Influence of the Type of Silica Fume on the Rheological and Mechanical Properties of Ultra-High Performance Concrete

2011 ◽  
Vol 488-489 ◽  
pp. 274-277 ◽  
Author(s):  
Kyung Taek Koh ◽  
Jung Jun Park ◽  
Su Tae Kang ◽  
Gum Sung Ryu
Keyword(s):  
Mechanical Properties ◽  
Surface Area ◽  
Silica Fume ◽  
High Performance ◽  
High Performance Concrete ◽  
Cementitious Materials ◽  
Ultra High Performance Concrete ◽  
Coarse Aggregates ◽  
Surface Areas ◽  
Compressive And Flexural Strengths

Ultra-high performance concrete (UHPC) is a new generation of concrete developed through microstructure enhancement techniques for cementitious materials. UHPC exhibits extremely high compressive and flexural strengths exceeding 180 and 30 MPa, respectively, and remarkable durability compared to normal concretes. The fabrication of UHPC requires very low W/B ratio reaching merely 0.2, the use of large quantities of fine binder and superplasticizer without coarse aggregates, and the incorporation of steel micro-fibers. This study investigates the effect of the type of silica fume on the rheological and mechanical properties of UHPC. The adopted silica fume presents various contents of SiO2 and surface areas. From the experimental results, UHPC using silica fume with 94% of SiO2 3% of ZrO2, and surface area of 80,000 g/cm3 shows better flowability than UHPC using silica fume with 98% of SiO2and surface area of 200,000 g/cm3 by lowering the viscosity of the cementitious composites without decreasing the compressive strength. Therefore, the fabrication cost of UHPC can be reduced by smaller dosage of superplasticizer when using silica fume with Zr content .

scholarly journals Production of Ultra-High-Performance Concrete with Low Energy Consumption and Carbon Footprint Using Supplementary Cementitious Materials Instead of Silica Fume: A Review

Energies ◽  
2021 ◽  
Vol 14 (24) ◽  
pp. 8291
Author(s):  
Mays A. Hamad ◽  
Mohammed Nasr ◽  
Ali Shubbar ◽  
Zainab Al-Khafaji ◽  
Zainab Al Masoodi ◽  
...  
Keyword(s):  
Energy Consumption ◽  
Silica Fume ◽  
High Performance ◽  
High Performance Concrete ◽  
Cementitious Materials ◽  
Supplementary Cementitious Materials ◽  
Ultra High Performance Concrete ◽  
Cement Production ◽  
Granulated Blast Furnace Slag ◽  
The Impact

The increase in cement production as a result of growing demand in the construction sector means an increase in energy consumption and CO2 emissions. These emissions are estimated at 7% of the global production of CO2. Ultra-high-performance concrete (UHPC) has excellent mechanical and durability characteristics. Nevertheless, it is costly and affects the environment due to its high amount of cement, which may reach 800–1000 kg/m3. In order to reduce the cement content, silica fume (SF) was utilized as a partial alternative to cement in the production of UHPC. Nevertheless, SF is very expensive. Therefore, the researchers investigated the use of supplementary cementitious materials cheaper than SF. Very limited review investigates addressed the impact of such materials on different properties of UHPC in comparison to that of SF. Thus, this study aims to summarize the effectiveness of using some common supplementary cementitious materials, including fly ashes (FA), ground granulated blast furnace slag (GGBS), metakaolin (MK) and rice husk ashes (RHA) in the manufacturing of UHPC, and comparing the performance of each material with that of SF. The comparison among these substances was also discussed. It has been found that RHA is considered a successful alternative to SF to produce UHPC with similar or even higher properties than SF. Moreover, FA, GGBS and MK can be utilized in combination with SF (as a partial substitute of SF) as a result of having less pozzolanic activity than SF.

