Analytical investigations for in-situ testing of non-ductile RC buildings

Abstract

In order to perform an in-situ pushover test on a real, existing building, a test setup developed via a comprehensive study is required. The scope of this study is to propose a test setup for in-situ testing of a typical reinforced concrete building constructed in Turkey in the 1970’s. First of all, previous research on field and laboratory testing of different strengthening methods and nonlinear analytical modeling techniques in the literature are investigated. The accuracy of available nonlinear modeling techniques are evaluated by analyzing a typical Taiwanese school building, namely the Hsin-Tseng Junior High School building, and comparing analysis results with experimental results by Tu et al.[1]. It is observed that material properties, cracked section stiffnesses, building geometry, existence of windowsills, and nonlinear modeling techniques selected affect the results of the analyses significantly. Sehit Adem Yavuz Primary School in Istanbul is chosen as a case-study building and an in-situ testing scheme is proposed for the building. By using geometrical properties and material properties of the case building, a preliminary test setup is proposed. The proposed setup comprises testing of four 2-storey-single bay test frames, including (i) a bare frame, (ii) an infilled frame, (iii) an infilled frame strengthened with Carbon-Fiber-Reinforced- Polymers, and (iv) a frame with reinforced concrete infill wall. In the light of the analytical modeling techniques investigated, the proposed tests are analyzed via nonlinear static pushover analyses conducted using commercial computer software program SAP2000 v11.0.0 for blind prediction of the test results. The behavior of the test frames are examined in terms of lateral load-lateral displacement responses and hinge formation sequences. The final test setup for the in-situ tests is developed in accordance with the analyses results. For the proposed tests, the proposed construction work needs to be conducted before testing. Hydraulic loading equipment, load cells, assemblage systems for test frames and reaction block, out of plane resistant frame systems, reference columns for measurements, displacement sensors, and data acquisition systems necessary for testing are also identified.