【正文】 內(nèi)部溫度急劇上升，而混凝土表面散熱較快，這樣就形成內(nèi)外的較大溫差，較大的溫差造成內(nèi)部與外部熱脹冷縮的程度不同，使混凝土表面產(chǎn)生一定的拉應(yīng)力。四是模板拆除的時(shí)間不能太早，且要注意拆模的先后次序。地基變形穩(wěn)定之后，沉陷裂縫也基本趨于穩(wěn)定。此類裂縫多為深進(jìn)或貫穿性裂縫，其走向與沉陷情況有關(guān)，一般沿與地面垂直或呈 30176。三是澆筑混凝土之前，將基層和模板澆水均勻 直至 濕透。較短的裂縫一般長 2030cm，較長的裂縫可 以 達(dá) 到 23m，寬 15mm.其產(chǎn)生的主要原因是 ：混凝土在終凝前幾乎沒有強(qiáng)度或強(qiáng)度很小，或者混 凝土剛剛終凝而強(qiáng)度很小時(shí)，受高溫或較大風(fēng)力的影響，混凝土表面水分蒸發(fā) 過快，造成 混凝土毛細(xì)管中產(chǎn)生較大的負(fù)壓 力從 而使混凝土體積急劇收縮，而此時(shí)混凝土的強(qiáng)度又無法抵抗其本身收縮，因 此產(chǎn)生龜裂。冬季施工時(shí)要適當(dāng)延長混凝土 的保溫覆蓋時(shí)間，并涂刷保護(hù)劑保 護(hù)。 主要預(yù)防措施：一是選用收縮量較小的水泥，一般 多采用中低熱水泥和粉煤灰水泥，降低水泥的用量。相對(duì) 濕度越低，水泥漿體干縮越大，干縮裂縫越易產(chǎn)生。在實(shí)際工程中 應(yīng) 區(qū)別對(duì)待，根據(jù)實(shí)際情況解決 實(shí)際 問題。近代科學(xué)研究和大量的混凝土工程實(shí)踐證明，在混凝 土工程中裂縫問題是不可避免的，在一定的范圍內(nèi)也是可以接受的，但 要采取有效的措施將其危害程度控制在一定的范圍之內(nèi)。微裂縫通常是一種無害裂縫，對(duì)混凝土的承重、 抗?jié)B透 及其他一些使用功能不產(chǎn)生危害。 畢業(yè)設(shè)計(jì)（論文） 譯文及原稿 譯文題目 建筑混凝土裂縫的預(yù)防和處理 原稿題目 Building construction concrete crack of prevention and processing 原稿出處 Dimosi M， CANADIAN JOURNAL OF CIVIL ENGINEERING， [M]， Canadian： The Canadian civil engineering press， 2020. 浙江大學(xué)城市學(xué)院畢業(yè)設(shè)計(jì) 外文翻譯 建筑混凝土裂縫的預(yù)防與處理 摘 要： 混凝土的裂縫問題是一個(gè)普遍存在而又難以解決的工程實(shí)際問題，本文將對(duì)混凝土工程中熟悉的裂縫問題進(jìn)行研究分析，并針對(duì)具體情況提出一些預(yù)防與處理措施。但是在混凝土受到荷載、溫差等 多重效應(yīng) 作用之后，微裂縫就會(huì)不斷的擴(kuò)展和連通，最終形成我們 日常 肉眼可見的宏觀裂縫，也就是混凝土工程中常說的裂縫。鋼筋混凝土規(guī)范 明文規(guī)定：不同結(jié)構(gòu)在不同的所處條件下 ，允許存在一定寬度的裂縫。 混凝土工程中常見裂縫及預(yù)防 干縮裂縫及預(yù)防 浙江大學(xué)城市學(xué)院畢業(yè)設(shè)計(jì) 外文翻譯 干縮裂縫 通常 出現(xiàn)在混凝土養(yǎng)護(hù)結(jié)束后的一段時(shí)間或是混凝土澆筑完 畢后的一周左右。干縮裂縫多為表面的平行線狀或網(wǎng)狀淺細(xì)裂縫，寬度一般 在 之間， 在 大體積混凝土中 的 平面部位 比較 多見，較薄的梁板中多沿其短向分布 裂紋 。 二是混凝土的干縮受水灰比的影響較大，水灰比越大，干縮 也就 越大 ，因此在混凝土配合比設(shè)計(jì)中應(yīng)盡量控制好水灰比的選用，同時(shí)摻加適量的減水劑。五是在混凝土結(jié)構(gòu)中設(shè)置合適 的收縮縫。影響混凝土塑性收縮開裂的主要因素有水灰比、混凝土的凝結(jié)時(shí)間、環(huán)境溫度、風(fēng)速、相對(duì)濕度等等。四是及時(shí)覆蓋塑料薄膜或者潮濕的草墊、麻片等，保持混凝土終凝前表面濕潤，或者在混凝土表面噴灑養(yǎng)護(hù)劑等進(jìn)行養(yǎng)護(hù)。 45176。 主要預(yù)防措施：一是對(duì)松軟土、回填土地基在上部結(jié)構(gòu)施工前應(yīng)進(jìn)行必 要的夯實(shí)和加固。五是在凍土上搭設(shè)模板時(shí)要注意采取一定的預(yù)防措施。當(dāng)拉應(yīng)力超過混凝土的抗拉強(qiáng)度極限時(shí)，混凝土表面就會(huì)產(chǎn)生裂縫，這種裂縫多發(fā)生在混凝土施工中后期。高溫膨脹引起的混凝土溫度裂縫是通常中間粗兩端細(xì)，而冷縮裂縫的粗細(xì)變化不太明顯。三是降低水灰比，一般混凝土的水灰比控制在 以下。七是高溫季節(jié)澆筑時(shí)可以采用搭設(shè)遮陽板等輔助措施控制混凝土的溫升，降低澆筑混凝土的溫度。十一是預(yù)留溫度收縮縫。十四是混凝土中配置少量的鋼筋或者摻入 纖維材料將混凝土的溫度裂縫控制在一定的范圍之內(nèi)。主要的預(yù)防措施：一是選用堿活性小的砂石骨料。通常的預(yù)防措施有：一是保證鋼筋保護(hù)層的厚度。 浙江大學(xué)城市學(xué)院畢業(yè)設(shè)計(jì) 外文翻譯 Building constructing concrete crack of prevention and processing Abstract： The crack problem of concrete is a widespread existence but again difficult in solve of engineering actual problem, this text carried on a study analysis to a little bit familiar crack problem in the concrete engineering, and aim at concrete the circumstance put forward some prevention, processing