建筑材料外文翻译doc.docx

1、建筑材料外文翻译doc外文翻译对普通硅酸盐水泥和粉煤灰的物理性能和力学性能的研究摘要 对高掺量粉煤灰硅酸盐水泥做了一个实验，来对它的物理和力学性能进行研究。普通硅酸盐水泥分以0,20、30、40、50、60、70%几个等级分别被粉煤灰取代（按重量计算）。在所有的混合物中，水胶比恒定为0.3。试块在振动台上被振实。预期的体积密度会随着粉煤灰掺量的增加而减少。气孔率和吸水率会随着水泥被粉煤灰取代而增大。添加了粉煤灰试块的3d、7d，28d的抗压强度降低了，这一点在假设粉煤灰掺量在30%以上的实验中更加明显。超声波脉冲速度测试结果表明，浆体的性能会随着混合物中粉煤灰掺量的增加而降低。关键词：粉煤灰，

2、抗压强度，超声波脉冲检测技术，水泥1 介绍 每年印度的火力发电产能生产超过1.6亿吨的粉煤灰。对于火力发电厂来说，处理粉煤灰是一个很重要的问题。通常的，现在大量的飞灰和底灰在土地里会被用来阻塞和填充，以最小化的成本处理。在1985年，加拿大的自然资源部首先调查发现：大量的粉煤灰具有许多优异的性能，各种标准规范规定在水泥行业粉煤灰的掺量不能超多35%。在印度,水泥和混凝土行业每年消耗4000万吨粉煤灰。另一个方面，水泥需求的不断上升可以进一步解决高掺量粉煤灰（超过50%）在混凝土上面的应用。这个过程显然可以经济化，以及减少温室气体(GHG)的排放,减少废物处置和减少健康的危害。因此在混凝土中使用

3、高掺量粉煤灰开始兴起，对普通硅酸盐水泥(OPC)混凝土应用程序，是一个资源节约型、耐用、成本效益的、可持续的选择 (克劳奇,lK理论研究。2007)。这项工作的目的是研究一些物理和机械属性，如容重、孔隙率、吸水率和超声波脉冲速度和抗压强度的粉煤灰硅酸盐水泥。2 材料和方法2.1 材料 普通硅酸盐水泥(OPC)28天抗压强度使用54 MPa。普通硅酸盐水泥的主要性质见表1。粉煤灰来自西孟加拉、印度的火力发电厂。水泥和粉煤灰的化学成分见表2. 粉煤灰包含非常少碳含量，正如所指出的那样,低价值的损失在点火(LOI)。粉煤灰的硅铝比(SiO2/Al2O3)为2.5，二氧化硅,氧化铝和Fe2O3的总和等

4、于95.74%。氧化钙含量小于1%。因此,按标准ASTM C 618 08，它可以分为类F粉煤灰。按照国际标准，3182-2003，它可分为硅质粉煤灰。粉煤灰的粒子大小分布为图一，粉煤灰为深灰色的颜色，混合物的用水为正常的饮用水。表1:普通硅酸盐水泥的主要性质细度比表面(m2/kg)312凝结时间(minutes)初凝180终凝290标准稠度(%)31.5表二：普通硅酸盐水泥和粉煤灰的化学性质SiO2Al2O3Fe2O3CaOMgOK2ONa2OSO4LOI*OPC（%）18.624.753.0261.423.211.421.512.293.55Fly Ash（%）64.5825.895.27

5、0.590.260.0410.0270.312.40粒子大小、微米图一 ：粉煤灰的粒度分布2.2 混合设计和样品制备 表3代表了不同混合物中不同粉煤灰比例的浆体，控制的混合物没有掺粉煤灰标记为F0和20 - 70%的OPC，已经被粉煤灰取代的分别标记为F20-F70,水胶比还是保持在0.3.准备好边长50mm的立方体试模，高频振动台，进行正常压实。每组混合物准备十八个试模，进过二十四小时的养护，从试模中取出试块，保持其湿度并在室温25进行实验，抗压轻度值取六个的平均值。表3 OPC和Fly Ash混合浆体的成分成分F0F20F30F40F50F60F70OPC100807060504030FL

6、Y ASH0203040506070水胶比0.30.30.30.30.30.30.32.3 实验程序 在水中养护7天后，测试其容重、气孔率、孔隙率和超声波脉冲速度，确定容重、气孔率和吸水率。从每个组里面的取三个试块在110的干燥箱里进行干燥，24小时后取出称其干重(DW)。这个试块被放在水里煮沸2个小时，另一个则放在相同温度下的水中24小时，来让水渗入到毛细孔中。然后用0.5mm的铜线把试块悬挂在水中，测定它的悬浮重量(S1 W)和以及浸泡质量(S2 W)，记录数据时要细心，要除去试块表面的水和铜线的质量。下面的方程被用来计算样品的气孔率和吸水率。容重（gm/cc)=气孔率(%)=孔隙率(%)

