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Level Crossing depth/width to allow for wheel flange

HauteSaoneFrance

Joined: 2-01-14

Topics: 27

Replies: 91

Posted: Mon 2nd Jan 2017, 4:01pm
Level Crossing depth/width to allow for wheel flange

I'm soon to start work on establishing level crossings with the track concreted in. How much depth should I allow for the wheel flanges and width too if I don't make the lower level right across the inside of the track as has been suggested for easy cleaning
 

Replies To This Post

Peter Beevers

Joined: 9-10-01

Topics: 3

Replies: 134

Posted: Mon 2nd Jan 2017, 4:24pm

The easiest way is to sink a channel into the concrete, with the inner face as the running rail. Use a deep channel so that stones (ballast) do not get carried into it and get stuck thus causing derailments. For instance, ex-BR point rodding (about 35x35x5), is not deep enough.
 

HauteSaoneFrance

Joined: 2-01-14

Topics: 27

Replies: 91

Posted: Mon 2nd Jan 2017, 5:00pm

Thanks Peter, I've got quite a lot of track made up from 30 X 12 flat bar welded to 25 X 5 flat bar transversely at 250 mm centers. One level crossing is almost entirely a 9 m radius amounting to a quarter of a circle with a straight section ongoing, vehicle and pedestrian crossing is required as is on another straight crossing over a 4 m wide driveway. The track for the radiused crossing is pre made in the workshop. It would be difficult to form a substantial channel section to a radius with the limited capacity power bender that's available.

Other track available is Medium steel rail from Cromar White

I did inquire about bending 125 X 65 channel to a radius for bridge building from the West midlands company ANGLE RING the service doubles the base cost of the steel only.
 

Xz

Joined: 1-01-92

Topics: 17

Replies: 244

Posted: Mon 2nd Jan 2017, 7:08pm

The best type of level crossing for our gauge has long proved to be lowering the concrete for the full width of the track. 1/2" (12mm) is plenty. Stones have nowhere to get trapped and the whole thing is easily swept when required. Any guard/check-rail will always trap the wrong sized stone. The 1/2" drop has no effect on crossing vehicles.
 

HauteSaoneFrance

Joined: 2-01-14

Topics: 27

Replies: 91

Posted: Mon 2nd Jan 2017, 7:28pm

Thanks Xz for that reply, I can see the sense in not having a narrow slot for stones etc to get trapped in, all you need is a 7/1.4 inch brush to keep it free of debris. Is there a marketing opportunity here for a brush manufacturer to supply that special width brush? Seriously a 12mm lowering of the concrete between the rails should not lead to claims from anyone as to a trip hazard which is usually considered as being in excess of 25 mm

Thanks and a happy new year to all !
 

colinedmondson

Joined: 9-08-09

Topics: 3

Replies: 82

Posted: Mon 2nd Jan 2017, 10:54pm

It is possible to use bar section for rail and check rail, and fill the gap with closed cell neoprene strip, which is used for expansion joints in buildings. Trimmed flush, it keep the concrete out and also stones and water once the concrete has set. The flanges just push it down and it pops right back up.
 

HauteSaoneFrance

Joined: 2-01-14

Topics: 27

Replies: 91

Posted: Tue 3rd Jan 2017, 12:23pm

Thanks for the replies, I'm inclined to go for the 1/2 inch lowering of the concrete for the whole width between rails. The practicality of of laying in boards to allow for this depth will preclude easy pouring of the concrete from a ready mix truck. The proposed formwork is steel plate sides with a ledge of small angle (say 25 X25 to sit the premade rail sections on i'e. the transverse flat bars to which are welded the rail itself. This will give a level right across the whole formwwork mould and the open top will give easy access for the concrete power vibrator. My scheme is to have a steel shovel made to fit exactly between rails and to effectively scoop out a 1/2 inch depth of concrete at an appropriate time after pouring, I realise the time this is carried out and the concrete slump is critical to avoid the scooped out area -re filling itself. Has anyone tried this method?
 

Xz

Joined: 1-01-92

Topics: 17

Replies: 244

Posted: Tue 3rd Jan 2017, 3:28pm

Its probably more usual to lay the concrete inbetween first. Then lay a board in the dip when set, and pour the outsides. Saves the slump problems. If you do it the other way round there is a small risk of displacing the rail. Make up a simple striker board to get your level.

Bob.
 

HauteSaoneFrance

Joined: 2-01-14

Topics: 27

Replies: 91

Posted: Tue 3rd Jan 2017, 9:24pm

I can see the logic in that Bob, if you put a board in between the rails at the outset then with a 400 mm wide form you have insufficient space for the ready mix truck chute to discharge the concrete, I did a long retaining wail last summer at 400 mm wide it was about minimum for the truck to discharge into. Nevertheless I can make up some boards to have ready to slot in between the rails on concreting day.

Thanks everyone for the advice. I will post on here with the results when it happens, right now it's a snowy scene here like a Christmas card

 

HauteSaoneFrance

Joined: 2-01-14

Topics: 27

Replies: 91

Posted: Wed 4th Jan 2017, 4:43pm

The first reply to my question suggested using channel back to back fine for straights but I have a least one crossing where it's part of a 9m radius so the channel would have to be rolled. The quote for this came out rather expensive but I may have a local source now at lower cost. What size channel should I consider if it's set into a concrete form say 400 wide X 300 deep? The smaller sizes of channe seem to be 50 X 25,
76 X 38 & 100 X 50 for roiling larger sizes mean the availability of capacity locally diminishes
 
 
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