Padma Multipurpose Bridge Project

6.7 Preferred Options34. Weighted score of both the options for the main bridge is presented in Table 6-6. Weightedsummation of score for composite steel truss bridge is higher than the extradosed concrete bridge.Hence, the steel truss bridge is considered the preferred scheme for the main bridge.Table 6-6: Weighted Score of Main Bridge OptionsScoreWeighted ScoreParameter Weightage ExtradosedConcrete BridgeSteel TrussBridgeExtradosedConcrete BridgeSteel TrussBridgeTechnical Robustness 25 2 4 50 100Constructability 20 2 4 40 80Maintenance 10 4 2 40 20Cost 20 2 3 40 60Social & Resettlement 5 3 2 15 10Environment 10 3 2 30 20Proven Previous Use 10 2 5 20 50Total 100 235 34035. Weighted score of both the options for the transition structures is presented in Table 6-7. OptionH1 has the higher total weighted score. Option H1 was thus selected as the preferred transitionstructure.Table 6-7: Weighted Score of Transition Structure OptionsParameter WeightageScoreWeighted ScoreOption H1 Option H2 Option H1 Option H2Technical Robustness 20 3 2 60 40Constructability 15 4 3 60 45Maintenance 5 2 3 10 15Cost 10 3 2 30 20Social & Resettlement 20 2 4 40 80Environment 30 4 2 120 60Total 100 320 26036. Weighted score of all RTW options are presented in Table 6-8. Scores for RTW options aretaken from ‘RTW Final Scheme Design Report’ and were calculated in the scale of 0 to 100.Alternative 1, revetment along bank has the highest total weighted score and hence is considered asthe preferred option for RTW.Table 6-8: Weighted Score of RTW OptionsScoreWeighted ScoreParameter Weightage Alternative1Alternative2Alternative2 ModifiedAlternative1Alternative2Alternative2 ModifiedTechnicalRobustness15 61 47 55 915 705 825HydraulicPerformance15 70 47 77 1,050 705 1,155Constructability 10 55 55 30 550 550 300Maintenance 10 65 45 40 650 450 400Cost 15 3 15 0 45 225 0Environment 15 59 49 45 885 735 675Social &Resettlement20 47 36 30 940 720 600Total 100 5,035 4,090 3,9556-29