竜巻および竜巻飛来物に起因した都市部の重要構造物に対する被害評価法に関する研究

2016 Fiscal Year Annual Research Report

• Project/Area Number: 15F15749
• Research Institution: Kyoto University
• Principal Investigator: 八木 知己 京都大学, 工学研究科, 教授 (30293905)
• Co-Investigator(Kenkyū-buntansha): NASSR AMR 京都大学, 工学研究科, 外国人特別研究員
• Project Period (FY): 2015-10-09 – 2018-03-31
• Keywords: 風災害 / 飛散物 / ガラス繊維強化プラスチック / 合わせガラス / 衝撃荷重 / 過渡応答 / 波動伝播

Outline of Annual Research Achievements

In this study, the vulnerability of structural and non-structural elements to wind-borne debris has been investigated. In this regard, an experimental program of testing 24 Glass Fiber Reinforced Polymers (GFRP) panels and 16 Laminated Glass (LG) panels has been conducted using an air cannon device capable of launching different projectiles with velocities up to 100 m/s. The dynamic transient impact response has been measured using a number of strain gauges located at various locations on panels’ surfaces. Different parameters have been varied including, impactor size/mass, impactor velocity, and material compositions. In addition, Finite Element Models (FEM) of impacted panels has been constructed. The models have taken into account material orthogonality and strain-rate dependent behavior. By analyzing the transient response, it was found that the response was governed by elastic wave propagation characteristics; the flexural wave was predominant propagating with different velocities in different directions, depending on the material elastic properties of their directions. In addition, low amplitude longitudinal waves were also observed. The impact velocity showed a pronounced influence on the measured strains and strain rates.

Current Status of Research Progress

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

Reason

During the last year, it was planned to conduct the experimental phase of this study. In this regard, all GFRP and LG panels were obtained from material suppliers. The instrumentations (strain gauges) necessary for measuring the dynamic response of test panels under impact were purchased. Data collecting system with a high sampling frequency was rented. The test panels and test setup of air cannon device were prepared. All parameters planned for this test was successfully conducted. The data of GFRP panels were analyzed and written in a journal paper submitted to International Journal of Impact Engineering. In addition, numerical models of the impacted panels have been conducted and used to explore several parameters. The results of the numerical models have been written in a conference paper and submitted to 12th International Conference on Shock & Impact (to be held in June 2017). Moreover, Dr. Nassr attended and participated in 4th International Conference of Protective Structures in Beijing, China. In overall, almost all research goals planned for the last year were met and the research progress is considered to be satisfactory.

Strategy for Future Research Activity

It is expected that for the remaining period of the fellowship (April 1- August 31) that data of the GL panels will be analyzed and written in a paper to be submitted to an international journal related to the field. In order to obtain the static properties of GFRP and GL materials, a series of material testing will be conducted. In addition, Dr. Nassr will present his research at 12th International Conference on Shock & Impact Loads on Structures held in Singapore from 14-16 June and at 16th International Conference on Fracture and Damage Mechanics held in Italy from 18-20 July.