預(yù)應(yīng)力混凝土的廣泛應(yīng)用外文翻譯

1、<p>　　西 南 交 通 大 學(xué)</p><p><b>　　本科畢業(yè)設(shè)計</b></p><p><b>　　外文資料翻譯</b></p><p>　　年 級:2006級</p><p>　　學(xué) 號:20060058</p><p>　　姓 名

2、:郭 鵬</p><p>　　專 業(yè):土木工程</p><p><b>　　指導(dǎo)老師:楊榮山</b></p><p>　　2010年 6 月</p><p><b>　　英文翻譯原稿</b></p><p>　　Prestressed Concrete&

3、#160;the extensive application </p><p>　　Priestesses concrete is used in concrete structures under load before the production phase, the use of pre-stage of the tension zone imposed stress, the

4、stress caused by an artificial state. When the components used to bear a load and stress, first of all to offset the pre-stress concrete, and then as the load increases, the Rajah area of concrete produced stress. Theref

5、ore, concrete cracks may delay the emergence and implementation, to meet the application requirements. In structural members to</p><p>　　China's use of priestesses concrete sleeper more than 30 years, th

6、e concrete sleeper in a lot of damage related to traffic safety, which is often considered failures sleeper operation should be replaced on the line. But to put the new sleeper, in addition to re-create, but also handlin

7、g, transport and went to the line on the pillow-for-work, not only need to spend a lot of manpower and material resources, and sometimes impact on traffic, the cost is often a sleeper itself Cost Four to five times</p

8、><p>　　Sleeper as a priestess’s concrete structure, cracks are difficult to avoid, priestesses concrete sleeper on the causes and dangers of cracks on how the prevention and control of cracks, concrete sleeper

9、to improve the durability of the structure, to extend the life of sleeper, Will be very important.</p><p>　　1. causes cracks in concrete sleeper</p><p>　　Cracks in concrete sleeper can be genera

10、ted from the structure, processes, materials and other aspects of, or from the design, manufacture, laying, use of research. Here, only physical, chemical, mechanical point of view for analysis.</p><p>　　1.1

11、   mechanical factors</p><p>　　Concrete sleeper suffered moment not only the size and Zhen hang dynamic pressure, but also with the sub occipital Ballast support of the state. The laying of the ori

12、ginal design requirements and conservation should be the middle part of the sleeper emptied 400 ram, hollowed out part of Ballast top of the pillow at the end should be less than 30 mm, to avoid negative moment too large

13、 a pillow in the upper horizontal cleft. In recent years do not require the middle emptied, the middle should be f</p><p>　　1.2   physical factors</p><p>　　Physical factors means the s

14、leeper manufacture and laying, in the course of operating the hot and cold, wet and dry, such as the role of freezing and thawing. When the conservation process of warming up steam soon, when the high temperature thermos

15、tat, the concrete gas, water, cement, gravel, and so different coefficient of thermal expansion of different materials, and concrete structure of the early intensity and low, so that high-temperature gas, water greatly e

16、xpanded, resulting in Concrete i</p><p>　　For some time, many factories in the production of steam conservation sleeper no pre-custody time, warming up quickly, thermostat temperature is higher than 95 ℃, St

17、ripping at the end of the concrete sleeper swelling, loose situation often occurred.</p><p>　　1.3 Chemical factors</p><p>　　Chemical factors that steel corrosion, concrete corrosion, carbonated,

18、 alkali aggregate reaction, and so on. China on the concrete sleeper, which alkali aggregate reaction (AAR) caused the damage can not be ignored. Alkali aggregate reaction of the three conditions are: aggregate activity,

19、 high-alkali cement and water, the destruction of more than three is a chemical reaction, in the aggregate in the concrete and cement interface on the formation of silicate gel, Volume expansion caused concrete</p>

20、<p>　　As China's cement production for a long time not to limit alkali content. Using high-alkali cement increased cement production and reduce costs. China has some areas of concrete coarse aggregate (stone)

21、has obvious base activity, a combination of both together, easy to form alkali aggregate reaction (AAR) damage. This issue is from the late 1960s, a factory production of priestess’s concrete sleeper (and bridges) and th

22、e fracture occurred repeatedly cracking, and the structure, process, laying t</p><p>　　To sum up, vertical cracks in the main by internal factors (materials, structure, technology factors) due to external fa

23、ctors (loading and freeze-thaw, wet and dry cycle) is only promote their development, horizontal cracks are internal (priestesses reinforced, section And concrete strength) and external factors (loading and sleeper bound

