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外文文獻(xiàn)翻譯工程管理專業(yè)建筑施工混凝土裂縫的預(yù)防與處理中英文對照(完整版)

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【正文】 te of inside outside difference in is the supervision which strengthen concrete temperature, adopt to cool off in time, protection is to reserve temperature constringency to is to let up to control, sprinkle proper before building concrete in the Ji rock and old concrete top build a 5 mm or so sand mat a layer or usage asphalt etc. material Tu2 is to strengthen concrete to protect, the concrete after sprinkle build use moist grass Lian in time, hemp slice39。t big in match ratio design give settle of use water quantity. Four is the earlier period which strengthen concrete to protect, and appropriate extension protect of concrete time. Winter construction want to be appropriate extension concrete heat preservation to overlay time, and Tu2 Shua protect to protect. Five is a constitution the acmodation is in the concrete structure of the constringency sew. The Su constringency crack and prevention Su constringency is the concrete is before condense, surface because of lose water quicker but creation of constringency. The Su constringency crack is general at dry heat or strong wind the weather appear, crack39。 4 結(jié) 論 裂縫是混凝土結(jié)構(gòu)中普遍存在的一種現(xiàn)象,它的出現(xiàn)不僅會降低建筑物的抗?jié)B能力,影響建筑物的使用功能,而且會引起鋼筋的銹蝕,混凝土的碳化,降低材料的耐久性,影響建筑物的承載能力,因此要對混凝土裂縫進(jìn)行認(rèn)真研究、區(qū)別對待,采用合理的方法進(jìn)行處理,并在施工中采取各種有效的預(yù)防措施來預(yù)防裂縫的出現(xiàn)和發(fā)展,保證建筑物和構(gòu)件的安全。 結(jié)構(gòu)加固法 當(dāng)裂縫影響到混凝土結(jié)構(gòu)的性能時(shí),就要考慮采取加固法對混凝土結(jié)構(gòu)進(jìn)行處理。因此根據(jù)裂縫的性質(zhì)和 2021級工程管理專業(yè)英語科技文獻(xiàn)翻譯 5 具體情況我們要區(qū)別對待、及時(shí)處理,以保證建筑物的安全使用。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(shè) 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(dāng)溫差變化較大,或者是混凝土受到寒潮的襲擊等,會導(dǎo)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(yīng)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(qiáng)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(fēng)天氣要設(shè)置遮陽和擋風(fēng)設(shè)施,及時(shí)養(yǎng)護(hù)。 塑性收縮裂縫及預(yù)防 塑性收縮是指混凝土在凝結(jié)之前,表面因失水較快而產(chǎn)生的收縮。干縮裂縫通常會影響混凝土的抗?jié)B性,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等等。但在施工中應(yīng)盡量采取有效措施控制裂縫產(chǎn)生,使結(jié)構(gòu)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),從而確保工程質(zhì)量。 關(guān)鍵詞 : 混凝土 裂縫 預(yù)防 處理 1 引言 混凝土是一種由砂石骨料、水泥、水及其他外加材料混合而形成的非均質(zhì)脆性材料。很多工程的失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)外水分蒸發(fā)程度不同而導(dǎo)致變形不同的結(jié)果:混凝土受 2021級工程管理專業(yè)英語科技文獻(xiàn)翻譯 2 外部條件的影響,表面水分損失過快,變形較大,內(nèi)部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)部約束,產(chǎn)生較大拉應(yīng)力而產(chǎn)生裂縫。四是加強(qiáng)混凝土的早期養(yǎng)護(hù),并適當(dāng)延長混凝土的養(yǎng)護(hù)時(shí)間。二是嚴(yán)格控制水灰比,摻加高效減水劑來增加混凝土的坍落度和和易性,減少水泥及水的用量。裂縫寬度受溫度變化的影響較小。混凝 土澆筑后,在硬化過程中,水泥水化產(chǎn)生大量的水化熱,(當(dāng)水泥用量在350550 kg/m3,每立方米混凝土將釋放出 1750027500kJ的熱量,從而使混凝土內(nèi)部溫度升達(dá) 70℃左右甚至更高)。 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。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。 混凝土拌和后會產(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)并吸收周圍環(huán)境中的水而體積增大,造成混凝土酥松、膨脹開裂。三是混凝土澆注要振搗密實(shí)。常用的膠結(jié)材料有水泥漿、環(huán)氧樹脂、甲基丙烯酸酯、聚氨酯等化學(xué)材料。陰極防護(hù)法、氯鹽提取法、堿性復(fù)原法是化學(xué)防護(hù)法中常用而有效的三種方法。Protected environment not appropriate the crack etc. caused with chemical differentiation to treat in the actual engineering, work176。 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 sprinkle infusing the foundation in the process is soak by is time that template tore down to can39。s withdrawing a method, alkalescence to recover a method is a chemistry protection method in three kinds of in mon use but valid advantage of this kind of method is a protection method under the influence of environment factor smaller, apply reinforcing bar, concrete of longterm antisepsis, since can used for crack structure already can also used for new set up structure. Imitate to living from legal more Imitate to living from heal the method be a kind of new crack treatment, its mimicry living creature anization secrete a certain material towards suffering wound part auto, but make the wound part heal of function, join some and special position(such as contain to glue knot of the liquid Xin fiber or capsule) in the concrete of the tradition the position, at concrete inner part formation the intelligence type imitate to living from heal nerve work system, be the concrete appear crack secrete a parts of liquid Xin fiber can make the crack re heal. 4 Conclusion The crack is widespread in the concrete structure existence of a kind of phenomenon, it of emergence not only will lower the anti Shen of building ability, influence building of usage function, and will cause the rust eclipse of reinforcing bar, the carbonization of concrete, lower the durable of material, influence building of loading ability, so want to carry on to the concrete crack earnest research, differentiation treat, adoption reasonable of the method carry on processing, and at under construction adopt various valid of prevention measure to prevention。The size bigger structure of the beam plank length, the crack run parallel with short side more。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
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