SEISMIC RETROFITTING OF EXTERIOR BEAM COLUMN JOINT USING FERROCEMENT

Abstract

Evidences from previous earthquakes have shown that failure in beam column joints may cause disastrous collapse of structures, especially for building without seismic provisions. To extend the life span of beam column joints, strengthening is required and this can be effectively achieved using ferrocement. Ferrocement is a composite material of weld mesh and woven mesh embedded in mortar with various volume fractions. It is bonded to the beam column joint for strengthening. In this study, eight full scale reinforced concrete exterior beam column joints, two control specimen and six specimens strengthened by the proposed method, were constructed and tested under cyclic loading. The displacement is increased monotonically using a hydraulic push and pull jack. The hysteretic curves of the specimen have been plotted. The energy dissipation capacity of retrofitted beam column joints with various ferrocement configurations has been compared. In addition, comparisons were made between experimental and analytical results of control specimen and ferrocement retrofitted specimen. The experimental result indicates that the proposed strengthening method is effective to enhance the ultimate loading capacity, stiffness and energy dissipation

Keywords

• Beam column joint, Ferrocement, retrofitting, Volume fraction, Energy dissipation, Cyclic loading, Hysteretic curves

References

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