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Properties and Thermal Stress Analysis of Blended Cement Self-Compacting Concrete  [PDF]
Benson Kipkemboi, Benson Kipkemboi, Shingo Miyazawa, Shingo Miyazawa
Open Journal of Civil Engineering (OJCE) , 2018, DOI: 10.4236/ojce.2018.82009
Abstract: Self-Compacting concrete is a concrete that is able to flow and consolidate under its own weight, completely fill the formwork even in the presence of dense reinforcement, whilst maintaining homogeneity and without the need for any additional compaction. Self-Compacting concrete is achieved by using high proportions of powder content and super?plasticizers. Due to this, pronounced thermal cracking is anticipated. Thermal cracking in concrete structures is of great concern. The objective of this research is to carry out experiments and investigate fresh and hardened properties of SCC developed using a blend of ordinary Portland cement and ground granulated blast furnace slag (GGBFS), to evaluate the applicability of Japan Concrete Institute (JCI) model?equations and?to find out any similarities and differences between Self-?Compacting concrete and normal vibrated concrete—Portland blast furnace slag concrete class B. Thermal stress analysis of the proposed Self-Compacting concrete and normal vibrated concretes were investigated by simulation using 3D FEM analysis. To carry out these objectives, concrete properties such as autogenous shrinkage, adiabatic temperature rise, drying shrinkage, modulus of elasticity, splitting tensile strength and compressive strength were determined through experiments. From experimental results, it was observed that except for the fresh properties, the hardened properties of Self-Compacting exhibit similar characteristics to those of normal vibrated concrete at almost similar water to binder ratios. It was also established that Self-Compacting concrete at W/B of 32% with a 50% replacement of ground granulated blast furnace slag has better thermal cracking resistance than SCC with 30% GGBFS replacement. It is also found that provided the relevant constants are derived from experimental data, JCI model equations can be applied successfully to evaluate hardened properties of Self-Compacting concrete.
A Self-Compacting Cement Paste Formulation using Mixture Design  [PDF]
A. Mebrouki,N. Belas,K. Bendani,N. Bouhamou
Journal of Applied Sciences , 2009,
Abstract: This study presents a self compacting cement paste formulation using Algerian local materials (binary cement consisting of natural pozzolana and limestone fillers). In this study, simple laboratory instruments were used i.e., mini-slump for spreading out diameters and Marsh cone for flow times measurements. A wide variation of combinations was used as preliminary tests to select pastes with acceptable properties and the use of the mixture plans method has shown that it is possible to define an experimental field inside which optimal measurements can be obtained. This field has been put mathematically into equation form conditioned by implicit constraints, defining zones of minimal shearing threshold and maximum viscosity and was then solved numerically. The optimization criterion was checked in addition to the interactivity between components utilizing the multiple combinations of proportioning of these materials. From results given by ternary diagrams and desirability functions, an optimal self-compacting cement paste mixture was defined. Experimental checking was performed to validate the obtained results.
Application of experimental plans method to formulate a self compacting cement paste
Mebrouki, A.,Belas, N.,Vi?a, J.,Argüelles, A.
Materiales de Construccion , 2010,
Abstract: The self-compacting concrete formulation means to elaborate a self-compacting cement paste to which will be injected aggregates. The purpose of this work is to find the composition of this cement paste containing local materials (pozzolanic cement, limestone fillers, superplasticizer and water) having self-compacting properties. The use of the experimental plans method shows that it is possible to delimit an experimental field bounded by the volumetric proportions of materials composing the paste. The field was transformed in equations form conditioned by implicit constraints, defining zones of minimal shearing threshold and maximum viscosity; numerical resolution submitted to the optimization criteria permitted to define the volumetric proportions of each mixing parameter contributing to the preparation of an optimal paste. After experimental checking to validate obtained results, conclusions are that, from results given by ternary diagrams and desirability’s functions, a composition of an optimal self-compacting cement pas was obtained. En este trabajo se estudia la constitución de una pasta autocompactante a base de materiales locales argelinos (cemento binario de base puzolánica natural de Beni Saf y filler calizo de cantera). La reología de la pasta se estudia en función de las dosificaciones de cemento, caliza, superplastificante y agua. La fluidez de las pastas así formadas se deducen de los ensayos de escurrimiento del mini cono y del tiempo de flujo en el cono de Marsh. Utilizando el dise o estadístico de mezclas, el número de ensayos se ha visto considerablemente reducido, el problema se transformó en ecuaciones y después se resolvió numéricamente. A partir de las curvas de los diagramas ternarios, uniendo las respuestas de escurrimiento y el tiempo de flujo de las pastas en función de las dosificaciones en constituyentes y estudiando las funciones de conveniencia para cada respuesta, se terminará por deducir una composición de pasta autocompactante.
