黏度改性剂对混凝土拌和物流变参数及匀质性能影响
|
摘要
通过ICAR流变仪、分层度测试仪和多功能力学试验机,研究了微珠黏度改性剂、复合黏度改性剂及其掺量对混凝土塑性黏度、屈服应力、分层度及力学性能的影响,揭示了微珠黏度改性剂和复合黏度改性剂对大流态新拌混凝土流变特性及匀质性的影响规律,并指出了适量掺入的优点及超量掺入的缺点,最后,结合北京市某工程泵送混凝土的应用情况,提出了可泵送、塑性黏度及分层度的关系。结果表明:掺入微珠黏度改性剂或复合黏度改性剂均能显著降低混凝土拌和物的塑性黏度和屈服应力,且随着它们掺量的增加,屈服应力、塑性黏度及分层度均呈现先减小后增大规律;同掺量下微珠黏度改性剂对混凝土拌和物浆体匀质性的破坏力大于复合黏度改性剂,即分层度大,然而降黏效果相反;当黏度改性剂掺量小于30%时,混凝土28 d抗压强度均大于空白样,但掺量大于30%时,28 d抗压强度均小于空白样。工程应用表明,长距离或高层泵送混凝土,并不是塑性黏度越低越好,而是存在一个合理范围,这个范围使得混凝土拌和物是一个触变性的匀质的黏性混合物,根据应用统计分析,可采用塑性黏度与分层度的交集表示混凝土可泵区间,其表达式为:[(0,塑性黏度)∩(0,分层度)]。
The effects of micro-bead viscosity modifier,compound viscosity modifier and its content on the plastic viscosity,yield stress,stratification and mechanical property of concrete are studied by ICAR rheometer,stratification tester and multifunctional mechanical testing machine.The effect regularity of microbead viscosity modifier and composite viscosity modifier on the rheological property and homogeneity of freshwater concrete are revealed,and the advantages of proper incorporation and disadvantages of overweight incorporation are pointed out.Finally,combining with the application of pumping concrete in a project in Beijing,the relationship among pump-ability,plastic viscosity and stratification is put forward.The result shows that(1) the incorporation of micro-bead viscosity modifier or composite viscosity modifier can significantly reduce the plastic viscosity and yield stress of the concrete mixture,and with the increase of their content,the yield stress,plastic viscosity and stratification of the concrete mixture reduces at first and thenincreases;(2) the destructive force of micro-bead viscosity modifier to the homogeneous performance of concrete mixture slurry is higher than that of adding same content of the compound viscosity modifier,that is,the degree of stratification is large,but the viscosity reduction effect is opposite;(3) when the content of viscosity modifier is less than 30%,the compressive strength of concrete is larger than that of blank,but when the content is more than 30%,the 28 d compressive strength is less than 28 days,and vise versa.Engineering applications show that for long-distance or high-level pumping of concrete,not the lower of plastic viscosity the better,but there is a reasonable range,which makes the concrete mixture a thixotropic homogeneous viscous mixture,and according to the applicative statistical analysis,the concrete can be pumped in the intersection of plastic viscosity and stratification,i.e.,(0,plastic viscosity) ∩(0,stratification) ].
The effects of micro-bead viscosity modifier,compound viscosity modifier and its content on the plastic viscosity,yield stress,stratification and mechanical property of concrete are studied by ICAR rheometer,stratification tester and multifunctional mechanical testing machine.The effect regularity of microbead viscosity modifier and composite viscosity modifier on the rheological property and homogeneity of freshwater concrete are revealed,and the advantages of proper incorporation and disadvantages of overweight incorporation are pointed out.Finally,combining with the application of pumping concrete in a project in Beijing,the relationship among pump-ability,plastic viscosity and stratification is put forward.The result shows that(1) the incorporation of micro-bead viscosity modifier or composite viscosity modifier can significantly reduce the plastic viscosity and yield stress of the concrete mixture,and with the increase of their content,the yield stress,plastic viscosity and stratification of the concrete mixture reduces at first and thenincreases;(2) the destructive force of micro-bead viscosity modifier to the homogeneous performance of concrete mixture slurry is higher than that of adding same content of the compound viscosity modifier,that is,the degree of stratification is large,but the viscosity reduction effect is opposite;(3) when the content of viscosity modifier is less than 30%,the compressive strength of concrete is larger than that of blank,but when the content is more than 30%,the 28 d compressive strength is less than 28 days,and vise versa.Engineering applications show that for long-distance or high-level pumping of concrete,not the lower of plastic viscosity the better,but there is a reasonable range,which makes the concrete mixture a thixotropic homogeneous viscous mixture,and according to the applicative statistical analysis,the concrete can be pumped in the intersection of plastic viscosity and stratification,i.e.,(0,plastic viscosity) ∩(0,stratification) ].