7、=3. 结果和讨论 图二表示被粉煤灰取代的样品的不一样的体积密度，结果发现，水泥（1.33gm/cc）的容重比粉煤灰（0.96gm/cc）的容重高得多。正如之前所预期的，样品的体积密度会随着混合物粉煤灰掺量的增多而减少。 图二 不同粉煤灰掺量下样品的容重 图三和图四分别表示样品的气孔率和吸水率，很明显孔隙率和吸水率在随着粉煤灰掺量的增加而增大。这个结果表明粉煤灰对粉煤灰的微观结构的研究比较缺乏。图三 不同粉煤灰掺量下样品的孔隙率图四 不同粉煤灰掺量下样品的吸水率 通过采用标准13311 (Part 1) 1992中提到的方法完成了超声波脉冲速度测试，通过这个测试来评定样品的质量。这个测试结果显

8、示,所有UPV试样落在“好”的类别。结果证实了粉煤灰增加，而UPV质量则下降。表4:样品的超声波脉冲速度试验结果(公里/秒)粉煤灰含量(%)0203040506070UPV3.783.743.733.683.643.583.55抗压强度是使用压力试验机来进行试验。我们看到实验的结果是平均抗压强度的值是在反抗粉煤灰掺量的增加。结果证明样品的3d、7d、28d抗压强度随着粉煤灰掺量的增加而降低（图五）。当粉煤灰含量在60%以上是抗压强度下降的趋势是最为明显的。从实验结果来看最优的是粉煤灰掺量在60%（最大）。OPC中掺粉煤灰可以用于一些低强度混凝土和砌体工程。这将直接降低建筑成本以及减少温室气体的

9、排放。图五：粉煤灰样品的抗压强度4 结论根据目前的研究,可能得出的结论是：在普通硅酸盐水泥中掺入粉煤灰会降低其28天的抗压强度。当粉煤灰的掺量大于30%时抗压轻度会急剧下降。凝结反应需要时间，有时强度可能会增大，所以长期的研究是必要的的。粉煤灰的添加会降低容重，这会增加土木工程师对建设轻重量建筑的兴趣。其他的物理性质，比如：孔隙率和吸水率的增加会降低掺加了粉煤灰混凝土的耐久性。UPV的实验结果表明高含量的粉煤灰会降低抗压强度。5 致谢印度新德里科学技术部的对这个实验研究提供了经济支持。参考文献 1.k . Jain(2011),混凝土可持续发展通过创新材料和技术全国巡回研讨会pp 46-51。

10、 2.ASTM C618 - 08 a,(2008),、美国试验材料学会、美国。3.Bumjoo金,莫尼卡Prezzi(2008),。4.克劳奇,休伊特,白阿德(2007),程序上的煤灰(WOCA),美国肯塔基州pp1 - 14。5.规范:3812(第一部分)。(2003)、粉煤灰-规范-第1部分:粉煤灰用作火山灰水泥,水泥砂浆和混凝土印度,新德里标准。6.规范：13311(第1部分)(1992),:第1部分超声波脉冲速度、印度新德里标准。7.马尔霍特拉。(1986),混凝土国际、8(28),pp28-31。Study on the physical and mechanical proper

11、ty of ordinary portland cement and fly ash pasteABSTRACT An experimental investigation has been carried out to study the physical and mechanical property of high volume fly ash cement paste. Ordinary portland cement was replaced by 0,20, 30, 40, 50, 60 and 70 % class F fly ash (by weight). Water- bi

12、nder ratio in all mixture was kept constant at 0.3. Cube specimens were compacted in table vibrator. As expected bulk density decreases with fly ash increment in the mixture. Apparent porosity and water absorption value increases with replacement of cement by fly ash. Results confirm the decrease in

13、 compressive strength at 3, 7 and 28 day with fly ash addition and it is more prominent in case of more than 30% fly ash content mixes. Ultrasonic pulse velocity test results indicate that the quality of the paste deteriorate with increase of fly ash content in the mixture.Keywords: Fly Ash, OPC, Co

14、mpressive Strength, Pastes, UPV.1. Introduction More than 160 million tonnes of fly ash is being produced by thermal power plant in India(A. K. Jain, 2011). The disposal of fly ash is now a significant concern for the electricity manufacturing plants. Commonly, huge volume of fly ash and bottom ash

