明架式輕鋼架天花板之斜撐組耐震分析及天花板受垂直向地震研究

Seismic Analysis of Ceiling Lateral Bracing and Vertical Motion Effects on Suspended Ceilings

10.6849/SE.201703_32(1).0005

陳威中(Wei-Chung Chen)；姚昭智(George C Yao)；林經堯(Ching-Yao Lin)

懸吊式輕鋼架天花板 ； 明架式天花板 ； 斜撐組 ； 垂直向地震 ； 振動台實驗 ； suspended ceilings ； lateral bracing assembly ； bracing wire ； shaking table experiment ； vertical motion

結構工程

32卷1期（2017 / 03 / 01）

100 - 124

繁體中文

歷年來國內外之地震勘災紀錄可以知道， 在建築物主結構系統尚未發生破壞之情況下，非結構物遭受嚴重破壞的例子很多，而各項非結構物之損壞又以明架式天花板之破壞最為常見。明架式天花板為國內極為普遍之懸吊式天花板系統，卻因缺乏適當之施工方式及耐震措施導致在地震中極容易受到損壞。2011年明架式天花板之耐震施工指南正式收入至「建築物耐震設計規範及解說」之附錄B 中，其中作為抵抗水平地震力之耐震措施即為斜撐組之設置。然而斜撐組之施作一直以來都面臨極大的施工問題，造成許多斜撐組並無法於現場順利組裝，以致於天花板耐震品質參差不齊，影響原訂規範之美意。近年來陸續有研究發現斜撐組並無法有效抵抗地震之作用，甚至有實驗顯示當垂直地震力同時被考慮時反而會加重天花板破壞之情況。為確實瞭解垂直向地震對於明架式天花板之影響以及斜撐組之實際效用，本研究規劃兩階段之全尺寸天花板振動台試驗，試體材料皆符合規範之耐震需求。第一階段天花板試體尺寸為5.7m×2.7m，此階段主要為量測天花板斜撐組在地震中所能負擔之地震力大小，部分試體以單一水平向震波進行測試，其餘天花板試體則同時輸入水平向及垂直向震波。實驗結果發現不論是否考慮垂直向振動，斜撐組中之斜拉線均僅能負擔極少部分之水平作用力（約3%至5%），而當垂直向振動作用於天花板試體時其斜拉線之效用則更為下降。第二階段天花板試體尺寸為7.3m×2.7m， 此階段目的為觀察天花板試體在不同方向地震作用下之破壞模式，實驗結果顯示不論天花板試體是否裝設斜撐組，在單一水平向地震作用下皆有極佳之耐震效果；然而一旦加入垂直向地震力，天花板骨架接頭及骨架收邊處則陸續會出現明顯破壞，甚至在有設置斜撐組之天花板試體中會發現因垂直懸吊線脫落而導致試體發生嚴重崩塌的情形，也說明斜撐組之設計並無法有效提升明架式天花板之耐震能力。本研究依據第二階段實驗數據利用SAP2000 建置明架式天花板電腦模型，首先透過模態分析確認電腦模型之合理性，再以實驗地震紀錄進行動力歷時分析比對電腦模型輸出反應與實驗量測值。完成後之天花板電腦模型可作為後續研究之用模擬各式不同條件明架式天花板之地震動態反應。

