6 BRIDGES TRACK STRUCTURE ON BRIDGES 6 5

6 BRIDGES & TRACK STRUCTURE ON BRIDGES 6. 5 Attention to approach track & strengthening, Cleaning of waterway, Checking guardrails, Painting of HFL, DL & flood gauge, bridge name board. Periods 4

GENERAL : Once a year during the prescribed months prior to monsoon, the Permanent Way Inspector shall inspect the following : i) the track and approaches of all the bridges, ii) Condition of guard rails and foot path on bridges.

INSPECTION & MAINTENANCE OF BRIDGE APPROACH: Track on the bridge approaches : i. Rail bearers and the main girders are in good line and level, ii. Incorrect seating of girders, shifting of girders laterally or longitudinally, incorrect seating of sleepers on girders and rails on sleepers, varying gauge or creep.

INSPECTION & MAINTENANCE OF BRIDGE APPROACH: contd… iii. The condition of sleepers and fastenings. iv. Hook bolts & Creep and joint gaps. & Guard rails.

INSPECTION & MAINTENANCE OF BRIDGE APPROACH: (contd. . ) v. The gauge and level of track. vi. Track on approaches & Rail joints. vii. Trolley and safety refuges & Foot paths.

Attention to track on Bridge approaches; provisions in IRPWM • Para 630 -Inspection and maintenance of Track on Approaches of Bridges: • (1) For all Bridges– (a) On the bridge approaches, sleepers with arrangement for fixing guard rails should be provided for provision of guard rails as per Para 228 of IRPWM. • (b) Full complement of track fittings at bridge approaches up to 100 metres should be provided to maintain required track geometry and effort should be made to immediately recoup deficiency noticed, if any.

Contd. . • (c) Rail level of track at approaches of bridges should be maintained as per designed L-section and dips in rail level immediately after the abutments should be avoided. The alignment and super elevation in case of curved track should also be maintained as per provisions of Chapter 4 of IRPWM • (d) Rail joints should be avoided within three metres of a bridge abutment. • (e) In case of LWR/CWR track, full ballast section as specified should be provided up to 100 metres from the abutment.

Contd. . • (f) Switch expansion joints should be provided at the bridge approaches in LWR/CWR track as per provisions. • (g) Joggled fish plate with clamps or two far end bolts on good AT welds shall be provided on bridges having length of water way as 100 m or more and on approaches upto 100 m length. • (2) In addition, for important and major bridge approaches, for a length of about 100 metres, width of cess should be 90 cm clear of full ballast section to maintain ballast profile. • (3) For maintaining ballast section, suitable ballast retaining arrangement should also be provided.

Para 431 -Inspection and Maintenance of Track on Bridge proper: • (1) Condition of track– • It should be ascertained whether track is central on the rail bearers and main girders and in good line and level. Departure from good alignment is caused by incorrect seating of girders, shifting of girders laterally or lengthwise, incorrect seating of sleepers on girders or rails on sleepers, varying gauge or creep. • Departure from level is caused by errors in level of bed blocks or careless sleepering. The adequacy of clearances of running rails over ballast walls or ballasted girders at the abutments and condition of sleepers and fastening on the run off and skew spans should be inspected.

Contd. . • 2. Sleepers– The condition of sleepers and fastenings should be checked. The spacing of sleepers should not exceed the limits laid down in Para 227 (2) of IRPWM. Squareness of sleepers shall be ensured. Sleepers requiring renewals should be marked with paint, and renewals carried out. • (3) Hook Bolts– Hook bolts shall, preferably be galvanised. These should be checked for their firm grip. Position of arrows on top of the bolts should be at right angles to the rails pointing towards the rail. Hook bolts, if not galvanised, should be oiled periodically to prevent rusting.

Contd. . • (4) Creep and joint gaps should be checked and rails pulled back wherever necessary. Rail fastenings should be tight. Defective rails should be replaced. Where switch expansion joints are provided on the girder bridge, it should be ensured that free movement of the switch is not hindered. • (5) Guard rails– Adequacy of guardrail arrangements should be checked. Correct distance between the running rail and guardrail should be maintained as per the prescribed dimensions. • (6) On girder bridges adequacy of pathways for inspection should be checked.

228 - Provision of Guard Rails on Bridges– • (1) Location– Guard rail should be provided on all girder bridges (including pre-stressed Concrete girder bridges without deck slab) whether major or minor. • Guardrails should also be provided on all major and important ballasted bridges and also on such other minor bridges where derailment may cause serious damages. • On all flat top, arch and pre-stressed concrete girder bridges with deck slab, where guardrails are not provided the whole width of the bridge between the Parapet walls shall be filled with ballast up to the top of sleeper level.

Contd. . • The provision of guardrails along the inner rail can be dispensed with, in case of ballasted deck bridges located on sharp curves where the maximum permitted speed is not more than 30 Kmph and track is laid with PSC sleepers having arrangement for provision of checkrail due to which guardrail cannot be provided. • In case of ROB/FOBs, the guard rail shall be provided on the track adjacent to a column/pier/abutment which is located within a distance of 8 m from centre of track.

Contd. . • (2) Design of Guard rails– The typical arrangement of a guard rail, with the important dimensions are shown in the sketch and table as shown in para 228(2) of IRPWM. • The top table of the guardrail should not be lower than that of the running rail, by more than 25 mm. In the case of bridges on curves with canted track, the difference should be measured with reference to a straight line connecting the running tables of inner and outer rails.

Contd. . • (3) Fixing of Guard rails– • (a) Splaying of Guard rails– In the case of through girder bridges on double lines, the guardrails should be splayed on both ends on both lines. • In the case of bridges other than through bridges on double lines, the splaying need be done only on the facing direction of the particular line. • The ends of guardrails should be bent vertically and buried and a block of timber fixed at the end to prevent entanglement of hanging loose couplings

Contd. . • However, the non-splayed end should be bent downwards after it is stopped at the end of the abutment or a wooden block provided. • (b) The fixing of guardrail on concrete sleepers on ballasted deck bridges and approaches shall be done as per approved RDSO drawings by proper tightening of rail screws

CLEANING OF WATER WAY:

CLEANING OF WATER WAY: All bridges must be inspected before monsoon and all waterway to be cleared well before of on set of monsson. During monsoon patrolman must be vigilent and when ever any obstruction to water way is seen to be cleared.

PAINTING OF HFL/DL ON BRIDGE: Para 703. (fixed by divisional engineer)

PAINTING OF HFL/DL ON BRIDGE: Para 703(4)

PAINTING OF HFL/DL ON BRIDGE: Para 703(10)

Guideline for fixing DL: Para 703(5) Girder and slab bridges

Guideline for fixing DL: Para 703(5) Arch bridges

Guideline for fixing DL: Para 703(5) Box culverts

CHECK LIST FOR PAINTING ON BRIDGES: Painting – i. Marking HFL and Danger level, providing foundation particulars and bridge name boards. ii. The date of last painting iii. The Highest Flood Level and the year. iv. The danger level has been fixed and marked on the pier / abutment. v. The direction of the flow has been distinctly marked on the abutment or pier. vi. The Full Supply Level (FSL) has been marked distinctly at all canal crossings. vii. The flood gauges have been provided at important bridges for recording flood levels and afflux.