24、ary conditions) caused by a combination.</p><p>　　來源：(http://blog.sina.com.cn/s/blog_4e5c779201009atn.html) - Prestressed Concrete the extensive application o_軒轅靈兒_新浪2. cracks in the

25、 concrete sleeper durability of the structure</p><p>　　(1) sleeper in the open-air environment, because of dense concrete, water, gas will not infiltrate into the internal, but cracks in to a certain width a

26、nd depth of cracks at the protection layer, water, gas will reach the penetration along the cracks gradually reinforced , Caused steel corrosion and rust, rust is a compound of iron (iron oxide), four times its volume ex

27、pansion in the concrete caused internal stress, leading to further cracking concrete, reinforced and priestesses concrete and Bo</p><p>　　(2) Study shows that only cracks in the concrete structure of a certa

28、in width, water, gas can be infiltrated, from steel corrosion. Domestic and international norms, reinforced concrete structure to allow the crack width of 0.1 ~ 0.3mm (depending on the media environment), priestesses con

29、crete structure does not allow even a crack, its purpose is to ensure that no reinforcement corrosion. However, many times at home and abroad for the investigation and trial, and that crack width and not directl</p>

30、;<p>　　(3) Research also shows that the vertical cracks on the durability of the general structure than the horizontal cracks serious. Reinforced concrete structures due to the longitudinal cracks will cause the s

31、teel corrosion protection layer peeling off; cracking concrete expansion will cause osteoporosis, swap block. The author had been taken from different routes 16, with a different state of the sleeper Split 11, the normal

32、 sleeper 5, case-by-track roots are cracking under section static strength</p><p>　　3. concrete sleeper cracks in the prevention and control</p><p>　　Sleeper as a priestess’s concrete structure,

33、 in order to completely eliminate cracks is very difficult to do. After all, but the crack is harmful. For this reason, every effort should be made to prevent the emergence of crack.</p><p>　　Prevention and

34、control of cracks, you can start with a three-pronged:</p><p>　　First, from the mechanical point of view, in order to prevent horizontal cracks, except in accordance with the greatest possible load, the rati

35、onal allocation of priestesses reinforced, we must also strengthen the end of the stirrups and the spiral reinforcement clip bolt whole configuration. In addition, to strengthen the conservation line maintenance so that

36、the sleeper is in a good state support under the track and prevent the sleeper pillow horizontal cracks appeared in the major conditions.</p><p>　　Stirrups and spiral reinforcement of the settings and preven

37、t sleeper End and central fracture cracks and nail holes, but not the overall stirrups itself, and is reinforced and priestesses loose lap, in the prevention of fracture in a limited effect. Some factories will be strict

38、ly end of the stirrups layout from the end of the first 30 mm, and priestesses reinforced Bingham firmly together, thus found to prevent the end of the fracture have a good effect.</p><p>　　Second, to streng

39、then production management and operation</p><p>　　After the 1990s, China's concrete sleeper factory's management of the operation by strict requirements, such as strict concrete mix to ensure that th

40、e vibration and dense concrete strength (including a tensile strength), in particular steam conservation. Stripping the surface with the sleeper when the ambient temperature difference between the ≤ 20 ~ 40 ℃, some facto

41、ries are still sleeper Stripping deposited within three days of water conservation. These measures to reduce the sleeper cracks, es</p><p>　　Third, strictly control the raw materials of concrete</p>&

42、lt;p>　　China's natural river sand has not found a base activity, but many regions of coarse aggregate base has potential activity, it should vigorously promote the use of low-alkali cement (alkali of ≤ 0.6%) and l

43、ow-alkali water reducer. In the current use of low-alkali cement and low-alkali super plasticizer still difficult circumstances, should control the largest amount of cement, concrete sleeper to make the alkali content do

44、es not exceed safety limits (3) o For example: When the cement alkali Volu</p><p>　　In short, the concrete in the early conservation, the main purpose is to maintain appropriate Temperature and Humidity cond

45、itions, so as to achieve the effect of both the one hand, the concrete from the adverse temperature and humidity deformation of the invasion, to prevent harmful Languor and shrinkage.</p><p>　　In theory anal

46、ysis, contained in the fresh concrete cement hydration water completely satisfy the requirements of a surplus. However, due to evaporation and other reasons often cause water loss, delay or prevent the hydration of cemen

47、t, concrete surface and easily the most directly affected by such adverse effects. Therefore concrete pouring is the first days after the critical period of conservation, in construction should be earnestly pay attention