引文
[1]赵筠.混凝土泵送性能的影响因素与试验评价方法[J].江西建材,2014(12):6-32.ZHAO Jun.Influencing Factors and Test Evaluation Method of Concrete Pumping Performance[J].Jiangxi Building Materials,2014(12):6-32.
[2]WALLEVIK O H,WALLEVIK J E.Rheology as a Tool in Concrete Science:The Use of Rheographs and Workability Boxes[J].Cement and Concrete Research,2011,41(12):1279-1288.
[3]李路明,陈喜旺,张莉,等.超高层建筑混凝土泵送施工工艺探讨[J].建筑技术,2016,47(4):335-338.LI Lu-ming,CHEN Xi-wang,ZHANG Li,et al.Discussion on Concrete Pumping Construction Process of Super-high Building[J].Architecture Technology,2016,47(4):335-338.
[4]吴斌兴,陈宝钢,杨岳峰,等.高强高性能混凝土泵送粘阻力的现场检测[J].建设机械技术与管理,2011,12(1):153-156.WU Bin-xing,CHEN Bao-gang,YANG Yue-feng,et al.How to Detect the Viscous Resistance in Pumping the High Strength and High Performance Concrete in the Field[J].Construction Machinery Technology&Management,2011,12(1):153-156.
[5]余成行,刘敬宇,王磊.C60超高泵送混凝土的配制与施工[J].混凝土,2008(6):71-76.YU Cheng-hang,LIU Jing-yu,WANG Lei.Preparation and Construction of the C60 Concrete Pumped for Superhigh Building[J].Concrete,2008(6):71-76.
[6]陈连发,陈悦,陆洋,等.C60超高层泵送混凝土配合比设计[J].混凝土与水泥制品,2015(3):27-31.CHEN Lian-fa,CHEN Yue,LU Yang,et al.Mix Proportion Design on C60 Super-rise Pumping Concrete[J].China Concrete and Cement Products,2015(3):27-31.
[7]冯乃谦,李浩.纳米微珠的特性与应用[J].混凝土与水泥制品,2010(5):1-3.FENG Nai-qian,LI Hao.Characteristics and Applications of Nano Micro-bead(N-MB)[J].China Concrete and Cement Products,2010(5):1-3.
[8]高雅静,孙双鑫,陈科.微珠粉煤灰在超高性能混凝土中的应用[J].建筑技术,2014(1):26-29.GAO Ya-jing,SUN Shuang-xin,CHEN Ke.Application of Micro-bead Powdered Coal Ash in Ultra-high Performance Concrete[J].Architecture Technology,2014(1):26-29.
[9]王冲,蒲心诚.超细矿物掺合料对新拌混凝土的增塑减水机理分析[J].混凝土,2001(8):51-54.WANG Chong,PU Xin-cheng.Analysis of the Effect of Improving Fluidity and Reducing Water of Superfine Mineral Additive upon Fresh Concrete[J].Concrete,2001(8):51-54.
[10]黄法礼,李化建,易忠来,等.水粉比对不同类型自密实混凝土剪切变形行为的影响[J].建筑材料学报,2017,20(1):30-35.HUANG Fa-li,LI Hua-jian,YI Zhong-lai,et al.Effect of Water-powder Ratio on Shear Deformation Behavior of Self-compacting Concrete(SCC)[J].Journal of Building Materials,2017,20(1):30-35.
[11]ROUSSEL N,OVARLEZ G,GARRAULT S,et al.The Origins of Thixotropic of Fresh Cement Pastes[J].Cement and Concrete Research,2012,42(1):148-157.
