• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.89-94
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• 2003

In this research, the physical properties of self compacting concrete using ground granulated blast furnace slag and fly ash as a part of cement were investigated. Concrete using ground granulated blast furnace slag and fly ash was prepared with various ground granulated blast furnace slag(30-50 volume %) and fly ash(10-20 volume %) replacement for cement. The effect of each of the materals, which have effects on self compacting concrete made by the basic mix proportion used granulated blast furnace slag and fly ash after hardening, has been checked. The workability, flowing characteristics, resistance of segregation of materals, air content, and compressive strength of concrete using ground granulated blast furnace slag and fly ash were tested and the results were compared with those of ordinary portland cement concrete. In the experiment, we acquired satisfactory results at the point of flowing characteristics and strengths of concrete using ground granulated blast furnace and slag fly ash within the replacement ratio of 65%

• Coupled systems mechanics
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• v.8 no.4
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• pp.315-338
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• 2019

The numerical investigations have been carried out on reinforced concrete slab against blast loading to demonstrate the accuracy and effectiveness of the finite element based numerical models using commercial package ABAQUS. The response of reinforced concrete slab have been studied against the influence of weight of TNT, standoff distance, boundary conditions, influence of air blast and surface blast. The results thus obtained from simulations were compared with the experiments available in literature. The inelastic behavior of concrete and steel reinforcement bar has been incorporated through concrete damage plasticity model and Johnson-cook models available in ABAQUS were presented. The predicted results through numerical simulations of the present study were found in close agreement with the experimental results. The damage mechanism and stress response of target were assessed based on the intensity of deformations, impulse velocity, von-Mises stresses and damage index in concrete. The results indicate that the standoff distance has great influence on the survivability of RC slab against blast loading. It is concluded that the velocity of impulse wave was found to be decreased from 17 to 11 m/s when the mass of TNT is reduced from 12 to 6 kg. It is observed that the maximum stress in the concrete was found to be in the range of 15 to $20N/mm^2$ and is almost constant for given charge weight. The slab with two short edge discontinuous end condition was found better and it may be utilised in designing important structures. Also it is observed that the deflection in slab by air blast was found decreased by 60% as compared to surface blast.

• Explosives and Blasting
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• v.35 no.1
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• pp.1-17
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• 2017

The understanding of the pressure associated with air blast, which travels through air, and its effect on surface and underground structures is highly important. It is necessary to determine the pressure change with time and distance for a computer simulation of the explosion impact on a structure. From the previous studies, many empirical equations for estimating the parameters related to the pressure change. In this study, the empirical equations for predicting peak overpressure, duration of positive phase, impulse, minimum negative pressure, duration of negative pressure, arrival time, and decay constant were reviewed and analyzed. Also, the pressure changes predicted from the Kingery equation, which is the most commonly used, and from the other empirical equations were compared.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.10a
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• pp.579-584
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• 2002

In this research, the physical properties of self compacting concrete using ground granulated blast furnace slag as a part of cement were investigated. Concrete using ground granulated blast furnace slag was prepared with various ground granulated blast furnace slag replacement(20~80 volume %) for cement and the quantities of coarse aggregate in concrete were 50%, 55% and 60% of ratio of absolute volume of coarse aggregate. The workability, flowing characteristics, air content and compressive strength of concrete using ground granulated blast furnace slag were tested and the results were compared with those of ordinary portland cement concrete. In the experiment, we acquired satisfactory results at the point of flowing characteristics and strengths of concrete using ground granulated blast furnace slag within tile replacement ratio of 50% and the optimum quantity of coarse aggregate in concrete was found to be 50%~55% of ratio of absolute volume of coarse aggregate.

• International Journal of Concrete Structures and Materials
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• v.1 no.1
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• pp.19-28
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• 2007

A dynamic constitutive damage model for reinforced concrete (RC) structures and formulations of blast loading for contact or near-contact charges are considered and adapted from literatures. The model and the formulations are applied to the input parameters needed in commercial finite element method (FEM) codes which is validated by the laboratory blast tests of RC slabs from literature. The results indicate that the dynamic constitutive damage model based on the damage mechanics and the blast loading formulations work well. The framework on the dynamic constitutive damage model and the blast loading equations can therefore be used for the simulation of failure of bridge components in engineering applications.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.10a
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• pp.95-98
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• 1999

Recently, the use of the underwater concrete constructions with the antiwashout underwater concrete is increasing. In this study, we investigate the properties of pH, suspended solids, slump flow, box test, air contents of fresh antiwashout underwater concrete and the Unit weight, compressive strength of hardened antiwashout underwater concrete which Ground Granulated Blast Furnace Slag contents 0%, 10%, 20%, 30%, 50%, 60% at 7days and 28days age which is produced and cured in the water and sea water. As a result, Ground Granulated Blast Furnace Slag contents 30% was excellent.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.05a
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• pp.270-271
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• 2014

In this study, a replacement ratio of blast furnace slag coarse aggregate and a water binder ratio by an optimum combination of PHC file was investigated. As a results, the target strength 78.5MPa was altogether satisfied in a mix proportion 28-G100-SG0 and W/B ratio 26 %. The surface rupture was generated in 28-G0-SG100 combination after curing with the autoclave. According to the result of measuring the ingredient, the majority were the MgOH2 hydrate.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.10a
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• pp.383-388
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• 2000

In these days, there are out of natural sands in the construction field. It is required that development of substitute material for natural material. The blast-furnace slag could be a good alternative material in this situation. It can help resource recycling and the protection of environment. This study presents that the strength properties of mortar using air-cooled blast-furnace slag sand and water-cooled blast-furnace slag sand. The mixing design of this study have a few factors, three type of unit water, four types of W/C, five types of substitution rate. When air-cooled furnace slag sand used in mortar, as substitution rate is higher, 3, 7-days compression strength and flexural strength are going up. But, in case of water-cooled furnace slag sand mortar, strengths are going down.

• Journal of The Korean Society of Agricultural Engineers
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• v.55 no.3
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• pp.123-128
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• 2013

This study was performed to evaluate the slump flow, air content, setting time, compressive strength, adiabatic temperature rise and diffusion coefficient of chloride used ordinary portland cement, crushed coarse aggregate, crushed sand, river sand, fly ash, limestone powder, blast furnace slag powder and superplasticizer to find optimum mix design of low carbon green concrete for structures. The performances of low carbon green concrete used fly ash, limestone powder and blast furnace slag powder were remarkably improved. This fact is expected to have economical effects in the manufacture of low carbon green concrete for structures. Accordingly, the fly ash, limestone powder and blast furnace slag powder can be used for low carbon green concrete material.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.11a
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• pp.19-21
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• 2012

This paper was to investigate the effect of incinerator ash on engineering properties of the high volume blast furnace slag concrete through Mock-up test. Test results revealed that the use of recycled aggregates resulted in increase of slump compared with the OPC concrete. But, the use of recycled aggregates did not affect the results of air contents and chloride contents. The use of recycled aggregates showed shortening of setting time of high volume blast furnace slag concrete. When the recycled aggregate was used, delay in strength development at early age happened with high volume blast furnace slag concrete compared with that of OPC concrete.