Karachi Northern Bypass bridge collapse CASE STUDY Presented By: o ANUS AHMAD o SUNDAS RIAZ o SHAHRUKH NASEEM INTRODUCTION • The M10 is a motorway located in Sindh province. • however it is mostly referred to as the Karachi Northern Bypass. • It is 57 km long and consists of 4 lanes (2 lanes operational). • The construction work on the Bypass started in 2002 and was completed in 2007. What Happened???? • On September 1st, 2007, a bridge were collapsed. • 6 people were killed. • The bridge was constructed by the National Logistic Cell, a part of the Pakistan army. INTRESTING FACTS • The M10 is the second shortest motorway in Pakistan, the shortest being M3. • The M10 is actually a bypass diverging outbound traffic away from Karachi. • M10 is Pakistan's longest bypass REASON BEHIND THIS SNARIO Weather it was a massive design fault or error in construction ….. • As you can see there is such huge gap between support pillars and such sharp bend and elevation. • 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? • It is either design fault as well as construction error. ….. ….. • In the above picture you can clearly see that the first bridge span is tilted rightwards. • 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. ….. • The Consultant kept on trying to repair this design fault . At last black carbon steel rods use under the bridge but this plane doesn't work. • It also increased thousands of tons of weight on the bridge span while the pillars were not designed for this extra weight. • Instead of correcting the flaw Engineers build the bridge without any hesitation. …. • Due to the weight of carbon rods in bridge the right continued increasing the pressure on one pillar on the extreme right of the above photo. • Note that the first pillar on the left of photo has almost no weight on it. ….. This one pillar in above photo was taking the entire load of the bridge. Pakistan NAVY was digging the road under the bridge near the same pillar for water .So that’s situation too effects the pillar to break. Why Engineers make a decision to construct a sharp turn ??? 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 had the Consultants and the city government change the design into a sharp curve . In reality, this huge bridge was not even required if this Textile/Ghee mill had been asked to give land for the national project. Ethical Mistakes • 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. • The ECIL accepted their mistakes as design faults, called in foreign consultants, and paid for the repair job. Refrence • http://en.wikipedia.org/wiki/Karachi_Norther n_Bypass • http://www.scribd.com/doc/453338/Karachi- Northern-Bypass-Bridge-Collapse .
"Karachi Northern Bypass Case Study"