Effect of Mineral Admixtures on Rheological Properties of Cement Paste

2014 ◽  
Vol 936 ◽  
pp. 1409-1413 ◽  
Author(s):  
Lin Chun Zhang ◽  
Ai Lian Zhang

The Marsh cone method and rotary viscosimeter are used to study the effect of mineral admixtures such as ultra-fine fly ash, ultra-fine slag, zeolite powder and silica fume on rheological properties of cement paste. Test results show that the optimal ratio of ultra-fine fly ash, ultra-fine slag, zeolite powder and silica fume are respectively 20%, 20%, 10% and 8%. And the optimized mix proportion is the composition of 8% silica fume and 12% slag. By using water reducing agent and mineral admixtures we could get the cement paste which has good liquidity and no bleeding.

2019 ◽  
Vol 7 (8) ◽  
pp. 245 ◽  
Author(s):  
Thi Chu ◽  
Jinhai Zheng ◽  
Da Chen ◽  
Thi Nguyen ◽  
Elsafi Elbashiry ◽  
...  

This novel study on cement paste material was conducted with the aim of keeping up with the rapid development of urban construction and contributing to the continuous improvement of building materials to overcome environmental issues. In this study, several kinds of industrial waste were used to enhance the properties of cement paste for application in a marine environment with a tropical climate, such as in Vietnam. This study focuses on evaluating the properties of cement paste containing cement replacement combining 0–30% fly ash, 0–10% silica fume, and plasticizer accounting for 0.3% and 0.4% of the binder by mass. Water demand, chloride ion and sulfate ion permeability, and microstructural properties of the cement paste were determined by thermogravimetric analysis (TGA), X-ray diffraction (XRD), and scanning electron microscope (SEM) and they were investigated after 28 and 56 days. The test results show that an optimum mixture could be obtained with the use of 20% fly ash, 10% silica fume (replacing Portland cement), and 0.4% plasticizer. The application of such materials to sea dikes affected by a tropical climate (characterized by heat, humidity, salty seawater, many big storms, large waves, and strong tides) was investigated for four years on the Vietnamese coast. The test results indicate that fly ash and silica fume can improve the corrosion and abrasion resistance of concrete in coastal areas with a tropical climate, such as in Vietnam.


Vestnik MGSU ◽  
2019 ◽  
pp. 102-117 ◽  
Author(s):  
Duc Vinh Quang Nguyen ◽  
Olga V. Aleksandrova ◽  
Yuriy M. Bazhenov

Introduction. This study focuses on the use of silica fume partially replacing cement with 0, 5, 7.5, 10, 12.5 and 30 % constant replacement of fly ash by weight of cement in concrete. Concrete is probably the most extensively used construction material in the world. But the conventional concrete is losing its uses with time and high-performance concrete (HPC) is taking that place. HPC has superior mechanical properties and durability to normal strength concrete. Because of, the microstructure of HPC is more homogeneous than that of normal concrete (NC) due to the physical and chemical contribution of the mineral admixtures as well as it is less porous due to reduced w/c ratio with the addition of a superplasticizer. The inclusion of additives helped in improving the properties of concrete mixes due to the additional reduction in porosity of cement paste and improving the particle packing in the interfacial transition zone (between cement paste and the aggregates).In this experimental investigation the behavior of HPC with silica fume and fly ash with and without quartz powder were studied. The water-binder ratio was kept 0.3 and 20 % quartz flour as partial replacement of fine aggregate for all cases. Materials and methods. Used materials in Vietnam, as follow, Sulfate-resisting Portland cement - PCSR40 (type V) of company Luks Cement (Vietnam) Limited was used in the work. Crushed granite of fraction 9.5…20 mm - as coarse aggregate, Natural sand from Huong river of 0.15…2.5 mm fraction with the fineness modulus of about 3.0 and quartz powder with an average particle size of 5…10 μm were used as fillers; Sika® Viscocrete®-151 is a superplasticizer based on a blend of 3rd generation PCE polymers was used as a plasticizing admixture. The flg ash from Pha Lai thermal power plant and Sika silica Sikacrete® PP1 (particle size < 0.1 μm) was used as a mineral active admixture. The study of strength and technological properties of high-performance concrete was performed by using standard methods. Results. Established by icate that, the workability and strength increase at a certain level and after that, they decline with further increase in the replacement level of silica fume is 12.5 %, on the basis of 30 % FA replacement, the incorporation of 10 % SF showed equivalent or higher mechanical properties and durability compared to the reference samples. Conclusions. HPC consists of mineral admixtures such as silica fume and fly ash use combine quartz powder and superplasticizer helped in improving the strength and durability of concrete mixes due to the additional reduction in porosity of cement paste and an improved interface between it and the aggregate. With 30 % fly ash is optimum dosage used to replacement of cement, incorporation 10 % SF (by weight) and combine of partial replacement of fine aggregate by 20 % quartz powder. On the other hand, a few mathematical equations can be used to derive the durability properties of concrete based on its compressive strength.