[12]YAHIA A.Shear-thickening Behavior of High-perform an Cement Grout:Influencing Mix Design Parameters[J].Cement and Concrete Research,2011,41(3):230-235.
[13]HEIRMAN G,HENDRICKX R,VANDEWALLE L,et al.Integration Approach of the Couette Inverse Problem of Powder Type Self-compacting Concrete in a Wide-gap Concentric Cylinder Rheometer:Part II.Influence of Mineral Additions and Chemical Admixtures on the Shear Thickening Flow Behavior[J].Cement and Concrete Research,2009,39(3):171-181.
[14]FEYS D,VERHOEVEN D,SCHUTTER G D.Why is Fresh Self-compacting Concrete Shear Thickening[J],Cement and Concrete Research,2009,39(6):510-523.
[15]吴寅,关萍.影响高性能混凝土强度的因素研究[J].新型建筑材料,2005(7):1-5.WU Yin,GUAN Ping.Study on Factors of Influence on Strength of High Performance concrete[J].New Building Materials,2005(7):1-5.
[16]马先伟,张家科,刘剑辉.高性能水泥基材料内养护剂用高吸水树脂的研究进展[J].硅酸盐学报,2015,43(8):1099-1110.MA Xian-wei,ZHANG Jia-ke,LIU Jian-hui.Review on Superabsorbent Polymer as Internal Curing Agent of High Performance Cement-based Material[J].Journal of the Chinese Ceramic Society,2015,43(8):1099-1110.
[17]秦鸿根,高美荣,庞超明,等.SAP内养护剂改善膨胀混凝土性能及其机理研究[J].建筑材料学报,2011,13(4):394-399.QIN Hong-gen,GAO Mei-rong,PANG Chao-ming,et al.Research on Performance Improvement of Expansive Concrete with Internal Curing Agent SAP and Its Action Mechanism[J].Journal of Building Materials,2011,13(4):394-399.
[18]PAIVA H,ESTEVES L P,CACHIM P B,et al.Rheology of Hardened Properties of Single-Coat Render Mortar with Different Type of Water Retaining Agent[J].Construction&Building Materials,2009,23(2):1141-1146.
[19]孔祥明,张珍林.高吸水性树脂对高强混凝土浆体孔结构的影响[J].硅酸盐学报,2013,41(11):1474-1480.KONG Xiang-ming,ZHANG Zhen-lin.Effect of Superabsorbent Polymer on Pore Structure of Hardened Cement Paste in High-strength Concrete[J].Journal of the Chinese Ceramic Society,2013,41(11):1474-1480.
[2]WALLEVIK O H,WALLEVIK J E.Rheology as a Tool in Concrete Science:The Use of Rheographs and Workability Boxes[J].Cement and Concrete Research,2011,41(12):1279-1288.
[3]李路明,陈喜旺,张莉,等.超高层建筑混凝土泵送施工工艺探讨[J].建筑技术,2016,47(4):335-338.LI Lu-ming,CHEN Xi-wang,ZHANG Li,et al.Discussion on Concrete Pumping Construction Process of Super-high Building[J].Architecture Technology,2016,47(4):335-338.
[4]吴斌兴,陈宝钢,杨岳峰,等.高强高性能混凝土泵送粘阻力的现场检测[J].建设机械技术与管理,2011,12(1):153-156.WU Bin-xing,CHEN Bao-gang,YANG Yue-feng,et al.How to Detect the Viscous Resistance in Pumping the High Strength and High Performance Concrete in the Field[J].Construction Machinery Technology&Management,2011,12(1):153-156.
[5]余成行,刘敬宇,王磊.C60超高泵送混凝土的配制与施工[J].混凝土,2008(6):71-76.YU Cheng-hang,LIU Jing-yu,WANG Lei.Preparation and Construction of the C60 Concrete Pumped for Superhigh Building[J].Concrete,2008(6):71-76.
[6]陈连发,陈悦,陆洋,等.C60超高层泵送混凝土配合比设计[J].混凝土与水泥制品,2015(3):27-31.CHEN Lian-fa,CHEN Yue,LU Yang,et al.Mix Proportion Design on C60 Super-rise Pumping Concrete[J].China Concrete and Cement Products,2015(3):27-31.
