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冰儿
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- 2007-03-20
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发表于 2007-12-04 21:49
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砼随着材料的开发及应用,砼组成材料由普通砼的水泥、砂、石、水四种发展为5~7种组成材料,使影响砼强度及工作性等的因素变得更复杂,这就为砼配合比的确定提出了新的要求.配合比的确定,关键是要保证砼满足施工、强度、耐久性、经济性四方面要求.在现行配合比设计规程JGJ/T55-96中,高强砼配合比确定方法基本上还采用普通砼的确定方法.但在实践中,该方法已显不足.h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 1 现行的高强砼配合比确定方法h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 高强砼配合比的确定现在基本是应用普通砼的确定方法.该方法是利用鲍罗公式及表格按强度及耐久性要求确定水灰比 ;按粘聚性要求确定砂率Sp;按流动性要求确定单位用水量W0;按经验确定外加剂掺量及掺合料用量;按以上确定参数计算初步配合比;然后进行试拌,按工作性好坏,对Sp、W0及外加剂等作适当调节;最后利用 ~f的线性关系进行强度调节确定配合比.这方法以其简单易行一直被人们所应用[2].h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 2 在普通砼及高强砼中,用料及配合比关键参数对性能的影响的差别[1~3]h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 2.1 水灰比 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 1)在原材料一定的条件下,在普通砼中, 对强度起决定性作用.因此,在确定 时,除考虑耐久性外,主要由强度确定;而在高强砼中,除 外,骨料含量、砂率、单位用水量等对强度也影响较为显著.h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 2)在普通砼中,灰水比 与砼强度f的关系为线性关系,在进行砼试配时,正是利用了此关系进行强度调整;而在高强砼中,当 较小时, ~f的线性关系反常.h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 2.2 砂率Sp的影响h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 在普通砼中,Sp对强度影响很少,对粘聚性影响十分显著,随着Sp增大,粘聚性变好.因此,在确定砼配合比时,没有考虑Sp对强度的影响,只是按施工操作要求的粘聚性确定Sp.在高强砼中,Sp对砼强度影响较大,试验表明,Sp减少,强度增加,Sp每减少1%,强度约增加1%;而Sp对粘聚性影响较小,原因是高强砼的 较小,水泥用量大,且掺入大量的掺合料.本身粘聚性很好.h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 2.3 骨料含量的影响h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 骨料含量对普通砼强度影响很小,而对高强砼影响较为显著,影响程度仅次于 .试验表明, 每减少0.01,强度增加3.5%~5%, 愈小,强度增长率越大.而 对强度的影响程度为 每减0.02,强度增加6.5%~9%.h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 2.4 单位用水量W0影响h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 普通砼中,当流动性一定时,用水量基本恒定,且当 一定时,用水量W0对强度影响甚少,因此,需水量主要按施工要求流动性确定;而在高强砼中,用水量的大小对强度影响较为显著,当 一定时,W0愈少,强度愈高.试验表明,其影响程度与骨料含量对强度影响一致,当每m3砼减少5 kg水时,强度增加3.5%~5%.但是,W0受到外加剂的种类及掺量、混合料的种类及掺量、坍落度损失要求制约.h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 2.5 外加剂的种类及用量的影响h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 在高性能砼中,一般都加有外加剂.常加的有高效减水剂和缓凝剂.减水剂主要用来提高砼流动性,其掺量的大小与减水剂种类、投放时间、水灰比、水泥与骨料种类、数量及环境温度等因素有关,很难予先确定准确的掺量.太小,减水效果不显著;太多,超过减水剂饱和点,不但流动性不再增加,砼还会产生离析,影响砼质量,同时还增加成本.缓凝剂也有类似情况,掺量适中,有利于减少坍落度损失,保证砼的泵送性能;掺量太小,作用不大;太多,凝结时间过长,影响后续施工操作,同时会使砼长时间疏松不硬,强度严重下降.h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 此外,水泥品种,掺合料的种类及掺量、骨料品种等对砼强度及工作性都有一定的影响.h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 3 普通砼配合比确定方法在高强砼中应用已显不足h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 从以上论述可见,由于材料品种繁多,性能各异,配合比中各参数对砼性能影响复杂.因此,高强砼中的各材料用量及各参数的取值很难象普通砼一样,予先确定一个具体值.因此,普通砼配合比确定方法在高强砼中应用已显不足.主要有以下几方面:h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 1)只考虑 对强度的影响,忽略其它参数或材料品种对强度的影响,得出的配比不经济.试验表明,同时考虑 、Sp、W0及骨料含量对强度的影响进行配制砼,可显著提高砼强度及节约水泥,节约水泥12%~20%.;h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 2)利用 ~f的线性关系进行强度调整,当 较小时,得出的配比不准确;h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 3)较难把砼强度,耐久性、工作性及经济性统一起来.在配合比设计时,虽然其也考虑这些内容,但它是孤立地考虑的,因而得出的配比不够合理;h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 4)未有考虑各材料的特性及各材料之间的相互影响;h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 5)较难适应多项要求的砼.如若同时要求砼满足强度、抗渗标号、坍落度、坍落度损失值、弹性模量及成本等目标,这种方法就显得无能为力.h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 4 应用“正交—综合评定法”确定高强砼配合比h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 4.1 正交—综合评定法:该方法是利用正交试验的原理按排试验,根据试验结果进行综合评定,找出满足各项工程要求的最佳配合比的方法.步骤及方法见4.3实例.h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 4.2 正交—综合评定法优点:h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 1) 在各材料及参数对砼性能的影响还不太清楚的情况下,它能很好地处理各材料、各参数之间的相互关系.它通过科学安排试验,利用其“整齐可比性”及“均衡搭配性”,通过分析试验结果,可得到优化的配合比.h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 2) 它能把砼强度、耐久性;工作性及经济性统一;适应多目标要求的砼;所得的配比技术先进,经济合理.h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 3) 通过试验数据的分析,可弄清各材料,各参数对砼强度、耐久性、工作性及经济性的影响趋势及其影响的主次关系,为施工管理、质量控制、成本管理提供依据.h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 4.3 实 例:h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 某工程,混凝土设计强度等级为C55,C60,采用泵送施工,坍落度要求150~180 mm.材料采用h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 p.o 525水泥,Dm=20 mm碎石,中河砂,FDN高效减水剂掺量为0.5%~1.1%,缓凝剂为糖蜜,掺量为h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 0.1%~0.3%.h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 1) 明确试验解决问题及考核指标h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 要解决的问题:提出满足施工要求,强度要求、耐久性要求及经济性要求的配合比.h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 考核指标:C55砼强度≥65 MPa,C60砼强度≥69 MPa,入泵坍落度S=150~180 mm,30 min后坍落度≥120 mm,成本愈低愈好.h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 2) 挑因素,选水平.选择的因素及因素水平如表1:h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
表1 试验因素水平表h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
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h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪水平h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| A(水泥用量)h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 (kg/m3)h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| B(单位用水量)h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 (kg/m3)h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| C(砂 率)h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 (%)h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| D(缓凝剂)h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 (%)h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 1h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 480h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 170h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 42h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 0h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 2h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 510h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 163h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 38h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 0.2h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 3h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 540h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 156h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 34h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 0.3h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| h% /Ã,Üàbbs.3c3t.comfHQuÌ仪h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪3)选择正交表:由于有4个因素,3种水平,故选择L9(34)正交表.h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 4) 试验安排:根据已选定的因素、因素水平及正交表,试验安排如表2. h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
表2 试验方案及结果表h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
