SP-173: Fifth CANMET/ACI International Conference on Superplasticizers and Other Chemical Admixtures in Concrete最新文献_第3页

Dispersion Mechanisms of Alite Stabilized by Superplasticizers Containing Polyethylene Oxide Graft Chains 含聚氧化物接枝链的高效减水剂稳定Alite的分散机理

SP-173: Fifth CANMET/ACI International Conference on Superplasticizers and Other Chemical Admixtures in Concrete Pub Date : 1997-09-01 DOI: 10.14359/6184

E. Sakai, M. Daimon

引用次数: 24

Influence of Superplasticizer Type on the Compresive Strength of Reactive Powder Mortars 高效减水剂种类对活性粉砂浆抗压强度的影响

SP-173: Fifth CANMET/ACI International Conference on Superplasticizers and Other Chemical Admixtures in Concrete Pub Date : 1997-09-01 DOI: 10.14359/6201

L. Coppola, R. Troli, A. Borsoi, P. Zaffaroni, M. Collepardi

{"title":"Influence of Superplasticizer Type on the Compresive Strength of Reactive Powder Mortars","authors":"L. Coppola, R. Troli, A. Borsoi, P. Zaffaroni, M. Collepardi","doi":"10.14359/6201","DOIUrl":"https://doi.org/10.14359/6201","url":null,"abstract":"Reactive powder mortar (RPM) mixtures cured at room temperature with different portland cement, silica fume and steel fibers were manufactured. The influence of the superplasticizer type on the ROM performance - in terms of w/c and compressive strength - was studied. The acrylic polymer (AP) admixture performed better than the naphthalene (SNF) or melamine (SMF) based superplasticizers in regard to lower water-cement ratio and higher compressive strength at ages after 3 days. The 1-day compressive strength of the RPM with the AP admixture was much lower than that of the corresponding mixtures with SNF or SMF with C3a-free portland cement with a low specific surface are was used. This was due to a strong retarding effect of the early hydration when this cement was used in combination with some silica fume types. With other portland cements, the retarding in the early hydration caused by AP did not occur and therefore the 1-day compressive strength was quite high. The 28-day compressive strength of RPM specimens, cured at room temperature, were strongly dependent on the type of cement, silica fume and superplasticizer. However, the highest values obtained in this investigation (160-180 Mpa) were lower than those reported by the inventors of RPM (170-230 Mpa).","PeriodicalId":21898,"journal":{"name":"SP-173: Fifth CANMET/ACI International Conference on Superplasticizers and Other Chemical Admixtures in Concrete","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1997-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75088489","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

Slump-Loss Improvement of Low-Heat High-Strength Concrete 低热高强混凝土坍落损失的改善

SP-173: Fifth CANMET/ACI International Conference on Superplasticizers and Other Chemical Admixtures in Concrete Pub Date : 1997-09-01 DOI: 10.14359/6189

K. Sakai, H. Watanabe, M. Kinoshita

引用次数: 0

Effects of a New Generation of Superplasticizers on the Properties of Fresh Concrete 新一代高效减水剂对新拌混凝土性能的影响

SP-173: Fifth CANMET/ACI International Conference on Superplasticizers and Other Chemical Admixtures in Concrete Pub Date : 1997-09-01 DOI: 10.14359/6203

J. Norberg, Peterson, P. Norberg, P. Billberg

引用次数: 17

Rheological Estimation of Flowing Mortar with a Superplasticizer 掺有高效减水剂的流动砂浆流变学研究

SP-173: Fifth CANMET/ACI International Conference on Superplasticizers and Other Chemical Admixtures in Concrete Pub Date : 1997-09-01 DOI: 10.14359/6195

