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1、<p>  《寶鋼技術(shù)研究》2011年6月,第2期,??第24頁第5卷</p><p>  鋼渣透水混凝土的滲透系數(shù)影響因素的試驗(yàn)和分析</p><p>  楊剛,王友琴,王海龍,金強(qiáng)</p><p>  中國上海200941 SBMCC冶金渣研究中心</p><p>  摘要:鋼渣(SS)透水混凝土是由SS制備的,分析總水泥率,總

2、粒徑,水灰率,外加劑用量對SS透水混凝土的滲透系數(shù)的影響。規(guī)范的影響也被考察作為SS透水混凝土的設(shè)計(jì)和施工的技術(shù)參考。</p><p>  關(guān)鍵詞: 鋼渣 透水混凝土 滲透系數(shù) 影響因素 </p><p><b>  1引言</b></p><p>  隨著城市化的快速發(fā)展,普通混凝土一直被認(rèn)為是破壞城市生態(tài)系統(tǒng)的一種因素。相比與自然生態(tài)環(huán)境,

3、普通混凝土缺少雨水滲透能力、吸收熱量和自然呼吸作用。最重要的是在城市的地面上覆蓋著鋼筋混凝土建筑物和不透水的道路。因此,混凝土的可滲透性和可呼吸性已成為建筑行業(yè)的重點(diǎn),引起了人們的關(guān)注。鋼渣(SS)是一種轉(zhuǎn)換器或電弧爐(EAF)產(chǎn)生的工業(yè)固體廢物。SS是具有類似自然資源的化學(xué)成分和物理性質(zhì)的鋼渣,經(jīng)過適當(dāng)?shù)臒崽幚恚↙500℃以上),快速冷卻和加工凝固,其具有穩(wěn)定性好,硬度高,耐磨損,易分離等諸多特點(diǎn)。因此,SS可以被應(yīng)用到許多領(lǐng)域。&l

4、t;/p><p>  目前,透水混凝土(又稱多孔混凝土,大孔混凝土等)的新型建材產(chǎn)業(yè)已成為一個(gè)熱門話題。也有許多相關(guān)的研究報(bào)告。其中研究員,同濟(jì)大學(xué)陳志珊教授和長安大學(xué)甄慕蓮教授做大量的SS透水混凝土的深入研究,他們分別提出了測試SS透水混凝土滲透性的方法。不過,關(guān)于SS透水混凝土的報(bào)道較少。本研究主要是調(diào)查和分析影響SS透水混凝土滲透系數(shù)的因素,其中包括骨料總粒徑,水泥率,外加劑用量,水膠率等各種因素。</p

5、><p><b>  2原料</b></p><p>  來自寶鋼轉(zhuǎn)換器的1-3毫米,3-5毫米,5-10毫米,10-20毫米四種不同尺寸的SS的樣品原料分別被編號(hào)為A,B,C和D。上海海豹水泥(集團(tuán))有限公司生產(chǎn)的水泥是42.5級(jí)普通硅酸鹽水泥。添加劑是鋰二異丙基氨基添加劑(LDA)。</p><p><b>  3試驗(yàn)方法</b

6、></p><p>  3.1用于測量滲透系數(shù)的設(shè)備</p><p>  透水設(shè)備自行設(shè)計(jì)和制作,如圖1所示。</p><p>  圖1 測量滲透率透水設(shè)備示意圖</p><p>  該裝置由一個(gè)大小為150㎜×150㎜×300㎜玻璃箱組成,其頂部是開口的,在底部有一個(gè) 80㎜的空。在測試過程中用于測量的一側(cè)每級(jí)

7、50㎜已經(jīng)過校準(zhǔn)。</p><p><b>  3.2測試過程</b></p><p>  在測試之前,把樣品側(cè)表面用密封材料或其他材料密封起來,為了防水和使水只能通過上下表面滲透。樣品被測試端上的膩?zhàn)用芊?。放在密封樣品和使用膩?zhàn)由厦娴耐杆O(shè)備是為了收緊的樣品和設(shè)備以及刮掉底部多余的膩?zhàn)?。?50㎜級(jí)的透水設(shè)備中加入水(清水)。當(dāng)水位下降到100㎜時(shí)用秒表定時(shí)倒計(jì)時(shí),

8、當(dāng)水位達(dá)到200㎜級(jí)的計(jì)時(shí)停止。</p><p><b>  3.3計(jì)算結(jié)果</b></p><p>  SS透水混凝土的滲透系數(shù)(由V表示),可以由下列公式(1)計(jì)算。</p><p><b>  (1)</b></p><p>  其中H表示水平面下降的高度(100毫米);表示水位從200毫米/

