Development of Macro-Modeling Method for In- and Out-of- Plane Failure of URM Infill Wall

2021 Fiscal Year Annual Research Report

• Project/Area Number: 21J22394
• Allocation Type: Single-year Grants
• Research Institution: The University of Tokyo
• Principal Investigator: Adnan S M Naheed 東京大学, 工学系研究科, 特別研究員(DC1)
• Project Period (FY): 2021-04-28 – 2024-03-31
• Keywords: URM infill / Out-of-plane behavior / Numerical model

Outline of Annual Research Achievements

The focus of the research is to simulate the out-of-plane behavior of unreinforced masonry (URM) infills. A typical 6-story building in Bangladesh is analyzed under expected ground motion in Dhaka city. We have designed and constructed full-scale brick URM infilled RC frame specimens which represent a frame on the top story of the assumed prototype building. By conducting a dynamic analysis of the building, the excitation that will be suffered by the selected frame in the out-of-plane direction is derived. This excitation will be used as the reference excitation to apply out-of-plane shaking to the specimens.
In-plane testing of the two URM infilled RC frame specimens have been conducted. The first specimen is tested for up to 1.00% in-plane drift and 0.40% in-plane drift is applied to the second specimen. The first specimen is moved to the shaking table and the measurement system for the out-of-plane shaking test has been set up. A numerical model to predict the out-of-plane behavior of the URM infill specimens is under development. We will conduct the out-of-plane shaking test after the development of the numerical model to compare the numerical and experimental results.

Current Status of Research Progress

2: Research has progressed on the whole more than it was originally planned.

Reason

The progress of the research can be defined as "generally progressing steadily". We have already designed and constructed the specimens and applied in-plane loading to the specimens. The measurement system for the out-of-plane shaking test has also been set up. A numerical prediction model for the out-of-plane behavior of the URM infills is under development. Hence, we are steadily progressing towards the next stage of the research, which is to compare the numerical and experimental results and identify the factors making differences between them and accommodate those factors in the numerical model.

Strategy for Future Research Activity

A numerical prediction model for the URM infills in the out-of-plane direction is under development. We will conduct the out-of-plane shaking test after the model is finalized. Afterward, the prediction results and the experimental results will be compared. If there are differences between the results, the reasons behind the differences will be identified and the numerical model will be modified accordingly. In addition, a scheme to implement the numerical prediction model of the out-of-plane behavior of URM infills in a building structure analysis will be proposed.