S. Kakuta

{"title":"Rheological Estimation of Flowing Mortar with a Superplasticizer","authors":"S. Kakuta","doi":"10.14359/6195","DOIUrl":"https://doi.org/10.14359/6195","url":null,"abstract":"The fluidity of self compacting concrete is influenced by the fluidity of the composed mortar. This paper discusses the rheological estimation of the fluidity of high-flowing mortars with superplasticizers. The character of fine aggregates is considered the most effective factor on mortar fluidity. The applicability of the viscosity equation proposed by Mori and Ototake for condensed suspension liquids to highly-flowing mortar is discussed. Mortars were tested with different volume concentration of fine aggregate-suspended in highly-flowing paste. The result from rheological test using a Brookfield type viscometer indicated good agreement with the equation. Provided that the fluidity of the mortar behaves as a Bingham fluid, it can be estimated by plastic viscosity and yield value. These rheological tests were applied to two types of highly-flowing mortars composed of self compacting concrete mixtures ranging from 60 to 70 cm of slumping flow value. The effects of fine aggregate fluctuated with differences in water content, sand content and sand grading of the basic mortar. Test results showed that the character of the sand remarkably affects the fluidity of highly-flowing mortar.","PeriodicalId":21898,"journal":{"name":"SP-173: Fifth CANMET/ACI International Conference on Superplasticizers and Other Chemical Admixtures in Concrete","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1997-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82501168","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The Influence of Vinyl Polymers on the Characteristics of Polymer-Modified Mortars 乙烯基聚合物对聚合物改性砂浆性能的影响

SP-173: Fifth CANMET/ACI International Conference on Superplasticizers and Other Chemical Admixtures in Concrete Pub Date : 1997-09-01 DOI: 10.14359/6183

R. Arcozzi, G. Ferrari, L. Gini, G. Pistolesi

引用次数: 0

Use of High-Range Retarder-Plasticizer for Roller-Compacted Concrete of the Three Gorges Project in China 高缓凝增塑剂在三峡工程碾压混凝土中的应用

SP-173: Fifth CANMET/ACI International Conference on Superplasticizers and Other Chemical Admixtures in Concrete Pub Date : 1997-09-01 DOI: 10.14359/6215

Liang Wenquan, L. Huizhen, H. Zhen, Li Yajie

引用次数: 3

"Blending of Acrylic Superplasticizer with Napthalene, Melamine or Lignosulfoate-Based Polymers" 丙烯酸高效减水剂与萘、三聚氰胺或木质素磺酸基聚合物的共混

SP-173: Fifth CANMET/ACI International Conference on Superplasticizers and Other Chemical Admixtures in Concrete Pub Date : 1997-09-01 DOI: 10.14359/6185

L. Coppola, E. Erali, R. Troli, M. Collepardi

{"title":"\"Blending of Acrylic Superplasticizer with Napthalene, Melamine or Lignosulfoate-Based Polymers\"","authors":"L. Coppola, E. Erali, R. Troli, M. Collepardi","doi":"10.14359/6185","DOIUrl":"https://doi.org/10.14359/6185","url":null,"abstract":"Acrylic polymer (AP) performs better than other superplasticizers based on sulfonate-naphthalene-formaldehyde (SNF), sulfonated-melamine formaldehyde (SMF) or modified lignosulfonate (MLS). It is better than the other superplasticizers in terms of higher initial slump, at equal water-cement ratio (w/c), and lower rate of slump loss. AP, however, is a little more expensive than SMF and much more expensive than either NSF or MLS. Therefore, blending of AP with the other polymers could reduce the cost. The purpose of the present work was to study the influence of binary blended admixture (AP on one hand, and SNF, MSF or MLS on the other one) on the performance of superplasticized concretes in terms of slump, slump loss, specific gravity, air content and compressive strength at equal w/c. The data presented in this paper indicates that there is no practical advantage in blending AP with NSF or MSF. Moreover the combination of AP with NSF seems to be unreliable because produces an erratic reduction in the workability of the concrete mixture when about 75% of AP is replaced by NSF. On the other hand, a combination of AP with MLS appears to perform as well as the pure acrylic polymer in terms of workability, slump loss, air content and strength development, provided that the replacement of AP by MLS is not higher than 25%. Therefore, these blended AP-MLS superplasticizers appear to be very interesting because they are cheaper than the pure acrylic polymer at approximately equal performance.","PeriodicalId":21898,"journal":{"name":"SP-173: Fifth CANMET/ACI International Conference on Superplasticizers and Other Chemical Admixtures in Concrete","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1997-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84497316","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

Influence of Characteristics of Sulfonic Acid-Based Admixture on Interactive Force Between Cement Particles and Fluidity of Cement Paste 磺酸基外加剂特性对水泥颗粒间相互作用力及水泥浆体流动性的影响

SP-173: Fifth CANMET/ACI International Conference on Superplasticizers and Other Chemical Admixtures in Concrete Pub Date : 1997-09-01 DOI: 10.14359/6176

