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  本文選題：鋼筋銹蝕 + 環(huán)向約束�。� 參考：《深圳大學》2017年碩士論文

【摘要】：鋼筋與混凝土間的可靠粘結是兩者共同工作的前提基礎,鋼筋銹蝕是鋼筋-混凝土界面粘結性能退化的主要原因。鋼筋銹蝕不僅引起自身截面的損失和力學性能的退化,且銹蝕產物的體積膨脹(往往為原來的2-4倍)將引起混凝土保護層開裂,因而破壞鋼筋-混凝土的界面粘結性能,嚴重地危害鋼筋混凝土結構的安全。鋼筋混凝土結構在銹蝕的同時往往承受著使用荷載且結構中存在約束,而約束應力和持荷作用的存在對鋼筋混凝土的銹脹和粘結必然有一定的影響,總的來說結構在諸多因素組合的復雜環(huán)境中經受著嚴峻的考驗。為了盡可能的模擬實際工程中結構所處環(huán)境,本文將研究環(huán)向約束、持荷作用、鋼筋銹蝕率以及相對保護層等參數對鋼筋混凝土銹脹和動力粘結的影響,主要內容包括以下工作:基于銹蝕產物體積協調和Fe元素守恒,考慮混凝土開裂的彈性回縮,建立了環(huán)向約束下試件表面裂縫寬度隨銹蝕率時變模型;通過XCT微觀試驗研究銹蝕率、環(huán)向約束、相對保護層等因素,如何影響模型參數銹蝕產物填充膨脹率n。通過鋼筋混凝土銹脹試驗系統(tǒng)的研究了各參數對銹脹的影響,并用試驗數據驗證了理論模型的合理性。對不同銹蝕率、環(huán)向約束、相對保護層、持載應力等參數耦合下的粘結試件進行了單向加載,結果表明:環(huán)向約束下試件的粘結性能,隨鋼筋銹蝕率的增加先增大后減小;環(huán)向約束剛度、持載應力等級、相對保護層等都對試件的粘結性能有提升。對銹蝕鋼筋混凝土粘結試件進行了變幅循環(huán)加載,并通過加載過程中粘結強度、粘結剛度以及耗能能力等指標評估了試件的粘結性能。研究發(fā)現:銹蝕率對于變幅循環(huán)粘結性能的影響也是先增大后減小;環(huán)向約束對于試件的變幅循環(huán)粘結性能有很大程度上的提升,尤其是施加了持載的銹蝕試件提升更加明顯;相對保護層對試件的變幅循環(huán)粘結性能也有一定程度的提升;持載應力的存在使得試件的變幅循環(huán)粘結性能得到了提升,但隨著持載應力比例的增大提升幅度逐漸降低。
[Abstract]:The reliable bond between steel bar and concrete is the premise of their joint work, and the corrosion of steel bar is the main reason for the degradation of bond performance between reinforcement and concrete interface. The corrosion of steel bars not only causes the loss of the section and the degradation of mechanical properties, but also the volume expansion of the corrosion products (usually 2-4 times of the original) will lead to the cracking of the concrete cover, thus destroying the interfacial bond property of the steel bar and concrete. Seriously endangering the safety of reinforced concrete structures. The reinforced concrete structure is often subjected to the use of the load and there are constraints in the structure while the corrosion of the reinforced concrete structure. However, the existence of the constraint stress and the holding load must have a certain impact on the corrosion expansion and bond of the reinforced concrete. In general, the structure is subjected to severe test in the complex environment of many factors combination. In order to simulate the environment of the structure in practical engineering as far as possible, this paper will study the influence of the parameters such as circumferential constraint, load retention, corrosion rate of steel bar and relative protective layer on the corrosion expansion and dynamic bond of reinforced concrete. The main contents are as follows: based on the volume coordination of corrosion products and the conservation of Fe element, considering the elastic shrinkage of concrete cracking, a time-varying model of surface crack width with corrosion rate under circumferential constraint is established. The effects of corrosion rate, circumferential constraint and relative protective layer on the filling expansion rate of corrosion products were studied by XCT microcosmic test. The influence of various parameters on the corrosion expansion of reinforced concrete was studied by means of the test system, and the rationality of the theoretical model was verified by the test data. Unidirectional loading of bonded specimens with different corrosion rates, circumferential constraints, relative protective layer, and load holding stress is carried out. The results show that the bond properties of the specimens under circumferential constraints first increase and then decrease with the increase of corrosion rate of steel bars. The bond properties of the specimens are improved by toroidal restraint stiffness, stress grade and relative protective layer. The cyclic loading of corroded reinforced concrete bonded specimens was carried out, and the bond properties of the specimens were evaluated by the bond strength, bond stiffness and energy dissipation capacity during the loading process. It is found that the effect of corrosion rate on cyclic bond properties of the specimens increases first and then decreases, and that the circumferential constraints improve the cyclic bond properties of the specimens to a great extent, especially for the specimens with holding load. The cyclic bond properties of the specimens were improved to a certain extent by the relative protective layer, and the cyclic bond properties of the specimens were improved by the existence of the holding stress, but gradually decreased with the increase of the ratio of the holding stress.
【學位授予單位】：深圳大學
【學位級別】：碩士
【學位授予年份】：2017
【分類號】：TU375

【參考文獻】

相關期刊論文 前10條

1 楊淑雁;劉西拉;;往復荷載下銹蝕鋼筋混凝土粘結滑移劣化模型[J];上海交通大學學報;2012年10期

2 鄧宗才;萬操;李建輝;;FRP加固對腐蝕鋼筋與混凝土黏結性能的影響[J];公路;2010年12期

3 張俊芝;王梁英;劉華挺;周建民;鄭輝;;人工氣候環(huán)境下荷載對鋼筋初銹時間的影響[J];武漢理工大學學報;2010年18期

4 滕海文;楊森茂;舒正昌;黃穎;;加載水平對雜散電流和鹽溶液共同作用下鋼筋銹蝕影響的模擬試驗研究[J];混凝土;2010年07期

5 王元戰(zhàn);田雙珠;王軍;那達慕;;不同環(huán)境條件下考慮荷載影響的氯離子擴散模型[J];水道港口;2010年02期

6 張偉平;崔瑋;顧祥林;王曉剛;;碳纖維布約束對銹蝕鋼筋與混凝土間粘結性能的影響[J];建筑結構學報;2009年05期

7 衛(wèi)軍;張華;徐港;王薇;黃瀅;王騰;;銹蝕鋼筋與混凝土粘結性能的試驗研究[J];鐵道科學與工程學報;2009年04期

8 曾嚴紅;顧祥林;張偉平;黃慶華;;混凝土中鋼筋加速銹蝕方法探討[J];結構工程師;2009年01期

9 高明贊;干偉忠;;瑞安市部分混凝土結構腐蝕破壞狀況調查與原因分析[J];溫州大學學報(自然科學版);2009年01期

10 王明斌;李術才;;雙向應力加載條件下鋼筋銹蝕致混凝土破壞應力分析[J];水利學報;2008年02期

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