|
Total collapse of a portion of a 10-storey residential building in Ahmedabad.
Pancake collapse of 4-storey L-shaped RC framed school building in Ahmedabad.
Collapse of open ground storey RC frame residential building in Bhuj.
Numerous cases of dislodging of the weakly connected
overhead storage water tanks were observed in the entire earthquake affected
area. Picture shows dislodging of water tank appendages from atop unfinished
and finished RC frame buildings in Bhuj
Collapse of intermediate storey in a 6-storey RC frame commercial building at Bhuj.
Ground storey collapse of a 4-storey building with open ground storey at Bhuj.
Most RC buildings with open ground storeys that collapsed showed a very common practice of poor detailing; 6mm diameter lateral ties in the columns with 90o hooks and longitudinal spacing as large as 30cm. This did not provide the required confinement to the core concrete.
Collapse
of a portion of 6-storey residential building at Anjaar; the portion that
collapsed had an open ground storey.
Collapse of one-half of the 14-storey RC frame residential apartment building in Ahmedabad; the collapsed portion had a swimming pool on the roof, unlike the other half that is standing.
At Gandhidham, the right building had ground storey collapse. The two buildings shared a common wall.
Collapse of upper storey of buildings at Gandhidham. It is suspected that this may have been caused by inadequate lap lengths in the column reinforcement.
Collapse of ground storey of a two-storey RC frame building in Manfara village.
Collapse of the RC frame shelter at a bus stop near Pundi village.
One of the numerous RC frame multistory buildings at Ahmedabad that withstood the earthquake shaking with only minor cracking in the masonry infill walls.
The practice of floating columns in the upper storeys is very common in the cities in India. Close-up view shows shear cracks in the cantilever stub beam supporting a floating column in a 4-storey RC frame residential building in Ahmedabad.
These columns left for future extension show inadequate spacing of stirrups.
The area also offered examples of good RC detailing; residential building of Telecom department under construction at Bhuj.
Severe shear cracking sustained by the RC elevator core wall in a four-storey RC frame building in Ahmedabad.
Insufficient connection between the RC elevator core and rest of the building lead to the underutilization of the lateral strength and stiffness of the elevator core.
A
school in Gandhidham had both traditional construction as well as RC precast
buildings. In the precast
building, the roof panels were dislodged atop
the precast frame/wall system due to inadequate connections. In contrast,
the traditional constructions alongside did better.
Partial
collapse of the roof due to failure of ties between prestressed concrete
trusses of the warehouse at Kandla port. Close-up view shows the failure
of the connection welding between the tie and the truss.
Buildings with open ground storeys in the affected area were "propped" by structural steel sections and wooded posts as an immediate measure by the residents.
Improper
jacketing of columns that was practiced immediately after the earthquake
in numerous buildings at Ahmedabad. The new frame to be encased in concrete
rested on the finished ground floor and not carried to the foundation.
Similarly, it did not connect well with the beams above. Even the plaster
of beams and columns was not removed.
In some instances, a structural steel member was placed adjoining the RC damaged column. The old columns together with the adjoining steel member were jacketed with concrete. In this instance, the steel column was taken below the floor level but not extended till the foundation. |