15、are now being either ponded or used as land filling to minimize the disposal cost (Bumjoo Kim and Monica Prezzi, 2008). In the year 1985 CANMET first investigate and confirmed that high volume of fly ash has many excellent properties (V.M. Malhotra, 1986). Various standard codes limited the use of q

16、uality fly ash up to 35% in cement industry. In India, cement and concrete industry consumes about 40 million tonnes of fly ash . On the other hand, the rising of cement demand can be further resolved by utilizing high volume (more than 50 %) of fly ash in the concrete. This process obviously will b

17、e economical as well as reduce greenhouse gas (GHG) emission, minimize waste disposal and health hazards. Thus the use of high volumefly ash in concrete has recently gained popularity as a resource-efficient, durable, costeffective, sustainable option for ordinary portland cement (OPC) concrete appl

18、ications (Crouch, L. K et.al. 2007). The aim of this work is to study some physical and mechanical properties such as bulk density, apparent porosity, water absorption and ultrasonic pulse velocity and compressive strength of ordinary portland cement- fly ash pastes (without any aggregate).2. Materi

19、als and Method2.1 Materials Ordinary Portland Cement (OPC) having 28 day compressive strength of 54 MPa was used. Typical properties of the OPC used are given in table 1. The fly ash was collected from National Thermal Power Plant, Farakka, West Bengal, India. Chemical composition of both cement and

20、 fly ash is shown in table 2. The fly ash contains very less carbon content as indicated by the low value of loss on ignition (LOI). Silica to alumina ratio (SiO2/Al2O3) of the fly ash was 2.5.The sum total of SiO2, Al2O3 and Fe2O3 equal to 95.74%.Calcium oxide (CaO) content was less than 1%. Hence,

21、 as per ASTM C 618-08, it can be classified as class F fly ash. Based on IS: 3812 (Part I)-2003 it can be classified as siliceous pulverized fuel ash. The particle size distribution of fly ash has been given in Figure 1. The fly ash showed a dark gray colour. Normal potable water was used in making

22、the mixture。2.2 Mix Design and Specimens Preparation Table 3 represents the mixture proportion of different fly ash-cement pastes. The control mixture without fly ash has been marked as F0 and 20 to 70% OPC have been replaced by fly ash and marked as F20 to F70 respectively. The water- binder ratio

23、was kept constant at 0.3.Specimens of 50mm cubes were prepared and properly compacted with high frequency vibrating table. Eighteen cubes were cast for each mixture. After 24 hours of casting, the cubes were removed from the mould, and were cured in water at ambient temperature of 25OC till testing.

24、 The compressive strength value for a typical mixture at a particular age is based on the average of six cubes.2.3 Test procedure Bulk density, apparent porosity, water absorption and ultrasonic pulse velocity has been measure after 7 day water curing. To determine the bulk density, apparent porosit

25、y and water absorption of the fly ash-cement paste specimens, three cubes from each series were dried in hot air oven at 110OC for 24 hours and its weight was taken as dry weight (DW). The specimens were then boiled in water for 2 hours and kept for another 24 hours in the same warm water to penetra

26、te water in the pores. Specimens were then suspended in water with copper wire of 0.5 mm thickness to take the suspended weight (S1 W) as well as soaked weight (S2 W) was also recorded by carefully removing the surface water and the copper wire. The following equations were used to find out the appa

27、rent porosity and water absorption of the specimens.3. Results and Discussions Figure 2 represent the bulk density of different OPC replaced fly ash paste specimens. It was found that the bulk density of the cement was much higher (1.32 gm/cc) compare to fly ash (0.96 gm/cc). As expected, the bulk d

28、ensity of the specimens decreases with increase of fly ash in the mixture.Figure 3 and Figure 4 represent the apparent porosity and water absorption of the specimens.Both the apparent porosity and water absorption value increased with fly ash replacement.This result indicates the poor microstructure

29、 with high amount of fly ash pastes.Ultrasonic pulse velocity test has been done to assess the quality of paste specimens by method mentioned at IS: 13311 (Part 1) 1992. It is evident from the UPV test results that all the test specimens fall in “GOOD” category. With fly ash increase the UPV results

30、 confirms the deterioration in quality.The compressive strength was determined using a digital compression testing machine. The maximum load at failure reading was taken and the average compressive strength has been plotted against fly ash content. It is evident that the compressive strength of the

31、specimens decreases with increase of fly ash in the mixture at 3, 7 and 28 day (Figure 5). The drop in compressive strength is prominent when fly ash content in the mix increased above 30%. From the experimental result optimally 60% (max.) fly ash content OPC can be used for some low strength concrete and masonry works. This will directly reduce the cost of construction as well as reduce the green house gas emission.4. ConclusionOn the basis of the pre