Improvement of alignment in salt range area of motorway M-2 /

Abstract

functionality of the highway increases, the criteria of safety and geometric design become more significant. Lahore Islamabad Motorway (M-2) is one of the major motorways of Pakistan, connecting the Provincial and Federal Capitals. Being such an important highway, it has to fulfil certain geometric and safety criteria to serve the purpose efficiently. Despite of being a high class highway the Kalar Kahar Section of Motorway (Length Approx. 10 km) does not satisfy the required geometric design criteria and thus falls in one of the most dangerous roads to drive through. With the vertical grades going as high as 7% and the combinations of horizontal curves with the radius even lesser than 100 m, the speed of the vehicles reduce substantially, while heavy vehicles suffer the most. The main objective of this study is to find the prospect for improvement of bottle necks in Salt Range area of Motorway M-2 to avoid fatal accidents. The study has the focus to evaluate the existing alignment of the Kalar Kahar Section of M-2 and proposes the remedies at problematic locations. The study also has the scope to look for the alternative alignments through the Kalar Kahar Section and choose the best of those based upon the comparison of required geometric criteria and cost. The data has been collected and studied for the above set goals and the decision have been made based upon the analysis using relevant AASHTO guidelines. The modifications are recommended to improve the existing alignment. Four alternate alignments are also studied and based on comparison of several parameters, second alignment is recommended. The 31 km alignment is on the East of the existing alignment where it climbs the hill side between Hamat Nala and Saggar Nala through a series of wide hairpin bends and then takes a sharp turn towards the West to meet the existing alignment. This alignment satisfies the geometric design criteria and has enhanced safety of the existing alignment.