Structural Characteristics of HPDSP Concrete on Beam Column Joints

The seriously damaged structures during earthquakes show the need and importance of design of reinforced concrete structures with high ductility. Reinforced concrete beam-column joints have an important function in all structures. Under seismic excitation, the beam column joint region is subjected to horizontal and vertical shear forces whose magnitude is many times higher than the adjacent beam and column. Strength and ductility of structures depends mainly on proper detailing of the reinforcement in beamcolumn joints and the old structures were found ductility deficient. DSP materials are obtained by using high quantities of super plasticizers and high volumes of micro silica. In the case of High Performance Densified Small Particle Concrete (HPDSPC), since concrete is dense even at the micro-structure level, tensile strain would be much higher than that of the conventional SFRC, SIFCON & SIMCON. This in turn will improve cracking behaviour, ductility and energy absorption capacity of composites in addition to durability. The fine fibers used in our mix are 0.3mm diameter and 10 mm which can be easily placed with high percentage. These fibers easily transfer stresses and act as a composite concrete unit to take up extremely high loads with high compressive strength. HPDSPC placed in the beam column joints helps in safety of human life due to prolonged failure.

Authors:

• Sushil Kumar Swar
• Sanjay Kumar Sharma
• Hari Krishan Sharma
• Sushil Kumar

Keywords:

• High Performance Densified Small Particle Concrete (HPDSPC)
• Steel Fıber Reinforced Concrete (SFRC)
• Slurry Infiltrated Concrete (SIFCON)
• Slurry Infiltrated Mat Concrete (SIMCON).

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