48、 to it.</p><p>　　來源：(http://blog.sina.com.cn/s/blog_4e5c779201009atn.html) - Prestressed Concrete the extensive application o_軒轅靈兒_新浪博客</p><p><b>　　譯文：</b>&l

49、t;/p><p>　　預(yù)應(yīng)力混凝土的廣泛應(yīng)用</p><p>　　預(yù)應(yīng)力混凝土在使用荷載作用下作用于混凝土結(jié)構(gòu)，在生產(chǎn)階段，前階段的施加壓力的是由人工所造成的壓力。當(dāng)元件用來承受的負(fù)荷和壓力，首先要抵消預(yù)應(yīng)力混凝土，然后隨著負(fù)載的增加，混凝土產(chǎn)生應(yīng)力拉伸區(qū)。因此，混凝土裂縫可能會延遲出現(xiàn)，以滿足應(yīng)用的要求。在結(jié)構(gòu)構(gòu)件承受這個力會在之前加在預(yù)應(yīng)力混凝土結(jié)構(gòu)上，滿足預(yù)應(yīng)力混凝土結(jié)構(gòu)的要求。<

50、/p><p>　　中國的預(yù)應(yīng)力混凝土軌枕使用已經(jīng)超過30年，在對有關(guān)交通安全的損害上，通常被認(rèn)為把損壞的軌枕更換就行了。但是，為了換新的軌枕，除了重新制造，而且還需要處理，運(yùn)輸和安裝到線路上，不僅需要花費(fèi)大量的人力和物力，有時對交通的影響，成本往往是軌枕本身的費(fèi)用4至5倍。</p><p>　　作為預(yù)應(yīng)力的混凝土結(jié)構(gòu)軌枕，裂縫很難避免，了解預(yù)應(yīng)力的原因和裂縫的危險就如何預(yù)防和裂縫控制，對提高混

51、凝土軌枕結(jié)構(gòu)的耐久性，延長軌枕使用周期，是非常重要的。</p><p>　　1．混凝土軌枕軌枕裂縫的原因</p><p>　　混凝土裂縫的生成的研究是從結(jié)構(gòu)，工藝，材料和其他方面，或者是從設(shè)計，制造，鋪設(shè)，研究使用。在這里，只有從物理，化學(xué)，力學(xué)的角度來分析。</p><p><b>　　1.1機(jī)械因素</b></p><p

52、>　　混凝土軌枕不僅時刻遭受動態(tài)壓力，而且軌枕的端部有關(guān)。鋪設(shè)了原設(shè)計要求和保護(hù)應(yīng)該是空400空間，出于對軌枕的保護(hù)，最后掏空中間部分的軌枕應(yīng)小于30毫米，以避免負(fù)彎矩過大的枕頭橫向上裂。近年來，不需要中間掏空，中間應(yīng)墊壓載浮。假設(shè)，該軌枕的支持中部設(shè)計應(yīng)在3 / 4（中間挖空了）軌道的一部分。和一般混凝土軌枕從具體產(chǎn)品與不同國家支持的軌枕車的運(yùn)作和維修的條件不斷變化，曾經(jīng)支持國家和動壓震垂直懸掛由合并后的影響而產(chǎn)生超過設(shè)計極限，

53、目前，相應(yīng)的部分軌枕將有一個裂縫。此外，當(dāng)預(yù)加應(yīng)力時，偏載過大，混凝土強(qiáng)度不足，對軌枕底將有一個垂直的裂縫，鐵路列車的水平和垂直力的運(yùn)行并造成螺旋夾螺栓圍繞一個縱向和橫向裂縫螺栓孔。</p><p><b>　　1.2物理因素</b></p><p>　　物理因素是指軌枕生產(chǎn)和鋪設(shè)時凍融，凍結(jié)過程中的熱與冷，干，濕，凍結(jié)和融化作用。當(dāng)蒸汽升溫快，養(yǎng)護(hù)過程中的高溫恒溫時

54、，具體的煤氣，水，水泥，砂石等各種不同材料的熱膨脹系數(shù)不同，混凝土結(jié)構(gòu)的早期強(qiáng)度低，使高溫氣體和水大大擴(kuò)展，在混凝土內(nèi)部的具有缺陷導(dǎo)致松散的結(jié)構(gòu)，容易導(dǎo)致混凝土表面裂縫，特別是軌枕端面，很松散。</p><p>　　一段時間以來，許多工廠軌枕在蒸汽養(yǎng)護(hù)期間沒有預(yù)留停留時間，升溫快，恒溫器溫度高于95℃，在混凝土軌枕底部剝離腫脹，松散的情況常常發(fā)生。</p><p><b>　　1

