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(1 河北工業(yè)大學(xué)土木工程學(xué)院，  天津 300401； 2 河北省土木工程技術(shù)研究中心， 天津 300401)

［摘要］為了得到重載交通對(duì)預(yù)應(yīng)力混凝土梁的疲勞性能影響，對(duì)9根預(yù)應(yīng)力混凝土模型梁分別進(jìn)行靜載試驗(yàn)和等幅疲勞試驗(yàn)研究。研究結(jié)果表明，部分試驗(yàn)梁在經(jīng)歷過200萬次疲勞荷載作用后，其靜力極限強(qiáng)度不但沒有大幅度降低，反而略有提高；在重載作用下的疲勞破壞均始于非預(yù)應(yīng)力鋼筋的疲勞斷裂；試驗(yàn)過程中疲勞損傷明顯呈三階段發(fā)展規(guī)律，當(dāng)疲勞荷載上限達(dá)到0-7倍的極限荷載時(shí)，疲勞壽命大于200萬次，當(dāng)疲勞荷載上限達(dá)到0-75倍極限荷載時(shí)，疲勞壽命僅為10-2萬次，當(dāng)疲勞荷載上限達(dá)到0-85倍的極限荷載時(shí)，預(yù)應(yīng)力混凝土梁的疲勞壽命僅為5-1萬次；得到了預(yù)應(yīng)力混凝土梁的容許疲勞壽命方程。

［關(guān)鍵詞］重載交通； 疲勞壽命； 等幅疲勞試驗(yàn)； 預(yù)應(yīng)力混凝土梁； 疲勞損傷

中圖分類號(hào)：TU375文獻(xiàn)標(biāo)識(shí)碼：A文章編號(hào)：1002-848X(2017)06-0055-05

Study of heavy load traffic effect on fatigue performance of pre-stressed concrete beams

Zhao Chuan1,2, Dou Yuanming1,2, Sun Jishu1,2, Li Yanfeng1,2

(1 College of Civil Engineering, Hebei University of Technology, Tianjin 300401, China;

2 Civil Engineering Technology Research Center of Hebei Province, Tianjin 300401,China)

Abstract:In order to get the impact of heavy load traffic on fatigue performance of pre-stressed concrete beams, static load tests and constant amplitude fatigue experiments were conducted on 9 pre-stressed concrete beam models respectively. The results show that static ultimate strength of part of the experimental beams not only fails to reduce significantly but slightly increases after experiencing 2 million times of fatigue load actions. The fatigue damage under heavy load starts from fatigue fracture of non-pre-stressed reinforcement. The fatigue damage during the test shows three-stage development rule clearly. When the upper limit of fatigue load reaches the 0-7 times of the ultimate load, the fatigue life is over 2 million times. When the upper limit of fatigue load reaches the 0-75 times of the ultimate load, the fatigue life is only 102 000 times. When the upper limit of fatigue load reaches the 0-85 times of the ultimate load, the fatigue life is only 51 000 times. Then the allowed fatigue life equation of pre-stressed concrete beam was obtained.

Keywords:heavy load traffic; fatigue life; constant amplitude fatigue experiment; pre-stressed concrete beam; fatigue damage

*河北省交通廳資助項(xiàng)目（Y-2012046）。

作者簡(jiǎn)介：趙川，博士，Email: zcsunshine@yeah.net。