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h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪试验号h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 因素h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 试验结果h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| Ah% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| Bh% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| Ch% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| Dh% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| FDNh% /Ã,Üàbbs.3c3t.comfHQuÌ仪 (%)h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| Sh% /Ã,Üàbbs.3c3t.comfHQuÌ仪 (mm)h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| △Sh% /Ã,Üàbbs.3c3t.comfHQuÌ仪 (mm)h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| fh% /Ã,Üàbbs.3c3t.comfHQuÌ仪 (MPa)h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 成本Wh% /Ã,Üàbbs.3c3t.comfHQuÌ仪 (元/m3)h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 综合h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 评分h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 名次h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 1h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 480h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 170h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 42h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 0h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 0.55h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 180h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 45h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 58.4h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 326.2h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 0h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| /h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 2h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 510h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 163h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 42h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 0.2h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 0.75h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 180h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 50h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 63.5h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 355.5h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 15h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 6h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 3h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 540h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 156h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 42h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 0.3h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 1.05h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 170h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 55h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 73.6h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 390.6h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 18h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 5h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 4h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 480h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 163h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 38h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 0.3h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 0.60h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 180h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 45h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 65.8h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 334.4h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 27h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 1h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 5h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 510h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 156h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 38h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 0h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 0.80h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 180h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 75h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 74.3h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 355.9h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 0h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| /h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 6h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 540h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 170h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 38h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 0.2h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 0.70h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 170h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 50h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 68.2h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 368.0h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 18h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 4h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 7h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 480h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 156h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 34h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 0.2h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 0.70h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 180h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 60h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 70.5h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 339.1h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 27h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 2h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 8h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 510h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 170h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 34h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 0.3h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 0.55h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 175h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 40h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 66.8h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 346.8h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 24h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 3h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 9h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 540h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 163h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 34h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 0h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 0.70h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 175h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 80h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 78.0h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 365.6h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 0h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| /h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| h% /Ã,Üàbbs.3c3t.comfHQuÌ仪h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪备注:FDN—高效减水剂;S—坍落度;△S—坍落度损失值;f—抗压强度;W—成本价.h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