55、.3化學(xué)因素</b></p><p>　　化學(xué)因素指鋼筋銹蝕，混凝土腐蝕，碳化，堿骨料反應(yīng)等。中國對混凝土軌枕研究中，堿骨料反應(yīng)（AAR的）造成的損害是不能被忽略的。堿骨料反應(yīng)的三個條件是：聚合活性，高堿水泥和水，這三個形成化學(xué)反應(yīng)，在混凝土和水泥界面聚合，對硅酸鹽凝膠形成更多的破壞，造成混凝土體積膨脹開裂。其中最常見的基地 - 硅酸反應(yīng)。</p><p>　　至于中國的很長一

56、段時間沒有限制堿水泥生產(chǎn)。使用高堿水泥增加水泥產(chǎn)量，減少成本。中國有一些地域的粗骨料（石）具有明顯的基礎(chǔ)活動，這兩者結(jié)合在一起，容易形成堿骨料反應(yīng)（AAR）破壞。這個問題從60年代末，一個預(yù)應(yīng)力混凝土的混凝土軌枕（橋梁）發(fā)生多次打擊骨裂，由于廠生產(chǎn)，加工，鋪設(shè)保護(hù)條件不足，進(jìn)一步提高斷裂，開裂，直到，80年代后期有開始我們必須承認(rèn)和肯定了試點(diǎn)。檢查過程是：首先是核心混凝土軌枕樣品，檢測項目，其中包括：①肉眼或使用立體顯微鏡，然后一邊超薄

57、反射鏡，由一般AAR的定期骨料顆粒損傷所造成的損害，從擴(kuò)展到漿聚合更多的裂縫，而且有時也明顯觀察分裂或破壞的邊緣。此功能是非常重要的，因為鹽腐蝕，化學(xué)腐蝕，耐腐蝕鋼，碳酸鹽，如機(jī)械載荷不會因受傷骨料顆粒，所以這是AAR和破壞的主要特點(diǎn)等因素，②有能力依靠耦合在電子顯微鏡可以測量頻譜分析堿硅酸鹽凝膠的化學(xué)成分，這是AAR的直接證據(jù)。此外，混凝土骨料機(jī)械和化學(xué)方法（通常用鹽酸處理）的分離，再利用和快速鑒別方法的逐步堿活性。</p>

58、;<p>　　總之，縱向裂縫是由于內(nèi)部因素（材料，結(jié)構(gòu)，技術(shù)因素），外部因素（加載和凍融，干濕循環(huán)）只有促進(jìn)其發(fā)展，橫向裂縫是內(nèi)部（預(yù)應(yīng)力混凝土鋼筋，混凝土強(qiáng)度）和（加載和軌枕邊界條件），外部因素組合造成的。</p><p>　　2．裂縫對混凝土軌枕結(jié)構(gòu)耐久性影響</p><p>　?。?）枕在露天環(huán)境中，因為是密實(shí)軌枕，水，氣體不會滲透到內(nèi)部，但在一定裂縫寬度和裂縫深度在保

59、護(hù)層里，水，天然氣將達(dá)到沿裂縫逐漸增強(qiáng)，導(dǎo)致鋼鐵腐蝕和生銹，鐵銹是一種鐵化合物（鐵氧化物），4倍與其體積膨脹引起混凝土內(nèi)部應(yīng)力，導(dǎo)致進(jìn)一步混凝土開裂，鋼筋和預(yù)應(yīng)力混凝土損害從而影響軌枕的承載能力。</p><p>　?。?）研究表明，出現(xiàn)一定的寬度的混凝土結(jié)構(gòu)裂縫，水，氣體可從鋼鐵腐蝕滲透。國內(nèi)和國際規(guī)范，鋼筋混凝土結(jié)構(gòu)，裂紋在0.1?0.3毫米（根據(jù)不同的環(huán)境），預(yù)應(yīng)力混凝土混凝土結(jié)構(gòu)甚至不允許裂紋，其目的是要

60、確保沒有鋼筋腐蝕。然而，很多時候在國內(nèi)和國外的調(diào)查和試驗，關(guān)系到裂縫寬度而不是直接關(guān)系到鋼鐵的腐蝕。</p><p>　?。?）研究也表明，一般結(jié)構(gòu)橫向裂縫比垂直裂縫的對總體結(jié)構(gòu)耐久性影響大。由于縱向鋼筋混凝土結(jié)構(gòu)裂縫會造成鋼筋腐蝕的保護(hù)層脫落，開裂混凝土膨脹會導(dǎo)致骨質(zhì)疏松，掉塊。筆者已經(jīng)從16個不同線路，不同國家的軌枕，逐軌道路是根據(jù)開裂靜強(qiáng)度和疲勞強(qiáng)度試驗。從測試結(jié)果可以看出：①通過在軌枕裂縫，對鐵路的一段最