[7]冯乃谦,李浩.纳米微珠的特性与应用[J].混凝土与水泥制品,2010(5):1-3.FENG Nai-qian,LI Hao.Characteristics and Applications of Nano Micro-bead(N-MB)[J].China Concrete and Cement Products,2010(5):1-3.
[8]高雅静,孙双鑫,陈科.微珠粉煤灰在超高性能混凝土中的应用[J].建筑技术,2014(1):26-29.GAO Ya-jing,SUN Shuang-xin,CHEN Ke.Application of Micro-bead Powdered Coal Ash in Ultra-high Performance Concrete[J].Architecture Technology,2014(1):26-29.
[9]王冲,蒲心诚.超细矿物掺合料对新拌混凝土的增塑减水机理分析[J].混凝土,2001(8):51-54.WANG Chong,PU Xin-cheng.Analysis of the Effect of Improving Fluidity and Reducing Water of Superfine Mineral Additive upon Fresh Concrete[J].Concrete,2001(8):51-54.
[10]黄法礼,李化建,易忠来,等.水粉比对不同类型自密实混凝土剪切变形行为的影响[J].建筑材料学报,2017,20(1):30-35.HUANG Fa-li,LI Hua-jian,YI Zhong-lai,et al.Effect of Water-powder Ratio on Shear Deformation Behavior of Self-compacting Concrete(SCC)[J].Journal of Building Materials,2017,20(1):30-35.
[11]ROUSSEL N,OVARLEZ G,GARRAULT S,et al.The Origins of Thixotropic of Fresh Cement Pastes[J].Cement and Concrete Research,2012,42(1):148-157.
[12]YAHIA A.Shear-thickening Behavior of High-perform an Cement Grout:Influencing Mix Design Parameters[J].Cement and Concrete Research,2011,41(3):230-235.
[13]HEIRMAN G,HENDRICKX R,VANDEWALLE L,et al.Integration Approach of the Couette Inverse Problem of Powder Type Self-compacting Concrete in a Wide-gap Concentric Cylinder Rheometer:Part II.Influence of Mineral Additions and Chemical Admixtures on the Shear Thickening Flow Behavior[J].Cement and Concrete Research,2009,39(3):171-181.
[14]FEYS D,VERHOEVEN D,SCHUTTER G D.Why is Fresh Self-compacting Concrete Shear Thickening[J],Cement and Concrete Research,2009,39(6):510-523.
[15]吴寅,关萍.影响高性能混凝土强度的因素研究[J].新型建筑材料,2005(7):1-5.WU Yin,GUAN Ping.Study on Factors of Influence on Strength of High Performance concrete[J].New Building Materials,2005(7):1-5.
[16]马先伟,张家科,刘剑辉.高性能水泥基材料内养护剂用高吸水树脂的研究进展[J].硅酸盐学报,2015,43(8):1099-1110.MA Xian-wei,ZHANG Jia-ke,LIU Jian-hui.Review on Superabsorbent Polymer as Internal Curing Agent of High Performance Cement-based Material[J].Journal of the Chinese Ceramic Society,2015,43(8):1099-1110.
[17]秦鸿根,高美荣,庞超明,等.SAP内养护剂改善膨胀混凝土性能及其机理研究[J].建筑材料学报,2011,13(4):394-399.QIN Hong-gen,GAO Mei-rong,PANG Chao-ming,et al.Research on Performance Improvement of Expansive Concrete with Internal Curing Agent SAP and Its Action Mechanism[J].Journal of Building Materials,2011,13(4):394-399.
[18]PAIVA H,ESTEVES L P,CACHIM P B,et al.Rheology of Hardened Properties of Single-Coat Render Mortar with Different Type of Water Retaining Agent[J].Construction&Building Materials,2009,23(2):1141-1146.
[19]孔祥明,张珍林.高吸水性树脂对高强混凝土浆体孔结构的影响[J].硅酸盐学报,2013,41(11):1474-1480.KONG Xiang-ming,ZHANG Zhen-lin.Effect of Superabsorbent Polymer on Pore Structure of Hardened Cement Paste in High-strength Concrete[J].Journal of the Chinese Ceramic Society,2013,41(11):1474-1480.