H. Uchikawa, S. Hanehara

{"title":"Influence of Characteristics of Sulfonic Acid-Based Admixture on Interactive Force Between Cement Particles and Fluidity of Cement Paste","authors":"H. Uchikawa, S. Hanehara","doi":"10.14359/6176","DOIUrl":"https://doi.org/10.14359/6176","url":null,"abstract":"The relationship among the amounts of adsorption admixtures to cement particles, the interactive force between cement particles and the zeta potential of cement particle and fluidity of cement paste prepared at the W/C ratio of 0.3 with lignin sulfonic acid-based admixture (LS), aminobenzene sulfonic acid-based admixture (AS) or melmine sulfonic acid-based admixture (MS) was studied in this paper, aiming at obtaining the basic data for elucidating the effects of the characters of sulfonic acid-based organic admixtures on the fluidity of concrete. The amount of adsorption of the sulfonic acid-based admixture by cement particles are logarithmically related to the molecular weight of the admixtures. The lower the molecular weight, the more the amount adsorbed are. The zeta potential of cement particle in cement paste depends upon the content of sulfonate group in the admixture and the adsorption state of admixture. The interactive force between cement particles are linearly related to the fluidity of cement paste. The steric repulsive force considerably contributes to the dispersion of particles even in the addition of sulfonic acid-based admixture which has been considered so far to disperse the particles mainly by the electrostatic repulsive factor. The steric repulsive force is related to the molecular weight of the sulfonic acid-based admixture except AS. The rate of contribution of electrostatic repulsive force to the total repulsive force accounting for the interactive force correlates with the content of sulfonate group in the admixture. The reason why the action of AS is different from those other mixtures is probably because the adsorption state of AS is different than those from others.","PeriodicalId":21898,"journal":{"name":"SP-173: Fifth CANMET/ACI International Conference on Superplasticizers and Other Chemical Admixtures in Concrete","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1997-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81601368","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

Pore Solution Composition and Electrochemical Behavior of Steel Bars in Mortars with Nitrite Corrosion Inhibitors 添加亚硝酸盐缓蚀剂砂浆中钢筋的孔隙溶液组成及电化学行为

SP-173: Fifth CANMET/ACI International Conference on Superplasticizers and Other Chemical Admixtures in Concrete Pub Date : 1997-09-01 DOI: 10.14359/6177

M. Kawamura, S. Tanikawa, R. Swamy, H. Koto

{"title":"Pore Solution Composition and Electrochemical Behavior of Steel Bars in Mortars with Nitrite Corrosion Inhibitors","authors":"M. Kawamura, S. Tanikawa, R. Swamy, H. Koto","doi":"10.14359/6177","DOIUrl":"https://doi.org/10.14359/6177","url":null,"abstract":"The effectiveness of CA(NO2)2 and NaNO2 as corrosion inhibitors has been confirmed. However, the behavior of NO2-ion and its stability in the pore solution in concrete containing the inhibitors is a matter of concern for their effective use as a corrosion-inhibiting admixture. Furthermore, it may be important from the viewpoint of the corrosion of reinforcement in concretes contaminated with CI-ion to examine the behavior of No2-ions in relation to CI-ion concentration in the pore solution in concrete. In this study, the analyses of pore solutions expressed from NaCI containing-mortars with and without the inhibitors were carried out to elucidate effects of the inhibitors on the chloride binding capacity of mortars. Simultaneously, the corrosion rate of steel bars embedded in the mortars was monitored by measurements of the potential and polarization resistance. The NO2-ion concentrations in the pore solutions in NaCI-containing mortars treated with 1% Ca(NO2)2 by mass of cement were lower than those in the corresponding mortars with NaNO2. The addition of NaNO2 raised the OH-ion concentration slightly, but the OH-ion concentration was somewhat reduced in the mortars with Ca(NO2)2. The combined addition of NaCI and NaNO2, on the other hand, greatly raised the OH-ion concentration. However, the CI- /NO2- ratios in the pore solutions in mortars containing Ca(N)2)2 were slightly lower than in mortars containing NaNO2 because of the dissipation of greater amounts of CI-ions from the pore solutions in the former than in the latter.","PeriodicalId":21898,"journal":{"name":"SP-173: Fifth CANMET/ACI International Conference on Superplasticizers and Other Chemical Admixtures in Concrete","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1997-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78514942","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2