9、秒下降至l00毫米/秒的時(shí)間所用的時(shí)間。</p><p>  計(jì)算結(jié)果是三個(gè)樣本準(zhǔn)確到0.1毫米/秒時(shí)的平均值。</p><p><b>  4結(jié)果與討論</b></p><p>  4.1骨料粒徑和水泥率對滲透系數(shù)的影響</p><p>  用四個(gè)不同規(guī)格的SS樣品作為骨料,來制備0.22, 0.24,0.26,0.2

10、8,0.30和0.32不同水灰率的SS透水混凝土,以測試他們的滲透系數(shù)。</p><p>  從圖2顯示的結(jié)果中我們可以看到所有SS透水混凝土的滲透系數(shù)均在1?15毫米/秒范圍內(nèi)。在同等條件下,樣品A相比與樣品D,滲透系數(shù)隨著總尺寸的增加而增加。例如,水灰率為0.22時(shí),粒徑為1-3mm骨料透水混凝土和粒徑為10-20毫米骨料透水混凝土的滲透系數(shù)分別為5.9毫米/ s和13.3毫米/秒,增加的比例分別為125%,

11、表明增加是顯著的。這是因?yàn)殡S著總尺寸的增加,孔隙率增大,滲透系數(shù)也增加。</p><p>  實(shí)驗(yàn)表明,無論什么規(guī)格的SS透水混凝土隨著水灰率的增加SS透水混凝土的滲透系數(shù)降低。然而,當(dāng)水灰率是0.22和0.26之間,滲透系數(shù)下降并不明顯。水灰率是0.28和0.32之間時(shí),滲透系數(shù)下降是非常明顯的。拿樣品C為例,水灰率從0.22提高到0.26時(shí),滲透系數(shù)從9.2毫米/秒降低到7.8毫米/秒,下降的百分比是15.2

12、%。由于水灰率從0.28提高到0.32,滲透系數(shù)從6.9毫米/秒減小到3.9毫米/秒,下降的百分比是43.5%。主要的原因是隨著水灰率的增加SS透水混凝土表面的漿也增加造成表面堵塞和孔隙率降低。</p><p><b>  水灰比</b></p><p>  圖2 SS透水混凝土的滲透系數(shù)和水灰率之間的關(guān)系</p><p>  4.2骨料

13、灰率對滲透系數(shù)的影響</p><p>  骨料灰率是SS骨料和膠凝材料在SS滲透性混凝土所含的比率,總水灰率可以通過水泥用量來調(diào)節(jié)。這些研究表明,當(dāng)骨料灰率在3.0-8.0范圍內(nèi)時(shí),混凝土的強(qiáng)度可以達(dá)到C40-C15;當(dāng)骨料灰率大于8.0時(shí),養(yǎng)護(hù)28天的混凝土的強(qiáng)度也低于C15。因此,我們選擇了8.0,7.0,6.0,5.0,4.0,3.0的總水泥率實(shí)驗(yàn)和分析。</p><p>  從圖3

14、中可以看出,SS的透水混凝土增加的滲透系數(shù)隨著總灰率的增加,從3.0增加到了8.0。因?yàn)楫?dāng)總灰率較低時(shí),隨著水泥的比例增大,試樣的強(qiáng)度相應(yīng)增高;但如果水泥包裝中的SS顆粒變得過多造成SS透水混凝土的孔隙率降低,滲透性也隨之降低。此外,當(dāng)粒徑很小時(shí),隨著總水灰率下降滲透性會(huì)迅速降低。例如,當(dāng)骨料粒徑為3毫米和5毫米之間時(shí),總灰率從8.0下降到3.0,滲透系數(shù)從9.7毫米/秒降低到1.1毫米/秒,下降的百分比是88.7%。</p>

15、;<p><b>  骨料和水泥的比例</b></p><p>  圖3 總灰率和SS透水混凝土的滲透系數(shù)之間的關(guān)系</p><p>  4.3外加劑用量對滲透系數(shù)的影響</p><p>  然而,圖4表明,在限定的范圍內(nèi)在SS上外加劑的用量對SS透水混凝土具有一定的影響。SS透水混凝土的滲透系數(shù)隨外加劑用量的增加而增加。鑒于其他