Hydration, Shrinkages and Mechanical Properties of Ultra High Performance Concrete Containing Blast Furnace Slag and Algerian Dune Sand

2019 ◽  
Vol 42 ◽  
pp. 86-99
Author(s):  
Abdelfetah Zenati ◽  
Mahfoud Tahlaiti ◽  
Abdelhafid Khelidj ◽  
Mohamed Nadjib Oudjit
Keyword(s):  
Mechanical Properties ◽  
Blast Furnace ◽  
High Performance ◽  
High Performance Concrete ◽  
Current Trend ◽  
Cementitious Materials ◽  
Partial Substitution ◽  
Dune Sand ◽  
Ultra High Performance Concrete ◽  
Ecological Requirements

The new requirements for strength and durability have led to the development of Ultra High Performance concrete (UHPC) with outstanding mechanical properties and durability. However, the application of this type of concrete is exceptional, because of the high dosage of cement and the incorporation of expensive materials, such as silica fume (SF) whose dosage can reach 30% by weight of cement. This type of concrete is formulated on two bases: A fine granular skeleton (max diameter 630μm) and high cementitious materials content. The search for local materials to exploit them in the formulation of UHPC is the current trend. It is therefore necessary to control their effect on the behavior and evolution of cement hydration.The objective of this study is to highlight the influence of blast furnace (BFS) on hydration kinetics, linear endogenous shrinkage and chemical shrinkage at very early age (before 72h), drying shrinkage after hardening, as well as, the evolution of mechanical compressive strengths as a function of time. In addition, the exploitation of dune sand in the granular skeleton is an alternative to reduce the crushing energy and avoid microcracks possibly induced.The analysis of the results showed the interest of the use of the dune sand and the partial substitution of the cement by the BFS on the properties of the UHPCs in the fresh state and in the hardened state.In addition to the high performance achieved by UHPCs, their use, in Algeria, will meet both economic and ecological requirements given the abundance of very fine dune sand (southern Algeria) and complex blast furnace BFS of EL-Hadjar (Eastern Algeria).

Effect of the Type of Silica Fume and Filler on Mechanical Properties of Ultra High Performance Concrete

2018 ◽  
Vol 774 ◽  
pp. 349-354 ◽  
Author(s):  
Kyung Taek Koh ◽  
Seung Hun Park ◽  
Gum Sung Ryu ◽  
Gi Hong An ◽  
Byung Suk Kim
Keyword(s):  
Mechanical Properties ◽  
Silica Fume ◽  
High Performance ◽  
High Performance Concrete ◽  
Strength Loss ◽  
Limestone Powder ◽  
Cement Kiln ◽  
Ultra High Performance Concrete ◽  
Silica Powder ◽  
Kiln Dust

The large quantities of expensive materials such as steel fiber, silica fume, filler and superplasticizer required in the composition of Ultra-High Performance Concrete (UHPC) make its fabrication cost significantly higher than ordinary concrete. This study evaluates the effect of the type of silica fume and filler on mechanical properties of UHPC. The evaluation shows that the use of Zr silica powder instead of common silica fume improves significantly the fluidity of UHPC without loss of the strength and enables to reduce the amount of superplasticizer by maximum 70%. Moreover, the evaluation of the effect of the type and size of the filler reveals that modifying the size of the filler from 2 μm to 4 μm enhances the fluidity without strength loss and that the use of cement kiln dust (CKD) and limestone powder can achieve UHPC with compressive strength higher than 150 MPa. These results show that the use of the materials such as Zr silica powder, CKD and limestone powder can help to fabricate more economic UHPC.

scholarly journals Effect of FC3R on the properties of ultra-high-performance concrete with recycled glass

DYNA ◽  
2019 ◽  
Vol 86 (211) ◽  
pp. 84-93 ◽  
Author(s):  
Nancy Torres Castellanos ◽  
Jaime Antonio Fernández Gómez ◽  
Andres Mauricio Nuñez Lopez
Keyword(s):  
Silica Fume ◽  
High Performance ◽  
High Performance Concrete ◽  
Cementitious Materials ◽  
Supplementary Cementitious Materials ◽  
Partial Substitution ◽  
Ultra High Performance Concrete ◽  
Conventional Concrete ◽  
Recycled Glass ◽  
Cost Efficient

