- 摘 要
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(1 江西省交通科學研究院有限公司, 南昌 330200; 2 江西省橋梁結構重點實驗室, 南昌 330200;3 長大橋梁建設技術及裝備交通運輸行業(yè)研發(fā)中心, 南昌 330200)
摘要: 為了更好地評估單軌交通混凝土軌道梁加固后的服役壽命,建立了基于環(huán)境與疲勞荷載雙重作用影響下的加固梁抗彎承載力功能函數(shù)時變模型. 同時,基于 JC 法計算不同疲勞頻次下混凝土梁加固前后的時變抗彎可靠度. 結果表明:在疲勞與環(huán)境等因素作用下,早期混凝土梁的抗彎可靠度呈線性下降,而在后期降低速率進一步的增大,相比單一環(huán)境因素影響其可靠度下降更快. 另外,混凝土梁的抗彎可靠度呈現(xiàn)出隨年交變頻率增加而逐漸降低的明顯趨勢. 在運營基準期的 52%后,混凝土梁應用側面內(nèi)嵌 CFRP 加固技術,能夠繼續(xù)運營基準期的34%. 總的來看,采用側面內(nèi)嵌技術加固混凝土梁,可有效提供其服役壽命,服役早期加固效果更佳.
關鍵詞: 疲勞作用; 環(huán)境作用; 抗彎可靠度; 混凝土梁; 側面內(nèi)嵌技術; CFRP 加固
中圖分類號:TU375. 1 文獻標志碼:A 文章編號:1002-848X(2023)06-0143-07
DOI:10. 19701 / j. jzjg. 20201868
Reliability analysis on flexural resistance of concrete beams strengthened with CFRP considered action of fatigue
ZHU Zewen1,2,3, DAI Li1,2,3, MAO Lin1,2
(1 Jiangxi Transportation Research Institute Co. , Ltd. , Nanchang 330200, China; 2 Key Laboratory of BridgeStructure of Jiangxi Province, Nanchang 330200, China; 3 Research and Development Center on Technogies andEquipment of Long-span Bridge Construction Minsistry of Transport, Nanchang 330200, China)
Abstract: In order to better evaluate the service life of monorail rail strengthened concrete beams, a time-varying model ofthe functional function of the flexural capacity of the strengthened beams based on the dual effects of environment andfatigue was established. At the same time, the time-varying flexural reliability of concrete beams before and afterstrengthening under different fatigue frequencies was calculated based on the JC method. The results show that the flexuralreliability of concrete beams decreased linearly in the early stage with the service time, and the rate of decrease furtherincreases in the later stage, under the combined action of fatigue load and environment. Compared with a singleenvironmental factor, its reliability decreased faster. In addition, the flexural reliability of concrete beams show an obvioustrend of gradually decreasing as the frequency of annual alternating loads increases. The concrete beams were reinforcedwith side near surface mounted (SNSM) technique after 52% of the service base period, and could continue to serve about34% of the service base period. In general, the use of SNSM technique to strengthen the concrete beams can effectivelyprovide its service life, and the effect of early reinforcement is better.
Keywords:fatigue effect; environmental effect; flexural reliability; concrete beam; side near surface mounted technique;CFRP strengthening
∗江西省自然科學基金資助項目( 20202BABL214043),江西省交通運輸廳科技項目( 2019Z0002、2021C0008、2022H0014、2022C0007).
第一作者:朱澤文,博士,工程師,一級建造師,主要從事橋梁加固后力學性能及預防性養(yǎng)護技術研究,Email:001aasss002@163. com.
[引用本文] 朱澤文,代力,毛琳. 疲勞作用下 CFRP 加固混凝土梁抗彎可靠度分析[ J]. 建筑結構,2023,53(6):143-149. ZHU Zewen,DAI Li,MAO Lin. Reliability analysis flexural resistance of concrete beams strengthened with CFRPconsidered action of fatigue[J]. Building Structure,2023,53(6):143-149.
