| Summary: | Colum reinforcement is esential in a structure. When a column is weak, it will
cause total failure to the structure. This study examined the behavior of column
reinforced with mortar jacketing method and wire netting. The objective of this study
was to identify the contribution of the reinforcement to the shear strength and
column ductility.
Four column specimens were made. They consistd of one original column (as
comparison) in square shape of 150 x 150 mm, and 700 mm height and foundation
plate in 1200 x 700 mm with 250 mm thickness and three specimens in same
dimension and strengthened by mortar jacketing to become column with square
shape of 190 x 190 and 730 mm height. Longitudinal reinforcement and wire nett in
1.7 mm diameter and consistend of small squares of 25 mm x 25 mm with 1 layer
strengthening (KP-1). Two layers (KP-2), and 3 layers, (KP-3) were used as the
mortar jacketing. Sika Grout 215 New was used as the filler. Loading type used was
constant axial and cyclic lateral load to simulate earthquake by using the
displacement control method.
Results of this study show that in KP-1, KP-2 and KP-3 reinforced column,
their latral load capacities increase by 192,740%, 204,718%, 228,856%,
respectively, than the average original column (KA-1). Addition of wire nett for KP-
1, KP-2, and KP-3 show general increase of displacement at a maximum lateral load
in comparison to the original column (KA-1). Drift ratio at maximum load at KA-1
was 2.096%. As for KP-1 and KP-3, the maximum load were 2.104 %, 2,026 and
2,124%, respectively. The stiffness values obtained from the test for KA-1, KP-1,
KP-2 and KP-3 were 3.92 KN/mm, 10,0854 KN/mm,11,6649% and 11,8738 KN/mm,
respectively. Ductility factor (μ ) of KA-1, KP-1, KP-2 and KP-3 were 2,988, 1,458,
1,259, and 1,391, respectively. Thus, more wire nett show lower ductility. Based on
the results and the regulation of ACI 374.1-05.200, the reinforced column could be
used for structures with maximum R (response modification factor) of 6.
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