【正文】 s anticipating the crack that reaction crack and reinforcing bar rust eclipse cause is the most familiar in the reinforced concrete structure of because of chemical reaction but cause of crack. The concrete blend a future reunion creation some alkalescence ion, these ion with some activity the bone anticipate creation chemical reaction and absorb surroundings environment in of water but the physical volume enlarge, make concrete crisp loose, inflation open crack. In this kind of crack general emergence concrete structure usage period, once appear very difficult remediable, so should at under construction adopt valid the measure carry on prevention. Main of prevention measure: While being to choose to anticipate with the alkali activity small freestone bone. Two is the in addition which choose to use low lye mire with low alkali or have no alkali. Three is the Chan which choose to use acmodation with anticipate to repress an alkali bone to anticipate reaction. Because the concrete sprinkle to build, flap Dao bad perhaps is a reinforcing bar protection layer thinner, the harmful material get into concrete to make reinforcing bar creation rust eclipse, the reinforcing bar physical volume of the rust eclipse inflation, cause concrete bulge crack, the crack of this kind type much is a crack lengthways, follow the position of reinforcing bar of prevent measure from have:One is assurance reinforcing bar protection the thickness of the is a concrete class to go together with to want is a concrete to sprinkle to note and flap Dao airtight is a reinforcing bar surface layer Tu2 Shua antisepsis coating. 3 Crack processing 浙江大學城市學院畢業(yè)設計 外文翻譯 The emergence of the crack not only would influence structure of whole with just degree, return will cause the rust eclipse of reinforcing bar, acceleration concrete of carbonization, lower durable and anti of concrete tired, anti Shen according to the property of crack and concrete circumstance we want differentiation to treat, in time processing, with assurance building of safety usage. The repair measure of the concrete crack is main to have the following some method:Surface repair method, infuse syrup, the Qian sew method, the structure reinforce a method, concrete displacement method, electricity chemistry protection method and imitate to living from heal method. Surface repair the method be a kind of simple, familiar of repair method, it main be applicable to stability and to structure loading the ability don39。t resist its constringency, therefore creation influence concrete Su constringency open the main factor of crack to have water ash ratio, concrete of condense time, environment temperature, wind velocity, relative humidity...etc.. Main prevention measure:One is choose to use stem the Suo value smaller higher Huo sour salt of the earlier period strength or mon the Huo sour brine is strict the control water ash ratio, the Chan add to efficiently reduce water to increment the collapse of concrete fall a degree and with easy, decrease cement and water of is to sprinkle before building concrete, water basic level and template even to soak is in time to overlay the perhaps damp grass mat of the plastics thin film, hemp slice etc., keep concrete eventually before the Ning surface is moist, perhaps spray to protect etc. to carry on protect in the concrete is in the heat and strong wind the weather to want to establish to hide sun and block breeze facilities, protect in time. Sink to sink crack and prevention The creation which sink to sink crack is because of the structure foundation soil quality not and evenly, loose soft or return to fill soil dishonest or soak in water but result in the asymmetry sink to decline with the result that。s life and property safety. A lot of all of crash of engineerings is because of the unsteady development of the crack with the result that. Modern age science research with a great deal of of the concrete engineering practice certificate, in the concrete engineering crack problem is ineluctable, also acceptable in certainly of the scope just need to adopt valid of measure will it endanger degree control at certain of scope reinforced concrete norm is also explicit provision:Some structure at place of dissimilarity under the condition allow existence certain the crack of at under construction should as far as possible adopt a valid measure control crack creation, make the structure don39。二是選用低堿水泥和低堿或無堿的外加劑。十二是減小約束，澆筑混凝土前宜在基巖和老混凝土上鋪設 5mm 左右的砂墊層或使用瀝青等材料涂刷。四是改善骨料級配，摻加粉煤灰或高效減水劑等來減少水泥用量，降低水化熱。在混凝土的施工中當溫差變化較大，或者是混凝土受到寒潮的襲擊等，會導致混凝土表面溫度急劇下降，而產(chǎn)生收縮，表面收縮的混凝土受內(nèi)部混凝土的約束，將產(chǎn)生很大的拉應力而產(chǎn)生裂縫，這種裂縫通常只在混凝土表面較淺的 范圍內(nèi)產(chǎn)生。二是保證模板有足夠的強度和剛度，且支撐牢固，并使地基受力均勻。五是在高溫和大風天氣要設置遮陽和擋風設施， 并 及時 進行 養(yǎng)護。 塑性收縮裂縫及預防 塑性收縮是指混凝土在凝 結之前，表面因水分蒸發(fā) 較快而產(chǎn)生的收縮。干縮裂縫 的存在 通常會影響混凝土的抗?jié)B 透 性 能 ，引起鋼筋的銹蝕 ， 影響混凝土的耐久性，在水壓力的作用下會產(chǎn)生水力劈裂 ， 影響混凝土的承載力 性能 等等。但在施工中應盡量采取有效措施控制裂縫產(chǎn)生，使結構盡可能不出現(xiàn)裂縫或盡量減少裂縫的數(shù)量和寬度，尤其要盡量 避免有害裂縫的出現(xiàn)，以 確保工程質量。 關鍵詞： 混凝土 ， 裂縫 ， 預防 ， 處理 前言 混凝土是一種由砂石骨料、水泥、水及其 他多種材料混合而形成的脆性材料。很多工程的出 事都是由于裂縫的不穩(wěn)定發(fā)展所致。干縮裂縫的產(chǎn)生主要是由于混凝土內(nèi)外 層混凝土水分蒸發(fā)程度不同而導致的變形不同 ：混凝土受外部條件的影響，表面水分 蒸發(fā) 過 快，變形較大，內(nèi)部 水分蒸發(fā)滿 濕度變化較小變形較小，較大的表面干縮變形受到混凝土內(nèi)部 較小 約束， 因 產(chǎn)生較大拉應力而 連帶產(chǎn)生裂縫。四是加強混凝土的早期養(yǎng)護 時長 ，并適當延長混凝土的養(yǎng)護時間。二是嚴格控制水灰比，摻入高效減水劑來增加混凝土的坍落度與 和易性，減少水泥及浙江大學城市學院畢業(yè)設計