Ultra-high-performance concrete (UHPC) is the essential innovation in concrete research of the recent decades. However, because of the high contents of cement and silica fume used, the cost and environmental impact of UHPC is considerably higher than conventional concrete. The use of industrial byproducts as supplementary cementitious materials, in the case of recycled glass powder and fluid catalytic cracking catalyst residue (FCC), the partial substitution of cement and silica fume allows to create a more ecological and cost-efficient UHPC. This research presents a study to determine the possibility of partial substitution of cement by FCC in a previously optimized mixture of ultra-high-performance concrete with recycled glass. The results demonstrate that compressive strength values of 150 and 151 MPa without any heat treatment can be achieved, respectively, when replacing 11% and 15% of the cement with FCC, for a determined amount of water and superplasticizer, compared to 158 MPa obtained for the reference UHPC without any FCC content. The rheology of fresh UHPC is highly decreased by replacing cement particles with FCC.

scholarly journals Experimental Investigation and Prediction of Compressive Strength of Ultra-High Performance Concrete Containing Supplementary Cementitious Materials

2017 ◽  
Vol 2017 ◽  
pp. 1-8 ◽  
Author(s):  
Jisong Zhang ◽  
Yinghua Zhao ◽  
Haijiang Li
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
High Performance ◽  
High Performance Concrete ◽  
Cementitious Materials ◽  
Supplementary Cementitious Materials ◽  
Ann Model ◽  
Ultra High Performance Concrete ◽  
Superior Mechanical Properties ◽  
Normal Strength

Ultra-high performance concrete (UHPC) has superior mechanical properties and durability to normal strength concrete. However, the high amount of cement, high environmental impact, and initial cost are regarded as disadvantages, restricting its wider application. Incorporation of supplementary cementitious materials (SCMs) in UHPC is an effective way to reduce the amount of cement needed while contributing to the sustainability and cost. This paper investigates the mechanical properties and microstructure of UHPC containing fly ash (FA) and silica fume (SF) with the aim of contributing to this issue. The results indicate that, on the basis of 30% FA replacement, the incorporation of 10% and 20% SF showed equivalent or higher mechanical properties compared to the reference samples. The microstructure and pore volume of the UHPCs were also examined. Furthermore, to minimise the experimental workload of future studies, a prediction model is developed to predict the compressive strength of the UHPC using artificial neural networks (ANNs). The results indicate that the developed ANN model has high accuracy and can be used for the prediction of the compressive strength of UHPC with these SCMs.

scholarly journals Static mechanical properties and mechanism of C200 ultra-high performance concrete (UHPC) containing coarse aggregates

2020 ◽  
Vol 27 (1) ◽  
pp. 186-195 ◽  
Author(s):  
Lv Yujing ◽  
Zhang Wenhua ◽  
Wu Fan ◽  
Wu Peipei ◽  
Zeng Weizhao ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
High Performance ◽  
Coarse Aggregate ◽  
High Performance Concrete ◽  
Maximum Size ◽  
X Ray Diffraction ◽  
Ultra High Performance Concrete ◽  
Coarse Aggregates ◽  
Static Mechanical ◽  
Static Mechanical Properties

AbstractIn this paper, C200 ultra-high performance concrete (UHPC) containing coarse aggregate was prepared. Firstly, four different maximum size and three different type of coarse aggregate having significant differences in strength, surface texture, porosity and absorption were used to prepared the mixtures. Secondly, the effect of maximum size and type of coarse aggregate on the workability of the fresh UHPC and the mechanical behaviour of harden UHPC were investigated. Finally, a series micro-tests including mercury intrusion porosimetry (MIP), scanning electron microscope (SEM), X-ray diffraction (XRD) were conducted and the mechanism of the C200 UHPC were discussed.The results show that the type and maximum size of coarse aggregate have significant effect on the workability and mechanical properties of C200 UHPC. The basalt coarse aggregate with maximum size of 10mm can be used to prepare the C200 UHPC. The compressive strength and flexural strength of the C200 UHPC is 203MPa and 46MPa at 90 day, respectively. Besides, the micro-tests data show that the C200 UHPC has a compacted matrix and strong interface transition zone (ITZ), which make the aggregate potential strength fully used.

Sign in / Sign up

Export Citation Format

Share Document