CHAPTER 5 CIVIL ENGINEERING 5.1 GEOMETRIC DESIGN NORMS 5.1.1 General The design parameters related to the Metro system described herewith have been worked out based on a detailed evaluation, experience and internationally accepted practices. Various alternatives were considered for most of these parameters but the best-suited ones have been adopted for the system as a whole. 5.1.2 Horizontal Alignment As far as possible, the alignment follows the existing roads. This leads to introduction of many horizontal curves. On consideration of maximum allowable cant of 120 mm and cant deficiency of 85 mm on Metro tracks, the safe speed on curves of radii of 400 m or more is 80 km/h. On elevated section use of curves with minimum radius of 200 m, having speed of 55 km/h shall be adopted. There are, however, exceptional situations where due to site constraints; use of sharper curves is unavoidable. Under such situations on this project, curves of 160 m radius (safe speed of 40 km/h) have been adopted. However in underground section desirable minimum radius of curve shall be 250m for ease of working of Tunnel Boring Machine. For maximum permissible speed on curve with various radii, Table 5.1 may be referred. DETAILED PROJECT REPORT FOR PUNE METRO February 2009 1/69 CHAPTER 5 - CIVIL ENGINEERING 5.1.3 Horizontal Curves Description Underground Section El evated Section Desirable Minimum radius 300 m 200 m Absolute minimum radius 200 m 120 m Minimum curve radius at stations 1000 m 1000 m Maximum permissible cant (Ca) 120 mm 120 mm Maximum cant deficiency (Cd) 85 mm 85 mm 5.1.4 Transition Curves The existing roads along which the metro is proposed have frequent curves. However, it is necessary to provide transition curves at both ends of the circular curves. Due to change in gradients at various locations in the corridor, it is necessary to provide frequent vertical curves along the alignment. In case of ballast less track, it is desirable that the vertical curves and transition curves of horizontal curves do not overlap. These constraints may lead to reduced lengths of transition curves. The transition curves have certain minimum parameters: - Length of Transitions of Horizontal curves (m) Minimum : 0.44 times actual cant or cant deficiency (in mm), which ever is higher. Desirable : 0.72 times actual cant or cant deficiency, (in mm), which ever is higher. - Overlap between transition curves and vertical curves not allowed. - Minimum straight between two Transition curves: either 25 m or Nil. - Minimum curve length between two transition curves: 25 m DETAILED PROJECT REPORT FOR PUNE METRO February 2009 2/69 CHAPTER 5 - CIVIL ENGINEERING 5.1.5 Vertical Alignment and Track Centre (a) Elevated Sections The viaducts carrying the tracks will have a vertical clearance of minimum 5.5 m above road level. For meeting this requirement with the ‘Box ’ shaped pre-stressed concrete girders, the rail level will be about 9.8 m above the road level. However, at stations which are located above central median, the rail level will be 12.5 m above the road level with concourse at mezzanine. These levels will, however, vary marginally depending upon where the stations are located. The track center on the elevated section is kept as 4.1 m uniform through out the corridor to standardize the superstructure, except at few locations; wherever scissors crossovers are planned; it is kept 4.5m. (b) Underground sections Rail level at midsection in tunneling portion shall be kept at least 12.0 m below the ground level. At stations, the desirable depth of rail below ground level is 12.5 m, so that station concourse can be located above the platforms. Track centre in underground sections are follows. Sections where stations are to be constructed by Cut & cover and running section by TBM to accommodate 12m wide plat PF : 15.05m Sections where stations are to be constructed By NATM and running section by TBM to Facilitate construction of Stations : 22.00m Sections where stations as well as running Section as well as stations both are to be constructed cut & cover : 4.5.00m are to be constructed DETAILED PROJECT REPORT FOR PUNE METRO February 2009 3/69 CHAPTER 5 - CIVIL ENGINEERING (c) Gradients Normally the stations shall be on level stretch. In limited cases, station may be on a grade of 0.1 %. Between stations, generally the grades may not be steeper than 3.0 %. However, where existing road gradients are steeper than 2 %, gradients or for Switch-over Ramps upto 4% (compensated) can be provided in short stretches on the main line. (d) Vertical Curves Vertical curves are to be provided