Alexandra Bridge

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Alexandra Bridge, before inauguration in 1876 was named the Chenab Bridge, near Wazirabad

Alexandra/Chenab Bridge
Chenab River in vicinity of the Alexandra/Chenab Bridge, 1876

The ‘Alexandra Bridge’, constructed near the town of Wazirabad, carried the Punjab Northern State Railway(PNSR) over the River Chenab. The bridge was 9,300 feet(2830mtr) long and 100 feet (30mtr) deep. The first brick was laid on the 1 Nov 1871; and the structure was formally opened by his Royal Highness the Prince of Wales on 27 Jan 1876, and the first section, viz., from Lahore to Jhelum, 103 miles(165km), was opened for traffic [1].

The ‘Alexandra Bridge’ was designed to the metre gauge(MG) and the first train metre gauge train passed over the bridge on the 23 Dec 1875 and ran to Gujrat(Goojrat) on the new line just constructed [2]

The Punjab Northern State Railway(PNSR) , together with the associated 3 bridges, was the first attempt of railway construction under the newly formed Public Works Department - Railway Branch.
The bridges were :-

Spelling Note
Earlier town names are used in some records and shown it italics :-

Also mentioned is:-

  • River Chenab (ancient Ascesines)

Gauge Question

In January 1871 the orders of the Government of India were issued to adopt the metre or 3 feet 3⅜ inches gauge (MG) on all new railway constructions [3]. The girders for the bridges were ordered for metre-gauge weights only [4]

The background to this decision, and the later decision to revert to the 5 feet 6 inches broad gauge(BG), is fully detailed in a separate page ‘The Gauge Question’.

Preliminary Works on the PNSR

The following is from IOR/V/24/3590 "Punjab Northern State Railway - 1878-79 Administration Report on the Construction " [5]

  • 1864-69: Route proposals and surveys for the route of the Punjab Northern State Railway(PNSR) ; project approved in Oct 1869 [6]
  • 1869-70: The question of gauge was left open, and only a partial design could be made. During the six months that remained of the year, considerable progress was, however, made in the works [7]
  • 1870: the surveys and river training works of the large rivers Ravvee, Chenab and Jhelum were also well advanced[8]
  • 1871: January orders given to adopt MG and immediate effect was given to these orders[9]
  • 1871-72: The designs for the three bridges were settled . The Ravee, 33 spans of 90 feet clear giving 97½ feet between centres of piers with girders and lattice, carrying the rails above; the Jhelum, of similar design of 50 spans; the Chenab, of 64 spans of 142 feet between centres of piers, warren girders carrying the rails below. The foundations of the Chenab and Ravee were to be of three similar wells 12'6." diameter, whilst at the Jhelum the up and down stream wells were to be 10' diameter. During this year more than 100 wells were put in hand, and a quantity of materials were prepared for the bridges [10]

Construction of the Alexandra Bridge

The following is based on the “Minutes of Proceedings of Institution of Civil Engineers, 1878 - The Alexandra Bridge, Punjab Northern State Railway" by Henry Lambert and reproduced by kind permission of the Institution of Civil Engineers, London."Minutes of the Proceedings of the Institution of Civil Engineers"; Volume 54 Issue 1878. The first page of this article is available from the ICE website

Location and Practical Considerations: “The Chenab rises in the Himalayas and reaches Wuzerabad after a course of about 700 miles (1100km), its course for the greater part is through a plain, composed mainly of silt carried down from the high lands of fine sand, and the banks are mostly undefined. During the winter the river is contained in a main channel about 500 yards wide and 10 to 15 feet deep., By the middle of April, floods from the melting of the snow on the Himalayas set in, and increase in volume up to the middle of June, when the monsoon commences and lasts until the middle of September. Vast floods during this time pour down into the plains, sweeping away the river banks, destroying villages, and scouring out the shifting sand of the bed of the river to a great depth. In floods, the Chenab rises 11 feet above low-water mark, and its width at Wuzerabad is 3½ miles. The mass of the water does not flow rapidly, but the main stream, corresponding to the fluctuating deep channel, rushes through with great velocity, in a serpentine direction. This is often nearly at right angles to the general course of the river when obstacles occur. Under these circumstances the bed is driven before it, and the depth of the main current of water is more than 50 feet, moving at a rate exceeding 10 miles an hour. The ground for about half the space of miles between the banks is composed of river deposit there being a depth of 2 feet of light soil over fine sand.” [11]:-
The above is an extract from the Lambert’s Report which gives great detail about the adverse conditions requiring special civil engineering techniques.
Lambert’s Report also gives specific construction systems utilised as follows with Page No.given for details as follows