5)试拌:按试验安排中各试验号的参数计算试拌用料.试拌时,高效减水剂用量以使流动性S=150~180 mm确定.并把试验结果填于表2.h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 6) 试验结果分析h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 ① 确定各因素对砼性能影响趋势及主次h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 各因素、因素水平对砼强度、坍落度损失值、成本影响如表3.表3数据是表2同一因素同一水平结果的平均值.通过对极差进行分析,可得出各因素对以上结果影响的主次,极差愈大,影响愈大.各因素对砼强度影响趋势大小为A>B>C>D,水泥用量、用水量,砂率大小对强度都有较大的影响;对坍落度损失值影响趋势大小为:D>B>A、C.缓凝剂掺量及用水量影响较显著;对成本的影响趋势大小为A>B>C>D,影响最大的为水泥用量.以上分析有利于施工管理,质量管理及成本管理.h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
表3 极差分析h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
|
h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪因素h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 强度/MPah% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 坍落度损失值/mmh% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 成本/元.m-3h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 1h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 2h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 3h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 极差h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| Δ 1h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| Δ 2h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| Δ 3h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 极差h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 1h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 2h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 3h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 极差h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| Ah% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 64.9h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 68.2h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 73.3h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 8.37h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 52h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 55h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 62h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 10h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 331.6h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 352.7h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 374.7h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 43.1h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| Bh% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 64.5h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 69.1h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 72.8h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 8.3h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 45h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 60h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 63h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 18h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 347h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 351.8h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 360.2h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 13.2h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| Ch% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 65.2h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 69.4h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 71.7h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 6.6h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 50h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 58h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 60h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 10h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 357.4h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 352.8h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 348.8h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 8.6h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| Dh% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 70.2h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 67.4h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 68.7h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 2.8h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 67h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 53h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 48h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 19h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 349.2h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 352.5h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 357.5h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| 8.1h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
| h% /Ã,Üàbbs.3c3t.comfHQuÌ仪h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 ② 确定最佳配合比h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 直观法:在目标数较少或较易判别优劣时可用此法.如本试验,以满足工作性要求,强度要求的条件下,成本低的为优.所以C55,C60配比分别可定为4#,7#试验结果.h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 综合评分法:当目标数较多或较难用直观法判别优劣时使用.步骤如下:第一,按各目标重要性程序不同,分别确定分值系数ki.如本试验,确定配比的原则为:在满足施工、强度要求的条件下,尽量节约材料,因此,强度,坍落度损失值、成本的分值系数ki分别取2,1,3.第二:评定各试验各目标得分:首先确定基本得分ai,再求该目标得分ki.ai.评定基本得分的方法为:若目标值不符合设计要求得0分;其余按优劣排列,分别得分为n,n-1…1.也可用跳跃式评分,以便把优劣拉开得分距离.第三:求各试验综合得分:把各试验各目标值得分相加.如7#试验,坍落度损失值、强度、成本的基本得分ai分别为3、5、6.目标值得分为:ai .ki=3×1,5×2,6×3,综合评分为31分.第四步:确定最佳配比:综合得分高为优.然后按综合分高低排名次,当综合分相同时,以最重要目标为优者为优.本试验排次见表二、由表二得C55,C66配比分别为4#及7#试验结果.h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 5 结束语h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 从以上论述可见,用正交综合评分法确定高强砼配合比,可避免试验的盲目性.它特别适合多目标要求的砼,能使砼满足工程各项要求,并取得一定的经济效益. h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
(责任编辑 张晓云)■h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
作者简介:卢进亮(1962-),男,广西玉林人,广西大学土木建筑工程学院高级工程师.h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 作者单位:卢进亮(广西大学土木建筑工程学院,广西 南宁 530004)h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 参考文献:h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 [1]卢进亮,张树辉.高性能混凝土配合比关键参数对强度的影响[J].广西大学学报(自然科学版),1998,(2):186.h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 [2]JGJ/T55-96.混凝土配合比设计规程[S].中华人民共和国行业标准.h% /Ã,Üàbbs.3c3t.comfHQuÌ仪 [3]陈肇元.高强混凝土及其应用[M].北京:清华大学出版社,1993.h% /Ã,Üàbbs.3c3t.comfHQuÌ仪
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