when change in gradient exceeds 0.4%. However, it is recommended to provide vertical curves at every change of gradient. Radius of vertical curves: • On main line (desirable) : 2500 m (Absolute minimum) : 1500 m • Other Locations : 1500 m • Minimum length of vertical curve : 20 m 5.1.6 Design Speed The maximum sectional speed will be 80 km/h. However, the applied cant, and length of transition will be decided in relation to normal speeds at various locations, as determined by simulation studies of alignment, vertical profile and station locations. Computerized train simulation studies need to be conducted with proposed gradients at the time of detailed design stage. This is with the objective of keeping down the wear on rails on curves to the minimum. DETAILED PROJECT REPORT FOR PUNE METRO February 2009 4/69 CHAPTER 5 - CIVIL ENGINEERING Table 5.1 Cant, Permitted Speed & Minimum Transition Length for Curves MAX IMUM PERMISSIBLE MINIMUM DISTANCE BETWEEN RADIUS CANT SPEED ADJACENT TRACKS ELEVATED AND AT - UNDER GROUND GRADE metres mm kmph mm mm 3000 15 80 3500 3650 2800 15 80 3500 3650 2400 20 80 3500 3650 2000 20 80 3500 3650 1600 25 80 3500 3650 1500 30 80 3500 3650 1200 35 80 3500 3650 1000 45 80 3500 3700 800 55 80 3550 3700 600 70 80 3550 3750 500 85 80 3600 3750 450 95 80 3600 3800 400 105 80 3650 3800 350 110 75 3650 3800 300 110 70 3700 3850 200 110 55 3800 3950 150* 110 50 4000 4050 150* 0 30 4000 4050 120* 110 45 4000 4150 120* 0 30 4000 4150 Notes: (a) The track spacing is without any column/structure between two tracks and is with equal cant for both outer and inner tracks. (b) Track spacing shown is not applicable to stations which should be calculated depending on specific requirement. (c) Figures for any intermediate radius of curvature may be obtained by interpolating between two adjacent radii. For higher radii, values may be extrapolated. 5.1.8 Station Locations Stations have been located so as to serve major passenger destinations and to enable convenient integration with other modes of transport. However effort has DETAILED PROJECT REPORT FOR PUNE METRO February 2009 5/69 CHAPTER 5 - CIVIL ENGINEERING also been made to propose station locations, such that inter station distances are as uniform as possible. The average spacing of stations is kept close to 1.0km. 5.2 DESCRIPTION OF CORRIDORS Two corridors have been recommended for Pune Metro Rail Project which are as under: 5.2.1 Corridor-1: Pimpri Chinchwad (PCMC) to Swargate. From dead end (Ch. – 450 m) of PCMC station to dead end of Swargate station (Ch. 16139m), the length of corridor 1 is 16.589 km, out of which 4.661 km is underground and remaining 11.570 km is elevated Including length of Switch Over Ramp(SWR). Total 15 numbers of stations have been planned along this corridor out of which 9 are elevated and 6 are underground stations. 5.2.3 Corridor-2: Vanaz (Kothrud Depot) to Ramvadi. From dead end (Ch – 684.8 m) of Vanaz station to dead end of Ramvadi station (Ch. 13790m), the length of corridor 2 is 14.925km. Total 16 number of elevated stations have been planned along this corridor. 5.3 DESCRIPTION OF ALIGNMENT 5.3.1 CORRIDOR – 1 Introduction Corridor 1 of Pune metro rail project passes across the middle of Pune city and runs in North – South direction. It originate from Pimpri Chinchwad(PCMC) in North and terminates at Swargate in South. It further can be extended southward beyond Swargate. It starts from PCMC and runs on the Eastern side footpath of NH-4 for a initial length of 6.8km between km (-) 0.450 & km 6.37. Here it further turns Eastward and crosses Mula river between km 6.630 and km 6.78; it futher moves forward and after having a right having a right turn it aligns along the median of NH-4 and runs along it upto km 8.530. It leaves NH – 4 at km 8.580; turns align along the centre of a road leading towards Agriculture University. It enters in the premises of Agriculture University at km 10.365 and runs in DETAILED PROJECT REPORT FOR PUNE METRO February 2009 6/69 CHAPTER 5 - CIVIL ENGINEERING university area for a length of 959m. It exits university premise at km 11.324. Switch Over Ramp has been planned in university area between km 10.760 and km 11.120. Alignment attains underground in university area and after exiting from it; it runs almost under Shivaji Road prior to PMC office. In PMC office area; alignment is in the East of the Shivaji road; where PMC station has been planned. It crosses Mutha River in underground position at km 13.040. Henceforth alignment runs under the heavily habitated area of Budhwarpeth & Mandai and reaches Swargate.