o Self Compacting Concrete was first developed in Japan in the year o Prof . ronaldweinland.infoa of University of Tokyo, Japan; is mainly responsible for initiating. concrete. ´Mix design principles. ´Testing self-compacting concrete By developing concrete that self- compacting, he .. ronaldweinland.info 2. Specification and Guidelines for. Self-Compacting Concrete. February EFNARC, Association House, 99 West Street, Farnham, Surrey GU9 7EN, UK.
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Self-compacting concrete was first developed in to achieve durable concrete structures. tion work is the employment of self-compacting con- crete, which. PDF | Self-compacting concrete is a fluid mixture suitable for placing in structures with congested reinforcement without vibration. Self-compacting concrete. PDF | SELF COMPACTING CONCRETE WITH TESTS | ResearchGate, the professional network for scientists.
It is interesting to note that even though the water to binder ratio for the mix NAC35 mix was 0.
Figure 3. Compressive strength development with age for con- 3.
The results showed that and the water to binder ratio of 0. The differ- For the high strength concrete with low cement ences in strength values between these two mixes at content NAC35 , the day compressive strength all ages are due to the combined effects on the dif- was However for con- placement levels.
Figure 2 also shows that the con- crete with high cement content, day strength crete with ultra-fine slag showed continuous dropped from In addition, tensile strength the slag related to its high fineness.
Therefore, it can gregate, the migration coefficient was increased to be said that high strength concrete strength of with 5. This is the recycled concrete aggregates is responsible for due to the pore-size refinement resulting from the these reductions in the mechanical properties.
Due to pozzolanic reaction of the slag.
Tensile strength, modulus of elasticity and chloride aggregate containing relatively soft attached mortar migration for slag concrete to the natural aggregate, both drying shrinkage and Property NAC NAC RAC RAC creep of high strength concrete with recycled aggre- 35 75 35 75 Comp.
Tensile strength MPa 5. Further research is needed to establish the Elastic modulus GPa Self-compacting concrete with ultra-fine slag is less sensitive to the variation in the water to binder ratio.
Use of recycled concrete coarse aggregate pro- duced reduction in strengths and elastic modulus and increased the chloride migration coefficient.
With due consideration to the negative effects of using recycled concrete aggregates, high strength self-compacting recycled concrete can be pro- duced for sustainable concrete construction. Effect of ultra-fine slag on the fresh and hardened properties of ultra-high strength concrete, Advanc- es in Concrete: An Asian Perspective, Eds.
Gettu et. Domingo, A.
European guidelines for self- compacting concrete. Ghazi, F. New method for propor- tioning self-consolidating concrete on compressive strength requirement, ACI Materials Journal Goldman, A. The influence of microfiller on enhancement of concrete strength. Additionally, the SCC showed fracture energy values that were lower than the fracture energy values for the corresponding CVC. The only exception was S50d12C, which presented a fracture energy that was equivalent to the fracture energy of V50d12C.
The results listed in Table [ 4] show that the values for the CVC are slightly above the values suggested by recommendation TC FMT, considering the dispersion of the linear regression slope wA and the coefficient of variation that intercepts the regression line wC [ 5 ].
The relative dispersion band width m was satisfactory. For the SCC, the values of the dispersion coefficients wA , wC and m were lower than the values of the dispersion coefficients suggested by the methodology, with the exception of the coefficients for concrete S50d20F, whose values were higher than the recommended values. This result can be explained by the use of a larger amount of fine particles in the SCC.
Fines tend to improve the properties of the interface between the aggregate and the binder and generate a greater aggregate grain fracture during crack propagation Figure [ 4]. Figure [ 4] shows the fracture surface of a V30d20C beam upper part of the photo compared with the fracture surface of an S30d20C beam lower part of the photo. As shown in Figure [ 4] , V30d20C has a rougher fracture surface that is primarily characterized by crack propagation across the cement paste-aggregate interface, which contours the aggregate surface.
In S30d20C, the fracture surface is smoother, in which a high incidence of aggregate grain fractures during crack propagation is observed. The greater aggregate grain fracture in SCC is primarily attributed to the strengthening of the transition zone between the aggregate and the cement paste, considering the larger amount of fines in these concrete. Note that the amount of fines can be directly related to the size of the FPZ and that the particle size distribution and the amount of fines in the concrete influences the fracture energy values.
The influence of particle size distribution and maximum aggregate diameter on FPZ length is analyzed by the size effect graph Figure [ 5]. The strengths of the concrete structures decrease with an increase in the size of the structures.
In general, structures tend to be more brittle as they increase in size, which is described as the size effect and can be explained by fracture mechanics.
As shown in Figure [ 5] , note the decline in nominal strength with an increase in the size of the specimen. The same figure also shows a band that corresponds to nonlinear fracture mechanics NLFM. As shown in Figure [ 5] , the failure stress for the smaller specimens is proportional to the failure stress that is provided by the criteria given by the theory of strength of materials.
In this case, a classical strength criterion may be applied to analyze the behaviors of these specimens.
The horizontal line in Figure [ 5] represents a classical strength criterion that is based on stress. Large structures intensely show the size effect, i. In the region of the intersection between these two lines, that is, the intersection between the classical strength criterion and the criterion based on LEFM, a transition zone exists where NLFM should be adopted.
The results of the majority of the tests performed with the concrete specimens are located in this transition zone Figure [ 5]. When S30d12F and V30d12F as well as S50d20F and V50d20F are compared, the addition of fines to the SCC improved the properties of the interface between the aggregate and the paste for this concrete, which rendered them more brittle.
The comparison between S50d12C and S50d20F reveals that the reduced particle size distribution, which is associated with increased maximum diameter, produced a The addition of fine particles to concrete improves the properties of the interface and increases its strength but causes it to become more brittle.
A higher incidence of aggregate grain fractures was observed during crack propagation; this observation was noted when comparing the SCCs with the CVCs. The methodology to determine the fracture parameters of CVC and SCC according to the RILEM TC FMT specification, which is based on the size effect method, was adequate for routine use to characterize the concrete based on fracture mechanics because it is based on a simple load application system that only requires that the maximum load be achieved during the test, without the use of a servo-controlled machine.
Thus, this methodology is perfectly viable for the characterization of concrete in a reasonably well-equipped laboratory with respect to aspects of softening and structural brittleness, based on estimates of the following properties: This brittle behavior is related to the improvement of the interface properties due to the use of a finer particle size distribution in the SCC compared with the CVC.
The use of artificial sand in the preparation of the SCC to increase the amount of fines was very effective in reducing the cost of production of these two types of concrete. The CVC and SCC exhibited similar behavior, considering the compressive strength, which was significantly influenced by the particle size distribution. The use of a finer particle size caused an increase in the compressive strength values.
The moduli of elasticity for the SCC were slightly lower than the moduli of elasticity for the reference CVC, considering the same compressive strength level. However, this slight reduction in the modulus of elasticity can be compensated by increasing the productivity of the SCC and improving the construction process, as evidenced by lower coefficient of variation values for the SCC compared to the CVC.
Mech-ASCE, As resistance of the mixes. All rights reserved by www. Mix Specifications 7-days days SCC Results of compressive strength Adichunchanagiri Shikshana Trust. Sri Sri Gunanatha From the above table it is observed that Swamiji, Secretary, Chikmagalur branch, Principal and compressive strength at days is more than 7-days.
SCC 2. Table 5: Further marginal gain in strength corresponding developments, Issue 2, Vol. Shanthi, , increase in percentage of the silica fume.
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