16、因?qū)俨蛔兊那疤嵯?,減少外加劑的用量,將有助于增加SS透水混凝土的滲透系數(shù)。</p><p><b>  外加劑用量/%</b></p><p>  圖4 外加劑的用量對SS透水混凝土的滲透系數(shù)的影響</p><p>  4.4其他因素的影響滲透系數(shù)</p><p>  除了上述的主要因素,以下條件可能會(huì)影響SS透水混凝

17、土的滲透系數(shù):</p><p>  (1)溫度越低,水的動(dòng)力粘度系數(shù)越大,滲透系數(shù)越小。把20℃作為標(biāo)準(zhǔn)溫度,在方程(1)中,溫度T可以轉(zhuǎn)換成標(biāo)準(zhǔn)溫度下的滲透系數(shù)。</p><p><b>  (2)</b></p><p>  是在20℃的滲透系數(shù),是在T(℃)的滲透系數(shù), 是在T(℃)的動(dòng)力粘度系數(shù),(kPa·s)是在20℃的動(dòng)力

18、粘度系數(shù)。和,常數(shù)可以從“公路土壤試驗(yàn)規(guī)范”中查取。</p><p>  (2)其次,攪拌的均勻程度也是滲透系數(shù)的因素之一。因?yàn)楫?dāng)骨料的水灰率較低時(shí),施工的速度,周圍的環(huán)境和養(yǎng)護(hù)條件也都能影響SS透水混凝土滲透系數(shù)。</p><p><b>  5 結(jié)論</b></p><p>  SS透水混凝土的滲透系數(shù)隨著骨料總顆粒和水灰率的增加而增加。當(dāng)

19、骨料粒徑較小時(shí),滲透系數(shù)隨著總灰率下降迅速降低。</p><p>  SS透水混凝土的滲透系數(shù)隨著水灰率的增加而降低。當(dāng)水灰率在0.22和0.26之間時(shí),滲透系數(shù)隨著水灰率的增加下降不明顯;水灰率在0.28和0.32之間時(shí),滲透系數(shù)隨著水灰率的增加下降顯著。隨著摻合料用量的增加, SS透水混凝土的滲透系數(shù)減小,但影響是有限的。</p><p>  其他因素也能影響SS透水混凝土的滲透系數(shù)。

20、所以在實(shí)際施工過程中,工作人員應(yīng)遵守規(guī)范的要求,以降低滲透系數(shù)的波動(dòng)。</p><p><b>  參考文獻(xiàn)</b></p><p>  [1]章輝,張謇與金強(qiáng)。礦渣細(xì)粉寶鋼鋼材的膠凝材料的穩(wěn)定性和兼容性的研究[J]。寶鋼技術(shù)研究,2009,3(4);28-32。</p><p>  [2]甄慕蓮。參透系數(shù)和多孔混凝土的試驗(yàn)方法研究[J]。 交

21、通運(yùn)輸工程,2006,4(11);41-46。</p><p>  [3]金強(qiáng),何紅珠,楊剛。資源利用寶鋼渣作為混凝土材料研究[J]。寶鋼技術(shù),2010(3);19-22。</p><p>  Baosteel Technical Research</p><p>  Volume5,Number2,June2011,Page24</p><p&

22、gt;  Test and analysis of influencing factors on the permeability coefficient of steel slag permeable concrete</p><p>  YANG Gang, WANG Youqin,WAN G Hailong and JlN Qiang</p><p>  Research Cente

23、r of Metallurgical Slag,SBM CC,Shanghai200941,China</p><p>  Abstract:The steel slag (SS) permeable concrete was prepared by SS.The influences of the aggregate-cement rate,the aggregate particle size,the wat

24、er-cement rate,the admixture dosage and other factors on the permeability coefficient of SS permeable concrete were analyzed.The law of influence was also investigated.The study serves as a technological reference for th

25、e construction and design of SS permeable concrete.</p><p>  Key words:steel slag;permeable concrete;permeability coefficient;influencing factors</p><p>  1 Introduction </p><p>  W

26、ith the rapid development of urbanization,ordinary concrete has been considered the cause of destruction of an urban ecosystem .Compared with the natural ecological environment.the general concrete lacks the ability of r

27、ainwater permeability.a(chǎn)bsorbing heat and natural breathing.Most of the ground in an urban city is covered with reinforced concrete buildings and impermeable roads.Therefore,the concrete that can permeate and breathe has

28、become the focus of and grabbed attention from the building</p><p>  Currently.Permeable concrete(also known as porous concrete,big-hole concrete,etc.)has become a hot topic in the new building materials ind