Self Compacting Concrete under Local Conditions  [PDF]
Abderahmane Seddik, Ahmed Beroual, Abdesselam Zergua, Mohamed Nacer Guetteche
Open Journal of Civil Engineering (OJCE) , 2013, DOI: 10.4236/ojce.2013.32014
Abstract:

This paper presents the results of experimental investigations on mechanical properties of self compacting concrete made with local materials. The used materials were cement, aggregate and super plasticizer. Limestone powder, silica fume and blast furnace slag have been used as adjuvant in self compacting concrete (SCC). Self compacting concrete properties in fresh and hardened state are characterized and analyzed. The test results indicate the possibility to manufacture SCC with good rheological and mechanical properties using local materials.

Evaluation of Fresh and Hardened Properties of Self-Compacting Concrete  [PDF]
Oladipupo S. Olafusi, Adekunle P. Adewuyi, Abiodun I. Otunla, Adewale O. Babalola
Open Journal of Civil Engineering (OJCE) , 2015, DOI: 10.4236/ojce.2015.51001
Abstract: This paper compared the rheological properties and compressive strengths of self-compacting concrete (SCC) and conventional cement concrete. The flowability and segregation resistance of freshly mixed concrete specimens were examined by the V-funnel apparatus, while the characteristics of passing ability were investigated with the L-box apparatus. Cylindrical concrete specimens of 100 mm diameter × 200 mm length were investigated for compressive strength. The rheological properties of SCC are incomparable with those of the conventional concrete due to their diverse testing methods and characteristics of individual flow. The compressive strength results of hardened concrete showed that SCC gained strength slowly compared to the conventional cement concrete due to the presence of admixtures and its 28 days strength was lower than conventional cement concrete, but SCC eventually had potentials of higher strength beyond 90 days. Finally, the effect of water-cement ratio on the plastic properties of self-compacting concrete was quite negligible compared to conventional concrete.
Fiber Reinforced Self Compacting Concrete Using Domestic Waste Plastics as Fibres
R. Kandasamy,R. Murugesan
Journal of Engineering and Applied Sciences , 2012, DOI: 10.3923/jeasci.2012.405.410
Abstract: Fiber Reinforced Self Compacting Concrete (FRSCC) is a composite material consisting of cement based matrix with an ordered or random distribution of fiber which can be steel, nylon and polythene, etc., which offers several economical and technical benefits. In this study, domestic waste plastics (Polythene fibres) were used and the properties of concrete (viz., compressive strength, flexural strength, split tensile strength) are studied. The tests have been carried out as per EFNARC for fresh concrete and Indian Standard Code for hardened concrete.
Self-Compacting Concrete Incorporating Micro- and Acrylic Polymer  [PDF]
Ali Heidari,Marzieh Zabihi
Advances in Civil Engineering , 2014, DOI: 10.1155/2014/652362
Abstract: This study examined the effects of using acrylic polymer and micro-SiO2 in self-compacting concrete (SCC). Using these materials in SCC improves the characteristics of the concrete. Self-compacting samples with 1-2% of a polymer and 10% micro-SiO2 were made. In all cases, compressive strength, water absorption, and self-compacting tests were done. The results show that adding acrylic polymer and micro-SiO2 does not have a significant negative effect on the mechanical properties of self-compacting concrete. In addition using these materials leads to improving them. 1. Introduction Concrete is the world’s widely used construction material because of its properties. By increasing the use of engineers, SCC [1–6] was developed in Japan. One of the biggest differences between SCC and usual concrete is their incorporation of materials [7, 8]. SCC is considered to be a concrete that can be placed and compacted with no vibration and segregation [9–12]. Because cement, the most important part of the concrete, is very expensive, using SCC is very economical. Polymer concrete (PC) is a composite material which is formed by combining mineral aggregates or monomers [13]. Because of its high strength properties, rapid setting, and ability to resist a corrosive environment, PC is increasingly being used as an alternate to cement concrete in construction, highway pavements, waste water pipes, and other places. Polymers are mostly incorporated in the concrete mixed as emulsions of polymer in water (latexes), but dry polymer powders or liquid monomers or resins may be used [14]. The nature of microstructural modification and void filling and bridging of cracks that occurs when polymer formulations are incorporated in cement systems is such that polymers change the pore structure [15]. The polymer used in this paper is the polymerization product of acrylic acid. This polymer is based on acrylic resins. It has the ability to mix easily at any mortar and is consistent with a variety of acrylic paints. Micro-SiO2 had been used as an addition to SCC for 10 percent by weight of cement, although the normal proportion is 5 to 15 percent. With an addition of 10 percent, the potential exists for very strong, brittle concrete. High replacement rates will require the use of a high range water reducer. When it is used in concrete, it acts as a filler and as a cementitious material. The small microsilica particles fill spaces between cement particles and between the cement past matrix and aggregate particles. Microsilica also combines with calcium hydroxide to form additional calcium
