碼頭棧橋損壞及FRP修復預力混凝土基樁之有限元素分析－使用OpenSees軟體

Finite Element Analysis of Damaged and FRP-repaired PC Piles for Landing Stage Structures using OpenSees Software

陳泓儒(Hung-Ru Chen)

指導教授 ： 鄭全桓

國立暨南國際大學/科技學院/土木工程學系/碩士(2008年)

https://doi.org/10.6837/NCNU.2008.00322

摘要

本文主要探討碼頭棧橋因海洋惡劣環境導致腐蝕損壞而使用纖維強化高分子複合材料(Fiber Reinforces Plastic,FRP)之補強，並使用由美國加州大學柏克萊分校的太平洋地震工程研究中心所開發的物件導向式有限元素分析軟體－OpenSees進行FRP補強後基樁受側向水平載重之反覆載重分析。
本文分析依據力法式有限纖維元素模式建立，在鋼筋混凝土的材料組成律方面，混凝土結構使用修正的Kent及Park模式，鋼筋則考慮到等向性應變硬化行為以及考慮到Baushinger效應。之後針對FRP的材料性質和補強設計方法進行文獻回顧整理，並使用OpenSees模擬FRP補強後基樁受側向力時各階段之力－位移關係。
分析結果比對實驗值，會發現反覆載重初期都有偏高的現象產生，進入反覆載重末期又會低估，但是分析值之最大強度符合實驗值。總體而言，本研究在有限元素側向反覆載重分析仍符合預期目標。

關鍵字

碼頭棧橋 ； FRP ； 預力混凝土基樁 ； 有限元素 ； OpenSees ； 側向反覆載重分析

並列摘要

Corrosion and deterioration of concrete piles are common problems for wharf structures. Wave impacts, cyclic wetting and drying due to tidal action, and high concentration of chlorine ions result in accelerated deterioration of marine concrete piles. Retrofit schemes for corroded marine concrete piles are similar to those for reinforced concrete (RC) columns.
Among the popular retrofit methods, FRP jacketing has been attracting intensive interests in research as well as in practical application. Despite the rapid development of research and application of FRP jacketing for RC column retrofit, study on FRP jacketing for marine concrete piles is rare. As the corrosion condition facing marine piles is much different from that for RC columns, the effectiveness of the retrofit technique for corroded marine piles needs to be re-examined.
A case of corrosion of prestressed concrete (PC) piles supporting landing stage structures in a harbor of Taiwan was investigated. A series of 7 reduce-scaled PC pile specimens simulating the corroded and the FRP-repaired PC piles were tested to investigate the lateral load-carrying behavior of the PC piles for the landing stage structures. The present thesis presents the analytical study on the experiments.

The forced-based finite fiber element (FFE) model that has been built in the OpenSees software framework is employed. Each specimen is modeled by a forced-based FFE, which consists of 8 controlled cross sections. Each of the controlled sections is sub-divided into a number of fibers that represent the stress-strain behavior of the constituent materials, concrete or reinforcing steel, of the cross section. Two models for stirrup-confined concrete and three models for FRP-confined concrete are used and evaluated to model the uniaxial stress-strain behavior of concrete. By using OpenSees cyclic static analyses of the force-based FFE are conducted to analytically simulate the cyclic tests of the pile specimens. The analytical results are compared with the experimental curves to validate the analytical models.

並列關鍵字

Wharf landing stage ； FRP ； PC pile ； finite element ； OpenSees ； lateral repeated loading analysis

參考文獻

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4. Caltrans(1986),“Bridge Design Specification”.

5. Crisfield, M.A., (1996) “Non-linear Finite Element Analysis of Solids and Structures”。