Karachi Northern Bypass Bridge Collapse

Karachi Northern Bypass Bridge Collapse It was a massive Design fault and not the error in the construction For the first time Let the pictures tell you the real untold story

To start with, just look at the length of this bridge span! Also, it is elevating in a sharp circle. No where in Pakistan is a bridge this heavy with such large span and such huge gap between pillars especially when the bridge is also elevating and circling. The design Consultants was ECIL. See the road signs in the picture below on the curve to warn the drivers of sharp bends.

When there is such huge gap between support pillars and such sharp bend and elevation, the structure would bend outwards and this is exactly what happened when this first girder was poured. Where would the entire load of this bridge come especially if it also starts to bend outwards? On the first pillar which was near where you can see the minibus on the left of the picture. You can’t see the pillar in this photo but what started to happen during construction is shown below.

Here you can clearly see that the first bridge span is tilted rightwards with uneven weight distribution on the pillars. The pillar on the left has almost no weight but the ones on the right are under extreme stress. You can clearly see the gap between the sub-structure and the span on the left. This fault came when this bridge was under construction. Work was delayed for over a year because of this design fault which was making it impossible to balance the weight of the bridge due to long span, elevation and sharp curve as we saw in first photo. The consultants kept on trying various methods to “repair” their design fault as you can see black carbon steel rods going through the underside of the bridge span and scaffoldings for the repair job. They tried hard to “lift” the span back to normal position but that did not work. That also increased thousands of tons of weight on the bridge span while the pillars were not designed for this extra weight. So instead of acknowledging that their design had fault, they “repaired” and gave a go ahead for the project. But the bridge was bending rightwards and became too heavy due to “repairs”.

But the inevitable bending of the bridge to the right continued increasing the pressure on one pillar on the extreme right of the above photo which finally gave way. Note that the first pillar on the left of the photo has almost no weight on it. But the pillar on the right was simply crushed as following photo shows.

This one pillar in above photo was taking the entire load of the bridge due to its bending right, increased weight of repairs, sharp curve, elevation and gap between bridge pillar sub-structures. Also, the designers recommended construction of speed breakers on the bridge to slow the traffic which further increased weight and pressure on this single pillar on the extreme edge where the bridge curved as you can see in the following photo now.

This photo gives you another very interesting but untold angle to the whole disaster. The design of the bridge was radically altered to go around this “Paracha textile mills” which is actually a Ghee factory ☺ !! The powerful and well connected owner of the Ghee mill had the Consultants and the city government change the design changed into a sharp curve and took a stay order from the court. The powerful city government also did not get the stay vacated nor put any pressure on the owner for the land and allowed a major and high risk design change. In reality, this huge bridge was not even required if this Textile/Ghee mill had been asked to give land for the national project. Now we come to the quality of construction as many people seem to believe that it was the contractor NLC who had to be blamed for the disaster.

The entire project Managers were also ECIL, the original designers. They checked the quality of construction at every stage and gave “OK” reports or “check reports” to the Contractors NLC for work to progress. NLC could not progress even a day of work without NOC from the Consultants. The quality and quantity of steel and concrete was tested and approved by the Consultants at every step. That is why when the faults developed; the ECIL accepted their mistakes as design faults, called in foreign consultants, and paid for the repair job. NLC was given a clean chit by the ECIL themselves and the NHA and their quality of work were never doubted throughout the project. So when the bridge collapsed due to bending of the bridge and pillar failure, not a single crack appeared on the span or the bridge structure itself. It was too robustly built as the pics below show.

Now you be the Judge - Was it the dangerous Design or the Construction which led to the collapse?