Investigation of the existence of self compacting properties in high performance concrete through experimental tests  [cached]
Thalmus Magnoni Fenato,Berenice M. Toralles Carbonari,Francisco M. Leite,Heitor H. Yoshida
Semina : Ciências Exatas e Tecnológicas , 2007,
Abstract: The self compacting concrete is characterized by its capacity to flow inside the formwork filling it exclusively by the force of the gravity with adequate cohesion and viscosity in such a way that segregation does not occur. One of its characteristic is the presence of fines which provide the necessary cohesion,and grains with maximum diameter of 20 mm. This work presents some procedures and experimental methods that make it possible to evaluate self compacting properties of high performance concrete. First, a bibliographical review on the subject was carried out, and later, the equipment used for the accomplishment of the assays were manufactured, in order to verify the properties related to the self compacting concrete: cohesion, viscosity and segregation. As for the work, two concretes were produced with Portland ARI Cement, thick sand, stone powder, sand 0, superplasticizer made of ether-carboxilate chains that differentiate from each other for the presence of active silica in one of them and fly ash in the other. Based on the results, it was verified whether the high performance concrete had self compacting characteristics. In this case, both were considered positive. It was also analyzed the behavior of these concretes in their hardened state by means of the compressive strength test. The Self Compacting Concrete has many advantages such as: reduction in the number of employees, shorter construction period, the non-use of the vibrator and the filling of formworks with high density of… or of complex geometry.
Permeability Behavior of Self Compacting Concrete  [PDF]
Er. Sandeep Dhiman,,Arvind Dewangan,,Er. Lakhan Nagpal,,Er. Sumit Kumar
International Journal of Innovative Technology and Exploring Engineering , 2013,
Abstract: Self compacting concrete (SCC) is the new category of high performance concrete characterized by its ability to spread and self consolidate in the formwork exhibiting any significant separation of constituents. Elimination of vibration for compacting concrete during placing through the use of Self Compacting Concrete leads to substantial advantages related to better homogeneity, enhancement of working environment and improvement in the productivity by increasing the speed of construction. Understanding of this concrete flow property is of interest to many researchers. Flow properties of concrete at green stage are significantly governed by paste content, aggregate volume and admixture dosage. The flow properties of concrete is characterized in the fresh state by methods used for Self compacting concrete, such as slump-flow, V-funnel and L- box tests respectively. The number of trail mixtures are used and tests such as Slump Flow, V-Funnel, L-box etc. are conducted for their permissible limits, then the final proportions of ingredients and admixtures have been finalized for M30 , M 40 , M 50 and M 60 grade Concretes . In the present experimental investigation the main concentration is focused on permeability properties of self compacting concrete mixes.
INVESTIGATION OF THE CHEMICAL ADMIXTURE INFLUENCE ON THE PERFORMANCE OF SELF COMPACTING CONCRETE  [PDF]
Akhmad Suryadi,Qomariah,Sarosa R. M.
Academic Research International , 2012,
Abstract: A new formulation approach by using fines material supported by development of chemical admixture open the way to amazing progresses in concrete technology. The range of perfomances and characteristics that are covered by concrete have been expended in two waydirections from conventional concrete to self compacting concrete (SCC). In order to establish an admixture system which can fulfil the SCC requirements, the mixes contained either a small quantity of fly ash (20%) or none. The aim of the research is to evaluate and invertigate the use of chemical admixture in SCC mixes that influent the properties of hardening concrete.Three different chemical admixture were used in the research. Decreasing the water-cementpowder ratio may negatively influence the flowing ability of fresh concrete. Special attention must be paid to add of mineral admixtures, like fly ash are often used to modify the microstructure of the concrete matrix and to optimise the transition zone. The reduction ofwater-cement powder ratio in a decrease in porosity and increase the performance hardening concrete. In this research water to cement ratio around 0.28. The results shown that the lowest value of water-cement ratio the higher use of chemical admixture and increase thecompressive strength of SCC (MixCA3).
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