measure. Key word: Concrete crack prevention processing 1 Foreword Concretes is a kind of anticipate by the freestone bone, cement, water and other mixture but formation of the in addition material of quality brittleness not and all material. Because the concrete construction transform with oneself, control etc. a series problem, harden model of in the concrete existence numerous tiny hole, spirit cave and tiny crack, is exactly because these beginning start blemish of existence just make the concrete present one some not and all the characteristic of quality. The tiny crack is a kind of harmless crack and accept concrete heavy, defend Shen and a little bit other use function not a creation to endanger. But after the concrete be subjected to lotus carry, difference in temperature etc. function, tiny crack would continuously of expand with connect, end formation we can see without the aid of instruments of macro view the crack be also the crack that the concrete often say in the engineering. Concrete building and Gou piece usually all take sewer to make of, because of crack of existence and development usually make inner part of reinforcing bar etc. material creation decay, lower reinforced concrete material of loading ability, durable and anti Shen ability, influence building of external appearance, service life, severity will threat arrive people39。Protected environment not appropriate the crack etc. caused with chemical differentiation to treat in the actual engineering, work176。s much presenting in the center breadth, both ends be in the centerthin and the length be different, with each other not coherent crack general long 2030 cm, the longer crack can reach to a 23 m, breadth 15 creation of main reason is:The concrete is eventually almost having no strength or strength before the Ning very small, perhaps concrete just eventually Ning but strength very hour, be subjected to heat or pare strong wind dint of influence, the concrete surface lose water to lead quick, result in in the capillary creation bigger negative press but make a concrete physical volume sharply constringency, but at this time the strength of concrete again can39。 Cape direction development, bigger sink to sink crack, usually have certain of wrong, crack width usually with sink to decline quantity direct proportion width under the influence of temperature variety foundation after transform stability sink to sink crack also basic tend in stability. Main prevention measure:One is rightness loose soft soil, return to fill soil foundation a construction at the upper part structure front should carry on necessity of Hang solid with is the strength that assurance template is enough and just degree, and prop up firm, and make the foundation be subjected to dint is keep concrete from