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曾慶響^1,2，韓大建¹
(1 華南理工大學(xué)亞熱帶建筑科學(xué)國家重點(diǎn)實(shí)驗(yàn)室，廣州510640; 2五邑大學(xué)土木建筑學(xué)院，江門529020)

[摘要] 預(yù)應(yīng)力混凝土梁橋因具有良好的受力性能而在橋梁工程中得到廣泛應(yīng)用?；炷翗蛄旱拈_裂和撓度過大已經(jīng)逐步成為普遍現(xiàn)象，橋梁結(jié)構(gòu)的加固改造已經(jīng)成為學(xué)術(shù)研究和工程應(yīng)用的熱點(diǎn)。介紹了橋梁加固設(shè)計(jì)的基本原則。將橋梁結(jié)構(gòu)的加固方法劃分為主動加固法和被動加固法兩大類。分析了截面增大加固法、粘貼鋼板和纖維復(fù)合材料加固法、體外預(yù)應(yīng)力加固法和改變結(jié)構(gòu)體系加固法等的特點(diǎn)與適用范圍。總結(jié)了橋梁工程中裂縫處理的常用方法和常用加固材料的力學(xué)性能。指出了橋梁工程加崮中應(yīng)注意的主要問題。
[關(guān)鍵詞] 混凝土橋梁；加固；體外預(yù)應(yīng)力；裂縫；纖維復(fù)合材料

Strengthening and crack treatments for prestressed concrete girder bridges
Zeng Qingxiang^1,2, Han Dajian¹
(1 State Key Laboratory of Subtropical Building Science, South China University of Technology, Guangzhou 510640, China; 2 School of Civil Engineering & Architecture, Wuyi University, Jiangmen 529020, China)

Abstract: Prestressed concrete box girder  (PC bridges)  is widely applied in bridge engineering for its favorable mechanical performance. Cracking and over-deformation have been beconung the common phenomenon for PC bridges. The problem of structural strengthening for concrete girder bridges is universally concerned in the field of academic research and engineering application in bridge structure engineering. The structural strengthening methods in PC girder are classified into two categories, active strengthening method and passive strengthening method. The features and application scope of some structural strengthening methods, such as structure member strengthening with RC & PC, structure member strengthening with bonded steel plate or fiber reinforced polymer, structure member strengthening with external prestressing, strengthening by changing structure system and so on, are analyzed for PC bridges. Finally, some treatment method of cracks and mechanical properties index of strengthening materials for PC bridges are summarized briefly. Some main problems should be paid attention in structure strengthening are pointed out for the benefit of further strengthening design for PC bridges.
Keywords: prestressed concrete bridge; strengthening; external prestressing; crack; fiber reinforced polymer( FRP)