自來水管線力學試驗與非線性側推分析之研究

Tests and Nonlinear Pushover Analysis of Water Pipeline

郭峻瑋(Chun-Wei Kuo)

指導教授 ： 鍾立來

國立臺灣大學/工學院/土木工程學研究所/碩士(2012年)

https://doi.org/10.6342/NTU.2012.03206

摘要

台灣位處環太平洋地震帶，平均數十年會發生一次嚴重性的陸上地震，當地震發生時，不論是地上或地下結構物，將面臨嚴峻的考驗，不只是斷層本身造成的災害，因為地震而發生土壤液化危害，也將會對整個地下自來水管線造成嚴重的影響，由於自來水管線屬於維生管線系統，倘因震害無法運作、提供穩定的服務時，勢必對於民生需求以及衛生環境造成一大衝擊，隨之而來的社會安定問題，對於震後的社會又再是另一波的動盪，因此對於自來水管線受地震所引起的損害，是現今進步社會的一項重要課題。
本研究主要方向可分為兩部分，第一部分為延性鑄鐵管(Ductile Iron Pipes , DIP)與K型接頭力學試驗，延性鑄鐵管為台灣常用地下水自來管線，具有高強度、高延展性、安全性高等優點；而K型柔性接頭則是利用壓圈緊壓橡膠圈緊達到水密性高以及擁有適度的彎曲等優點，藉著軸向抗壓、軸向抗拉、四點式彎矩試驗三種實驗測試管體與接頭的抗拉力、抗壓力與抗彎矩強度以求得管體與接頭的廣義力與位移關係。
第二部分為進行管線非線性側推分析，在執行側推分析之前，必須先配置非線性塑鉸參數，前人研究中利用材料參數與分析的結果建立軸力與彎矩非線性塑鉸，而本研究則是利用試驗結果與非線性挫屈分析的比對結果，對於非線性壓力塑性鉸重新修正。
總合上述兩部分的結果，利用案例分析探討了延性鑄鐵管DN400mm的管體受平移斷層之行為，考慮容許錯動量以及管線破壞模式，在管線壓力控制模式下可以發現容許錯動量有減少的趨勢，而撓曲與拉力控制的管線則跟前人的研究結果類似。

關鍵字

地下自來水管線 ； 管線試驗 ； 局部挫屈 ； 非線性鉸 ； 地層錯動 ； 側推分析

並列摘要

In this study, the major research direction divides into two parts. One is the tests of ductile iron water pipes with type K joints including axial tension, axial compression and four points bending tests. Another is the nonlinear pushover analysis of continuous ductile iron water pipeline under strike-slip fault.
Ductile iron pipe, which is one of the commonly used water pipeline at Taiwan, has many advantages, such as high strength, ductility and economic and so on. The type K joint utilize rubber and pressing ring to reach high tightness of water and enough bending angle. In this study, three tests of water pipes with joints are carried out to get the relationship curves of tension-displacement, compression-displacement and moment-rotation.
Before carrying out nonlinear pushover analysis of pipelines, nonlinear plastic hinges must be set. In the early literature, material parameter and the analysis of ABAQUS are used to set the axial and moment plastic hinges. In this study, we set the modified axial compression plastic hinges by combing the result of the tests with analysis of nonlinear compression models.
Combing the results of the two parts, we investigate the verifications of pushover analysis under the strike-slip fault by considering allowable fault displacement and failure model of pipes. Under the failure mode controlled by compression and bending of the pipes, the allowable fault displacement tends to decrease. On the other hand, under the failure mode controlled by tension and bending of the pipes, the results of pushover analysis are similar to the early literature.

並列關鍵字

water pipelines tests ； pushover analysis ； plastic hinges ； DIP ； type K joint ； local buckling

參考文獻

[19] 鍾立來、吳賴雲、陳振豪、郭峻瑋、劉季宇、黃國倫，“應用非線性側推分析於地下自來水管線受斷層錯動之研究”，國家地震工程研究中心報告，NCREE-11-026，2011。

[12] 侯信宇，“地下延性鑄鐵管通過斷層之接頭佈設研究”，國立成功大學土木工 程研究所碩士論文，2008。

[1] Tsai, J.S., Jou, L.D. and Lin, S.H., “Damage to buried water supply pipelines in the Chi-Chi(Taiwan) earthquake and a preliminary evaluation of seismic resistance of pipe joints.”, Journal of the Chinese institute of Engineers, vol.23(24), pp. 395-408, 2000.

[13] Joshi, S., Prashant, A., Deb, A. and Jain, S.J., “Analysis of buried pipelines subjected to reverse fault motion,”Soil Dynamics and Earthquake Engineering, 31(7), pp.930-940, 2011.

[17] Wang, L.R.L. and Yeh, Y.H., “A refined seismic analysis and design of buried pipeline for fault movement,” International Journal on Earthquake Engineering and Structural Dynamics, 13(1), pp. 75-96, 1985.