兩端束制RC梁抵抗漸進式崩塌行為之試驗研究

An experimental study on the resistant behavior of constraint RC beams against progressive collapse

黃博鴻(Po-Hung Huang)

指導教授 ： 蔡孟豪

國立屏東科技大學/工學院/土木工程系所/碩士(2013年)

https://doi.org/10.6346/NPUST.2013.00042

摘要

在2001年美國911恐怖攻擊事件發生後，建築結構抵抗漸進式崩塌的能力頓時成為世界各國主要的研究課題之一。結構物底層柱遭到破壞後，該柱原本所承受的荷重是否能透過上方的增跨梁重新分配，影響著結構物是否有足夠的抵抗漸進式崩塌之強度。一般RC建築物中，梁內主筋可分為連續及不連續兩種配置；而在不同配置下對於鏈索效應及壓拱效應的影響尚無明確的研究。故本文主要針對上述情形，以梁內配筋變化設計兩跨的梁柱模型進行靜力加載試驗，探討梁內鋼筋配置之變化對於鏈索效應之影響。試驗結果所獲得之數據可明確的了解鏈索效應發展之行為；在梁內鋼筋採連續筋配置時，鋼筋比越低則越容易發展出鏈索效應之行為，若在梁內受拉區增設鋼筋，在試體發展鏈索效應時，因增設鋼筋為斷筋配置，當試體產生裂縫後導致增設鋼筋滑脫而無法有效地提供其抗拉強度；若梁端周圍構件無法提供邊界條件約束時，則不利於鏈索效應之發展。

關鍵字

漸進式崩塌 ； 鏈索效應 ； 壓拱效應 ； 靜力試驗

並列摘要

In this study, an experimental program was conducted for investigating progressive collapse resistance of reinforced concrete beam-column sub-assemblages with varied bar-cutoff patterns under a middle column removal scenario. The load was applied onto the middle joint through a hydraulic actuator with displacement control until the specimens completely failed by reinforcements fracture. Results indicate that the implemented static test is a viable method to simulate progressive collapse by arch action and catenary action. From the load-displacement response of three specimens designed with continuous main reinforcements, it is realized that contribution of catenary action to collapse resistance may be increased with decreased steel ratio. The test results of four specimens designed with varied bar-cutoff patterns indicate that the catenary action is insensitive to increases flexural reinforcements in the beam-end and middle joint of tension regions due to bond-slip behavior occurred. And the effect of catenary action also decreased as loss the constraint for lateral movement.

並列關鍵字

Progressive collapse ； catenary action ； arch action ； static test

參考文獻

1.ASCE/SEI 7-05, Minimum Design Loads for Buildings and Other Structures, Structural Engineering Institute, American Society of Civil Engineers, Reston, VA, 2005.

2.Pearson, C., and Delatte, N., “Ronan Point Apartment Tower Collapse and its Effect on Building Codes,” Journal of Performance of Constructed Facilities, ASCE, Vol.19, No.2, pp.172-177,2005.

3.Osteraas, J.D., “Murrah Building Bombing Revisited: A Qualitative Assessment of Blast Damage and Collapse Patterns,” Journal of Performance of Constructed Facilities, ASCE, Vol. 20, No. 4, pp. 330-335, 2006.

4.Choi, J.H., and Chang, D.K., “Prevention of Progressive Collapse for Building Ssructures to Mmmber Disappearance by Accidental Actions,” Journal of Loss Prevention in the Process Industries, Vol. 22, pp. 1016-1019.

5.ACI Committee 318, “Building Code Requirements for Structure Concrete (ACI 318-02) and Commentary (ACI 318R-02),” American Concrete Institute, Farmington Hills, 2002.