: Chathura Rajapakse [Grant Number BOF 2018 -BOF18DOCLI02 - cofin UHasselt-ULiege]. The authors would like to express their gratitude to the Applicatiecentrum Beton en Bouw (structural laboratory) at Hasselt University, where the tests were conducted. The excellent support of Ing. Dan Dragan in conducting the tests, and Dr. Rik Steensels during design and procurement of the specimens is greatly appreciated.
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