61、靜載荷下裂強(qiáng)度明顯降低;②在骨折端或軌枕開裂，靜強(qiáng)度和疲勞開裂，比正常的軌枕，一般無顯著差異。這表明，該鐵路從表面裂縫和結(jié)束多裂紋，不影響混凝土和鋼筋的發(fā)展。</p><p>　　3.預(yù)防和控制混凝土軌枕裂縫</p><p>　　作為預(yù)應(yīng)力的混凝土軌枕結(jié)構(gòu)，要徹底消除裂縫是非常困難的事，裂縫是有害的?；谶@個原因，應(yīng)作出一切努力，防止裂縫的出現(xiàn)。裂縫的預(yù)防與控制，你可以從三個部分：<

62、/p><p>　　第一，從力學(xué)的角度來看，為了防止橫向裂縫，除按照以最大可能的負(fù)荷，合理配置預(yù)應(yīng)力鋼筋，我們還必須加強(qiáng)螺旋箍筋的和整個配置鋼筋夾螺栓。此外，為加強(qiáng)養(yǎng)護(hù)維修，軌枕在一個良好的狀態(tài)下，跟蹤支持，防止出現(xiàn)橫向裂縫在端頭的重要條件。螺旋箍筋的設(shè)置和加固，防止軌枕的終結(jié)和中央斷裂裂縫和釘孔，而不是本身的整體箍筋，是加強(qiáng)和預(yù)應(yīng)力混凝土松散圈在骨折預(yù)防，效果將很有限。一些工廠將嚴(yán)格的箍筋最后，從最終的布局前30毫米

63、，預(yù)應(yīng)力鋼筋固在一起，從而對防止斷裂有很好的影響。</p><p>　　第二，加強(qiáng)生產(chǎn)管理和經(jīng)營。</p><p>　　20世紀(jì)90年代，中國的混凝土軌枕廠的經(jīng)營管理有嚴(yán)格的要求，如嚴(yán)格的混凝土配合比，以確保振動和密集混凝土強(qiáng)度（包括抗張強(qiáng)度），特別是蒸汽養(yǎng)護(hù)。溶出軌枕時，表面之間溫差≤20?40℃，有些工廠在軌枕產(chǎn)出后用水降溫三天。這些措施，是以減少軌枕裂縫，裂縫和斷裂，特別是將是非常有

64、益的。</p><p>　　第三，嚴(yán)格控制混凝土的原材料</p><p>　　中國的天然河砂中還沒有找到一個基地，但粗骨料基地許多地區(qū)有潛力的發(fā)展，它應(yīng)該大力推動低堿水泥（≤0.6％堿）和低堿減水劑的使用。在低堿水泥和低堿高效減水劑目前仍然困難的情況下使用，應(yīng)控制最大的水泥量，混凝土軌枕，使堿含量不超過安全限度（3），例如：當(dāng)水泥堿量高達(dá)百分之一，水泥混凝土軌枕金額為500的，而500&#

65、215;1％= 5堿混凝土。超級增塑劑，如果不摻雜，已大大超過了安全極限3 的價值時，堿水泥量為0.6％，水的減速器堿百分之五，百分之一的金額的時間，為500×混凝土堿用量0.6％10500×1％×5％=3.25千克/立方米>3（安全限制），因此，當(dāng)金額最大的水泥混凝土減為460kg/m3時，因為460×0.6％×110460％×5％=2.99≈3的（安全限制），而不是通

66、常的技術(shù)條件規(guī)定的500。</p><p>　　總之，在早期養(yǎng)護(hù)混凝土，主要目的是保持適當(dāng)?shù)臏囟群蜐穸葪l件，以實(shí)現(xiàn)雙方的影響，一方面，從不利的溫度和濕度的侵襲變形混凝土，以防止有害倦怠和收縮。理論上分析，包含新拌混凝土水泥水化水完全滿足了剩余的需要。然而，由于蒸發(fā)等原因往往造成水分流失，延緩或防止水泥水化，混凝土表面，最容易直接受到這種不利影響。因此混凝土澆筑后的最初幾天的養(yǎng)護(hù)關(guān)鍵時期，在建設(shè)要切實(shí)重視起來。&l