Past earthquakes have shown widespread damage to the suspended ceilings. Despite their frequent use in Taiwan, many suspended ceilings experienced damage in earthquakes owing to the lacked proper seismic design or efficient installation. In 2011, Taiwan Building Code issued the seismic installation of the suspended ceiling systems which are similar to the ASTM E580-09. However, the construction of the lateral bracing assembly has always been a difficult challenge. Problems include slack installation or omission of the bracing wires due to obstructions result in uneven quality of the bracing system in-situ. In recent years, some researches have demonstrated that the lateral bracing assembly may not adequately resist the lateral force. The other researches have even shown that unbraced ceiling systems may perform well when providing both sufficient clearance and wide closure. Therefore, there is an increasing concern about the necessity of the bracing system. In order to understand the dynamic behavior of bracing systems of the suspended ceilings, full scale shaking table experiments of suspended ceiling systems were conducted in this study. The first series of experiments on 5.7m × 2.7m ceiling systems looked into the seismic effects of the bracing assemblies. Some ceiling specimens were subjected to unidirectional ground motions while the others were subjected to a horizontal and a vertical ground motions acting together. The results clearly showed that the bracing wire bore only a small portion of the inertial force, and this situation became more obvious while the ceiling systems were subjected to vertical excitations. The second series of experiments on 5.7m × 2.7m ceiling systems compared the seismic performance of the braced and unbraced ceilings. The preliminary observations revealed that the use of the lateral bracing including compression post may not improve the seismic performance of the ceiling system. The unbraced ceiling systems performed well just as the braced ceiling systems when excited only by horizontal ground motions, and it performed better when the vertical ground motions were added to the ceiling systems. In this study, a conceptual computer model was developed based on the experiment data. The accuracy of the computer model was verified by using modal analysis. In comparison with the experiment results, this computer model provides the time-history analysis with reliable accuracy and helps simulate the dynamic response of different conditions of ceiling systems.

1. (2010).Standard Practice for Installation of Ceiling Suspension Systems for Acoustical Tile and Lay-in Panels in Areas Subject to Earthquake Ground Motions.ASTM International.
2. (2007).Standard Specification for the Manufacture, Performance, and Testing of Metal Suspension Systems for Acoustical Tile and Lay-in Panels Ceilings.ASTM Internationa.
3. ANCO(1983).,Culver City, CA:.
4. ASCE(2010).Minimum Design Loads for Buildings and Other Structures. ASCE 7-10, American Society of Civil Engineers.NY, USA:
5. Badillo, H.,Whittaker, A.S.,Reinhorn, A.M.(2007).Seismic Fragility of Suspended Ceiling Systems.Earthquake Spectra,23(1),21-40.
6. Benuska, Lee(1990).Loma Prieta earthquake reconnaissance report.Earthquake Spectra,Supplement 6,339-377.
7. Gilani, A. SJ.,Takhirov, S.,Tedesco, L.(2013).Seismic Evaluation of Suspended Ceiling Systems Using Static and Dynamic Procedures.Proceeding of 44th Structures Congress,Pittsburg, PA.:
8. Lawrence Livermore Laboratory(1980).,USA:.
9. Reinhorn, A.M.(2000).Design and development of testing frame for suspended ceilings.
10. Rihal, S.,Granneman, G..(1984).,Pomona, CA.:California Polytechnic State University.
11. Soroushian, S.,Maragakis, E. M.,Itani, M.,Pekcan, G.,Zaghi, A. E.(2011).Design of a Test Bed Structure for Shake Table Simulation of the Seismic Performance of Nonstructural Systems, Structures Congress.Proceeding of 42nd Structures Congress,Las Vegas, USA.:
12. Soroushian, S.,Ryan, K. L.,Maragakis, E. M.,Sato, E.,Sasaki, T.,Okazaki, T.,Tedesco, L.,Zaghi, A. E.,Mosqueda, G.,Alvarez, D.(2012).Seismic Response of Ceiling/Sprinkler Piping Nonstructural Systems in NEES TIPS/NEES Nonstructural/NIED Collaborative Tests on a Full Scale 5-Story Building.Proceeding of 43th Structures Congress,Chicago, USA:
13. Taniguchi-Ruth-Smith Associates(1993)。Taniguchi-Ruth-Smith Associates (1993). Guam Memorial Hospital Earthquake Damage Report, Cloria J.Long的私人通訊。
14. Yao, G.C.(2000).Seismic Performance of Direct Hung Suspended Ceiling Systems.J. of Architectural Engineering,6(1),6-11.
15. 內政部建築研究所(1998).嘉義瑞里地震建築災害調查報告書.台北:
16. 內政部營建署編輯委員會（2011）。建築物耐震設計規範及解說。台北：中華民國內政部營建署。
17. 倪伯聰(1998)。台南，國立成功大學建築研究所。
18. 許茂雄(1999)。一九九九集集大地震災害調查研討會論文集，台北:
19. 鍾育霖(2001)。台南，國立成功大學建築研究所。