29、ustry.There are also many related research reports. Among the researchers.Professor CHEN Zhishan in Tongji University and Professor ZHEN Mulian in Chang’an University have done a considerable amount of in-depth research

30、on the SS permeable concrete,and they have individually proposed the method to test the permeability of SS permeable concrete.However,there ar</p><p>  mainly investigates and analyzes the various factors in

31、fluencing the permeability coefficient of SS permeable concrete,which includes the aggregate particle size,the aggregate—cement rate,the admixture dosage, and the water—cement rate. </p><p>  2 Raw materials

32、 </p><p>  1—3 mm ,3—5 mm ,5—10 mm ,10—20 mm of four different sizes of SS from Baosteel’s converters were used as the raw materials,and the prepared samples were numbered A ,B,C and D.Cement produced by Sha

33、nghai Haibao Cement(Group)Co., Ltd.was42.5 grade Portland cement.Additive was Lithium diisopropylamide additive (LDA ).</p><p>  3 Test methods </p><p>  3.1 Equipment used to measure permeabil

34、ity coefficient</p><p>  The permeable device was designed and manufactured by ourselves,as shown in Fig.1.</p><p>  Fig.1 Schematic diagram of the permeable device to measure permeability</p

35、><p>  This device consists of a glass box,whose size is 150㎜×150㎜× 300㎜.Its top is open and has a ?Φ80㎜ hole in the bottom.This device has calibrated of 50㎜ per grade on one side, which is used for M

36、easurement during testing.</p><p>  3.2 Testing procedures</p><p>  Before being tested, the sample was scaled on all sides with sealing materials or other materials in order to make it waterti

37、ght and water can only infiltrate through the upper and lower surfaces.The sample was sealed with putty on the testing side.The permeable device was placed above the sealed sample and the putty was used in order to tight

38、en the sample and the device and the excess putty in the bottom circle was scraped.The water (clean water)was added into the permeable device to the 250㎜gr</p><p>  3.3 Calculation of results</p><

39、p>  The permeability coefficients (branded by V)of SS permeable concrete can be calculated by the following Equation (1).</p><p><b>  (1)</b></p><p>  Where H is the height of the

40、 water level dropped (100 mm); the time for the water level to drop from 200 mm/s to l00 mm/s.Results are the average value of the three samples and calculation is as accurate as 0.1 mm/s.</p><p>  4 Results

41、 and discussion </p><p>  4.1 Influence of aggregate particle size and water-cement rate on the permeability coefficient</p><p>  The four SS samples with different specifications were used as

42、aggregate and the SS permeable concrete was made with different water-cement rate:0.22,0.24, 0.26, 0.28, 0.30 and 0.32 in order to test their permeability coefficients.</p><p>  The results are shown in Fig.

43、2.We can see that the permeability coefficients of all SS permeable concretes are in the range of 1~15 mm/s.Under the same conditions, the permeability coefficient increases with the aggregate size increasing when Sampl

44、e A js compared with Sample D.For example.when the water-cement rate is 0.22, the permeability coefficient of the 1—3mm aggregate permeable concrete and the 10—20 mm aggregate permeable concrete were 5.9 mm/s and 13.3 ra

45、m/s, respectively, and the pe</p><p>  The research shows that the permeability coefficient of SS permeable concrete reduces as the water—cement rate increases,no matter what the specifications of the SS a

46、re. However.when the water—cement rate is between 0.22 and 0.26,the decrease of the permeable coefficient is not obvious. when the water—cement rate is between 0.28 and 0.32, the decrease of the permeable coefficient is

47、very obvious.Take Sample C as an example,as the water—cement rate increases from</p><p>  0.22 to 0.26.the permeability coefficient decreases from 9.2 mm/s to 7.8 mm/s and the percentage of the descent is 15

48、.2% .As the water—cement rate increases from 0.28 to 0.32, the permeability coefficient decreases from 6.9 mm/s to 3.9 mm/s, and the percentage of the descent is 43.5%. The main reason is that as the water—cement rate i

49、ncreases,the slurry on the SS permeable concrete’s surface increases too, causing the surface blocked and the porosity decreased.</p><p>  Water-cement ratio</p><p>  Fig.2 Relationship between

50、 permeability coefi cient and water-cementrate of SS perm eable concrete</p><p>  4.2 Influence of aggregate-cement rate on permeability coefficient</p><p>  The aggregate—cement rate is the rat

