【正文】 he 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。t Suo crack of the creation be main is because of concrete inside outside humidity evaporate degree dissimilarity but cause to transform dissimilarity of result:The concrete is subjected to exterior condition of influence, surface humidity loss lead quick, transform bigger, inner part degree of humidity variety smaller transform smaller, bigger surface stem the Suo transform to be subjected to concrete inner part control, creation more big pull should dint but creation relative humidity is more low, cement syrup body stem Suo more big, stem the Suo crack be more easy the Suo crack is much surface parallel lines form or the shallow thin crack, width many between mm, the flat surface part much see in the big physical volume concrete and follow it more in thinner beam plank short to Suo crack usually the anti Shen of influence concrete, cause the durable of the rust eclipse influence concrete of reinforcing bar, under the function of the water pressure dint would creation the water power split crack influence concrete of loading dint etc..Concrete stem the Suo be main with water ash of the concrete ratio, the dosage of the position, cement of cement, gather to anticipate of the dosage of the property and dosage, in addition etc. relevant. Main prevention measure: While being to choose to use the constringency quantity smaller cement, general low hot water mire and powder ash from stove cement in the adoption, lower the dosage of cement. Two is a concrete of stem the Suo be subjected to water ash ratio of influence more big, water ash ratio more big, stem Suo more big, so in the concrete match the ratio the design should as far as possible control good water ash ratio of choose to use, the Chan add in the meantime acmodation of reduce water. Three is strict 浙江大學(xué)城市學(xué)院畢業(yè)設(shè)計(jì) 外文翻譯 control concrete mix blend with under construction of match ratio, use of concrete water quantity absolute can39。Protected environment not appropriate the crack etc. caused with chemical differentiation to treat in the actual engineering, work176。t appear crack possibly or as 浙江大學(xué)城市學(xué)院畢業(yè)設(shè)計(jì) 外文翻譯 far as possible decrease crack of amount and width, particularly want to as far as possible avoid harmful crack of emergence, insure engineering quality thus. Concrete crack creation of the reason be a lot of and have already transformed to cause of crack:Such as temperature variety, constringency, inflation, the asymmetry sink to sink etc. reason cause of crack。 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。三是混凝土澆注要振搗密實(shí)。通常的預(yù)防措施有：一是保證鋼筋保護(hù)層的厚度。三是選用合適的摻和料抑制堿骨料反應(yīng)。主要的預(yù)防措施：一是選用堿活性小的砂石骨料。 混凝土拌和后會(huì)產(chǎn)生一些堿性離子，這些離子與某些活性骨料產(chǎn)生化學(xué)反應(yīng)并吸收周?chē)h(huán)境中的水而體積增大，造成混凝土酥松、膨脹開(kāi)裂。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)。十三是加強(qiáng)混凝土養(yǎng)護(hù)，混凝土澆筑后，及時(shí)用濕潤(rùn)的草簾、麻片等覆蓋，并注意灑水養(yǎng)護(hù)，適當(dāng)延長(zhǎng)養(yǎng)護(hù)時(shí)間，保證混凝土表面緩慢冷卻。十一是預(yù)留溫度收縮縫。九是在大體積混凝土內(nèi)部設(shè)置冷卻管道，通冷水或者冷氣冷卻，減小混凝土的內(nèi)外溫差。七是高溫季節(jié)澆筑時(shí)可以采用搭設(shè)遮陽(yáng)板等輔助措施控制混凝土的溫升，降低澆筑混凝土的溫度。五是改善混凝土的攪拌加工工藝，降低混凝土的澆筑溫度。三是降低水灰比，一般混凝土的水灰比控制在 以下。 主要預(yù)防措施：一是盡量選用低熱或中熱水泥，如礦渣水泥、粉煤灰水泥等。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。 溫度裂縫的走向通常無(wú)一定規(guī)律，大面積結(jié)構(gòu)裂縫?？v橫交錯(cuò)；梁板類(lèi)長(zhǎng)度尺寸浙江大學(xué)城市學(xué)院畢業(yè)設(shè)計(jì) 外文翻譯 較大的結(jié)構(gòu)，裂縫多平行于短邊；深入和貫穿性的溫度裂縫一般與短邊方向平行或接近平行，裂縫沿著長(zhǎng)邊分段出現(xiàn)，中間較密。當(dāng)拉應(yīng)力超過(guò)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?；炷翝仓?以 后，在硬化 的 過(guò)程中，水泥水化 所 產(chǎn)生大量的水化熱，（當(dāng)水泥用量在