River Training Bunds: Technical details are given in Lambert’s Report pages 73-77 [12]

  • 1872-73: The river training works at the Chenab had been completed [13]

Wells and Well-sinking and Pier Construction: Technical details are given in Lambert’s Report pages 82-87[14]

  • 1872-73: Chenab, 138 out of 195 wells in the foundations of piers and abutments had been put in hand completed [15]
  • 1873-74: Chenab, 195 wells, forming 65 pier foundations, were completed, as well as the north and south abutments; and the superstructure of all but 15 piers was built. The girders were being delivered at site [16]
  • 1874-75: Chenab, the floods in the summer of 1874 caused new foundations to be sunk to three of the piers [17]
  • 1874-75: Chenab, the 15 spans remaining installed and bridge completed, the first metre gauge train passed over the bridge on the 23 Dec 1875 [18]

Later Change of Gauge

In early 1874 the Goverment called for estimates to revert to the 5 feet 6 inches broad gauge(BG). This is fully detailed in a separate page Rail gauge#Gauge Question ‘The Gauge Question’.

This decision required the engineers to re-specify the bridge structure to take the wider and heavier locomotive and train weights. Lambert’s Report pages 87-88[19] records as follows :-
“The girders had been designed to take metre gauge by Alexander Meadows Rendel, M. Inst. C.E., Consulting Engineer to the Home Government, in accordance with instructions furnished to him, and were constructed by Messrs. Westwood, Baillie, and Co. The reversal of policy finally resulted in a return to the broad gauge (BG) of 5 feet 6 inches. In order to make the bridge suitable for greater rolling loads, it was thought expedient to abolish the buckled plates and asphalt for the Trunk Road traffic, and to lay the rails only on the cross girders, together with planked footpaths for platelayers. The main girders were also set 1 foot farther apart, to admit of BG rolling stock passing freely, and the cross girders were lengthened accordingly. This made the bridge suitable for light BG engines , but whether it is to be strengthened for the ordinary engines, or whether higher strains are to be adopted to suit them, has not yet been decided.”

The modifications to the bridge structure were made and additional lines were laid to enable both MG and BG working .At the end of 1877 some alterations of the longitudinal bearers at the Alexandra Bridge were found to be necessary and were in progress [20]

The Lahore to Jhelum, 103 miles(165km) section, which included the ‘Ravi Bridge’ and the ‘Alexandra Bridge’, was converted to broad gauge and re-opened on 6 Oct 1878 [21]

Personnel

No records have been found for the PWD staff being responsible during the construction of the ‘Alexandra Bridge’

Further Information

See Punjab Northern State Railway up to 1886
and North Western Railway from 1886

References

  1. Lambert "Minutes of the Proceedings of the Institution of Civil Engineers"; Volume 54 Issue 1878, "The Alexandra Bridge, Punjab Northern State Railway" by Henry Lambert; page 71 ; Retrieved on 8 May 2018
  2. Lambert, page 91
  3. IOR/V/24/3590 ; 'Public Works Department: Railways, 1876-79' - "Punjab Northern State Railway - 1878-79 Administration Report on the Construction of the PNSR from its Commencement to the 31 March 1879" Para 7
  4. Lambert, page 78
  5. IOR/V/24/3590 ; 'Public Works Department: Railways, 1876-79' - "Punjab Northern State Railway - 1878-79 Administration Report on the Construction of the PNSR from its Commencement to the 31 March 1879" with Para. Nos. as stated from this Report
  6. IOR/V/24/3590 Paras 1-3
  7. IOR/V/24/3590 Para 4
  8. IOR/V/24/3590 Para 6
  9. IOR/V/24/3590 Para 7
  10. IOR/V/24/3590 Para 8
  11. Lambert, pages 71-72
  12. Lambert, pages 73-77
  13. IOR/V/24/3590 Para 9
  14. Lambert pages 82-88
  15. IOR/V/24/3590 Para 9
  16. IOR/V/24/3590 Para 13
  17. IOR/V/24/3590 Para 16
  18. Lambert, page 91
  19. Lambert, pages 87-88
  20. IOR/V/24/3590 Para 35
  21. IOR/V/24/3590 Para 35