Overview of Sustainable Cementitious Composites Properties with Added Recycled Rubber

2015 ◽  
Vol 806 ◽  
pp. 119-126
Author(s):  
Dragica Jevtić ◽  
Dimitrije Zakić ◽  
Aleksandar Savić ◽  
Veis Šerifi

The paper is focused to the properties of cementitious composites such as: mortar, ordinary concrete and self-compacting concrete made by means of recycled rubber granulate as a partial replacement for commonly used aggregate. This paper, together with the results of authors' own experimental research on rubberized cementitious composites is presented in detail. The comprehensive conclusion suggests that this type of material can be successfully applied in many fields of engineering practice, thanks to its sustainability, elasticity and durability.


2015 ◽  
Vol 806 ◽  
pp. 127-134
Author(s):  
Dragica Jevtić ◽  
Dimitrije Zakić ◽  
Aleksandar Savić ◽  
Veis Šerifi

Applications of fly ash in building industry have very important and relevant problems of origin which are discussed in this paper. Authors have performed tests on mortar, plain concrete and Self Compacting Concrete (SCC) specimens. Experiments showed satisfactory results concerning possible application of fly ash as admixture for cementitious composites. Experimental research was conducted in the Laboratory for materials at the Faculty of Civil Engineering, University of Belgrade.



2021 ◽  
Vol 9 (2) ◽  
pp. 71-78
Author(s):  
O. M. A. Daoud ◽  
O. S. Mahgoub

Self-compacting concrete (SCC) is an innovative construction material in the construction industry. It is a highly fluid and stable concrete that flows under its own weight and fills completely the formwork. The SCC requires high powder content (mainly of cement) up to 600kg/ to achieve its properties. This will be problematic because increasing the cement content is not feasible, and may cause high cost and some other technical problems such as higher heat of hydration and higher drying shrinkage. This paper investigates the effect of limestone powder (LSP) on fresh and hardened properties of SCC due to the use of LSP as a partial cement replacement. For comparison, a control sample of concrete was prepared without LSP to compare it with the various samples containing different percentages of LSP as a partial replacement of cement. Four mixes with a constant amount of (superplasticizer, sand, coarse aggregate, and water) at various replacement levels of 0%, 10%, 20% and 30% from the cement weight were prepared. The experimental results show that the LSP can be effectively used as a partial cement replacement on SCC to reduced cost and enhanced the performance of SCC in fresh and hardened stages.  





2018 ◽  
Vol 149 ◽  
pp. 01026
Author(s):  
Taieb Fatima ◽  
Belas Nadia ◽  
Belaribi Omar ◽  
Belguesmia Khalil ◽  
Hadj Sadok Rachid

The use of SCC has a particular interest in terms of sustainable development. Indeed, their specific formulation leads to a greater volume of dough than for common concretes, thus, a larger quantity of cement. However, for economical, ecological and technical reasons, it is sought to limit their cement content [1]. It is therefore necessary to almost always use mineral additions as a partial replacement for cement because the technology of self-compacting concretes can consume large quantities of fines, in this case calcinated mud issued from dams dredging sediments that can give and/or ameliorate characteristics and performances of this type of concretes. Four SCCs had been formulated from the same composition where the only percentage of calcinated mud of Chorfa (west of Algeria) dam changed (0%, 10%, 20% and 30%). The effect of calcinated mud on characteristics at fresh state of SCC according to AFGC was quantified. Mechanical strengths and shrinkage deformation (total, autogenous, drying) were evaluated. The results show the possibility to make SCCs with different dosages of calcinated mud having strengths that can defy those of the control SCC. The analysis of free deformations indicates the beneficial impact of the mud by contributing to decrease the amplitudes of the shrinkage compared to those of the control SCC.





2019 ◽  
Vol 24 ◽  
pp. 25-36 ◽  
Author(s):  
Hamada Shoukry

Cement manufacturing, which is partially responsible for environmental and health risks as well as the greenhouse gas emissions, is a binder industry that needs energy and raw material. To decrease the needing, this study develops nano-modified eco-friendly cementitious composites including industrial solid wastes and/or by-products. For this purpose, ordinary Portland cement (OPC) was partially replaced with 70 wt% of fly ash (FA), Nano metakaolin (NMK) was incorporated at a rate of 2, 4, 6, 8, 10, 12 and 14 % as partial replacement by weight of FA to take advantage of the great role of nano materials in improving the mechanical and physical properties of cement based materials. Compressive strength, flexural strength, and capillary water absorption coefficient have been studied at 28 days of curing according to the international ASTM standards. Differential scanning calorimeter (DSC) was used to study the phase composition/decomposition. The microstructure characteristics of the hardened samples were investigated by scanning electron microscope (SEM) equipped with energy dispersive analytical x-ray unit (EDAX). The results revealed that the partial replacement of cement by 70% of FA has reduced both compressive and flexural strengths by about 45% in addition; the water absorption has been increased by about 175% as compared to the OPC. The replacement of FA by different amounts of NMK compensate for the loss in strength by about 75%. Furthermore, NMK has considerably improved the microstructure and reduced the water absorption by 86%. The study concluded that, it is possible to substitute 70% of the weight of the cement in the production of eco-friendly cementitious composites with improved mechanical performance attaining 88% of the corresponding performance of the hydrated OPC. The developed composites can be considered as green binders and recommended for various applications in construction industry.



Materials ◽  
2020 ◽  
Vol 13 (8) ◽  
pp. 1821 ◽  
Author(s):  
Robert Bušić ◽  
Mirta Benšić ◽  
Ivana Miličević ◽  
Kristina Strukar

The paper aims to investigate the influence of waste tire rubber and silica fume on the fresh and hardened properties of self-compacting concrete (SCC) and to design multivariate regression models for the prediction of the mechanical properties of self-compacting rubberized concrete (SCRC). For this purpose, 21 concrete mixtures were designed. Crumb rubber derived from end-of-life tires (grain size 0.5–3.5 mm) was replaced fine aggregate by 0%, 5%, 10%, 15%, 20%, 25%, and 30% of total aggregate volume. Silica fume was replaced cement by 0%, 5%, and 10% of the total cement mass. The optimal replacement level of both materials was investigated in relation to the values of the fresh properties and mechanical properties of self-compacting concrete. Tests on fresh and hardened self-compacting concrete were performed according to the relevant European standards. Furthermore, models for predicting the values of the compressive strength, modulus of elasticity, and flexural strength of SCRC were designed and verified with the experimental results of 12 other studies. According to the obtained results, mixtures with up to 15% of recycled rubber and 5% of silica fume, with 28 days compressive strength above 30 MPa, were found to be optimal mixtures for the potential future investigation of reinforced self-compacting rubberized concrete structural elements.



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