2010 ◽  
Vol 168-170 ◽  
pp. 281-285
Author(s):  
Ben Lin Xiao ◽  
Li Hua Li ◽  
Hui Ming Tang

The influence of mineral admixtures on mortar brittleness is analysed in this paper. Test results show that the mortar brittleness increases with the increasing of compressive strength and the passage of age. When the content of binding materials rises, the compressive strength also increases, but the brittleness decreases at the same time. The more the content of fly ash is, the more the brittleness falls. Silica fume added can not only enhance compressive strength but also reduce brittleness of the mortar. MgO added can cut down the brittleness, but can reduce the compressive strength a little at the same time, especially for early compressive strength.


2012 ◽  
Vol 578 ◽  
pp. 87-90 ◽  
Author(s):  
Hui Fang Zhang ◽  
Hong Liang Huang ◽  
Ying Fei Sun ◽  
Li Fang Zhang ◽  
Bao Xin Yao

In this paper, in order to discuss the compatibility of cement and different kinds of water reducers, three kinds of water reducers which were selected to use in the mix proportion of Jing Shi Special Passenger Line were chosen. Tests of cement paste and concrete of Portland cement (P∙O42.5) were carried out under different temperature, because this kind of cement is widely used in the current projects. Results show that polycarboxylic series water reducer, compared with naphthalene series water reducer, have properties of high compatibility, low mixing amount, high water-reducing rate and low slump loss of concrete. So it is more suitable to prepare concrete with fly ash and more beneficial to increase the strength of concrete.


2015 ◽  
Vol 1095 ◽  
pp. 248-253 ◽  
Author(s):  
Yuan Gang Wang ◽  
Peng Ma ◽  
Kai Jian Huang ◽  
Gao Qin Zhang ◽  
Ya Feng Hu

Fly ash, silica fume and ground steel slag are chosen to make up composite mineral admixtures. Through the orthogonal test, carbonization resistance property of High Performance Concrete (HPC) mixed with composite mineral admixtures is studied. Test results show that the carbonization resistance property of HPC can be improved with defined amount of composite mineral admixture mixed, in addition, the effect of ternary composite admixture of ground steel slag, fly ash and silica fume is more obvious than that of binary composite admixture.


2020 ◽  
Vol 9 (1) ◽  
pp. 2405-2411

This study investigates about the behaviour of high performance concrete produced with multi component composite cements. Here, the cement is partially replaced with certain mineral admixtures. The mineral admixture used in the study are fly ash, rice husk ash, silica fume and ground granulated blast furnace slag in various percentages up to 50%. The mix proportion for fly ash and rice husk ash are kept constant thought the study as 25% and 7.5% respectively. The Mechanical properties such as (Compressive strength, split tensile strength, flexural strength and modulus of elasticity), Durability tests (Acid test, Sorptivity), permeability test and Non Destructive test are performed on M40 grade concrete cube material property, cylinder and prism. The outcomes were analyzed with the controlled mix. The results shown that the M3 mix ( 50% cement, 25% fly ash, 7.5% RHA,7.5 % silica fume and 10 % GGBS) obtained optimum strength, durability and other properties when analyzed with the other mixes.


2008 ◽  
Vol 45 (6) ◽  
pp. 336-344 ◽  
Author(s):  
Jong-Taek Song ◽  
Hyo-Sang Park ◽  
Seung-Ho Byun ◽  
Dong-Woo Yoo

2011 ◽  
Vol 250-253 ◽  
pp. 1293-1296 ◽  
Author(s):  
Hong Bum Cho ◽  
Nam Yong Jee

This paper offers the model that can estimate the cementing efficiency of fly ash (k value) based on a mix proportion of concrete containing fly ash (FA). The prediction model was derived using various statistical analyses, based on a wide range of mix proportions and a number of strength test results of ready mixed concretes used in eight construction sites. The k value increases with increasing water-binder ratio. As the FA replacement ratios increase, the k value increases at FA replacement ratios of less than 15%, but decreases at ratios of 15% or more. The k values obtained from the cementing efficiency estimate model range from 0.1 to 2.1.


2018 ◽  
Vol 245 ◽  
pp. 03002 ◽  
Author(s):  
Petr Iubin ◽  
Lubov Zakrevskaya

Nowadays, the construction of cement composite using 3D printers is considered one of the most promising methods of automation of building processes. However, the compositions of cement composites have several disadvantages, such as high cost, short workability and etc. It has been suggested that clay soil as an additive will help to solve these problems partially. The aim of the work is development the cement compositions with clay soil, for use in 3D printers to construction. The composite consists of cement paste with clay soil and additives. To study printability of a composite the rheological properties in a fresh state were studied. The study of the rheological properties of composites was carried out using a flow table test for mortar. The key factor for determining the suitability of the composite for printing was accepted the diameter of the cone after shaking. The test results showed the possibility of replacing cement paste with clay soil up to 25% which leads to a reduction in the cost and an increase in printability with a slight decrease in the strength of the obtained material to 7%. Utilizing of soil from the construction site provides maximum economic efficiency of the material application.


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