51、e of SS aggregate and cementitious material in SS permeability concrete, which can be achieved by adjusting the amount of cement.These studies have shown that the strength rating can be C40 —C15 when the aggregate, cemen

52、t rate is in the range of 3.0—8.0; and 28 d strength wil1 be less than C15 when the aggregate-cement rate is above 8.0.So we chose 8.0,7.0,6.0 5.0,4.0, 3.0 as their aggregate-cement rates for the test and analysis.</p

53、><p>  From Fig.3.it can be seen that the permeability coefficient of SS permeable concrete increases with the increase of the aggregate-cement rate from 3.0 to 8.0.Because when the aggregate-cement rate is low

54、er, the percentage of cement is </p><p>  Aggregate—cement ratio</p><p>  Fig.3 Relationship between the aggregate-cement rate and the permea

55、bility coefficient of SS permeable concrete</p><p>  relatively larger and the strength of the specimen is higher accordingly;but the cement wrapping the SS particles becomes excessive, causing the porosity

56、of SS permeable concrete to decrease.a(chǎn)nd the permeabi1ity coefficient to decrease as wel1.In addition,when the particle size is smal1, the permeability coefficient quickly decreases with the decrease of the aggregate-cem

57、ent rate.For example, when the aggregate size is between 3mm and 5 mm, the aggregate-cement rate decreases from 8.0 to 3.0, t</p><p>  4.3 Influence of admixture dosage on permeability coefficient</p>

58、<p>  Fig.4 shows that the amount of admixture dosage on the SS has a certain influence on SS permeable concrete.however.to a 1imited extent.The permeability coefficient of SS permeable concrete decreased with the

59、 increase of the admixture dosage. Given the premise of other properties,reducing the admixture dosage will be helpfu1 to increase the permeability coefficient of SS permeable concrete.</p><p>  Admixture do

60、sage/%</p><p>  Fig.4 Effect of the admixture dosage on the permeability coefficient of SS permeable concrete</p><p>  4.4 Influence of other factors on the permeability coefficient</p>&

61、lt;p>  Besides the main factors mentioned above,the following conditions may affect the permeability coefficient of SS permeable concrete:</p><p>  (1) The lower the temperature is and the greater the wat

62、er’s dynamic viscosity coefficient is, the smaller the permeability coefficient is.Making 20 ℃ the standard, Equation(1)when the temperature is T can be converted to coefficient permeability at the standard temperature.&

63、lt;/p><p><b>  (2)</b></p><p>  Where is the permeability coefficient at 20℃;,the permeability coefficient at T(℃);,the dynamic viscosity coefficient at T(℃) and (kPa·s), the dyna

64、mic viscosity coefficient at 20℃ .a(chǎn)nd ,constant values can be consulted from “Highway soil experiment specification.</p><p>  (2) In addition,the degree of mixing uniformity . Because when the aggregate-cem

65、ent rate is lower,the speed of construction progress,the surrounding environment and curing conditions can also influence the permeability coefficient of SS permeable concrete.</p><p>  5 Conclusions</p&g

66、t;<p>  (1)The permeability coefficients of SS permeable concrete are increased with the increase of the aggregate particle and the aggregate-cement rate.When the particle size is small,the permeability coefficien

67、t quickly decreases with the decrease of the aggregate-cement rate.</p><p>  (2)Permeability coefficients of SS permeable concrete are reduced with the increase of the water-cement rate.As the water cement r

68、ate is between 0.22 and 0.26, the permeable coefficient declines inconspicuously and when the water-cement rate is between 0.28 and 0.32, the permeable coefficient declines obviously.As the admixture dosage increases,the

69、 permeability coefficient of SS permeable concrete decreases, but the influence is limited.</p><p>  (3)Other factors also influence the permeability coefficient of SS permeable concrete.So in practical cons

70、truction processes,workers should abide by the standard requirements in order to reduce the volatility of the permeability coefficient.</p><p>  References</p><p> ?。?] ZhangHui,Zhang Jian and J

71、in Qiang.Research on the stability and compatibility of the cementitious materials of Baosteel steel slag fine powder [J].Baosteel Technical Research,2009,3(4):28—32.</p><p> ?。?] Zhen Mulian.Permeability co

72、efficient and its test method of porous concrete [J]. Journal of Traffic and Transportation Engineering,2006,4(11);41—46.</p><p>  [3] Jin Qiang,He Hongzhu and Yang Gang.Resource utilization of Baosteel slag

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