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| Can YOU help me across the tracks quickly? 06/07/2012 at 05:59 #33676 | |
Tallington
254 posts |
As some of you now know, the Tallington Level Crossing is to be closed at last! The present footbridge will remain for pedestrians to get to the pub, paper shop and nursery. Because of this last factor requiring pushchair access and the needs of the elderly who cannot manage the footbridge, we need to consider two DDA options - a slope or a tunnel. The slope can go in-situ but the re-opened canal tunnel would be quite a way away. What I am desperately in need of is the energy requirement for the segments of all 3 options: 1. Climbing up (and down) the 10m high footbridge. 2. Walking 100 metres on the flat. 3. Walking up and down a 100m slope of 1 in 20 (5%) All by a person of 100kg walking at 3kph. I can then use these segments to get the current and future figures to decide on the best options for Network Rail to provide and users to use. This is a practical problem that I need worked answers to ASAP please! :evil: This shouldn't take the 60 years we have waited for a bypass OR the 6 years it has taken me to get this far! It is now 7am BST on Friday 6th July - Get set - GO! :woohoo: Ken B) Log in to reply |
| Re: Can YOU help me across the tracks quickly? 06/07/2012 at 08:24 #33677 | |
Peter Bennet
5402 posts |
Is the total horizontal distance to be travelled a constant? If so then all you need the differential - which will probably be easier to work out. From memory it's height x mass x gravity. Peter I identify as half man half biscuit - crumbs! Last edited: 06/07/2012 at 08:48 by Peter Bennet Log in to reply |
| Re: Can YOU help me across the tracks quickly? 06/07/2012 at 08:52 #33678 | |
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Sacro
1171 posts |
No horizontal won't be a constant, if it was, all 3 would be 0, energy used going up would be recovered coming down (in a perfect system).
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| Re: Can YOU help me across the tracks quickly? 06/07/2012 at 08:56 #33679 | |
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Peter Bennet
5402 posts |
I'd suggest that the descent energy is negligable for your purposes, theoretically it's a negative because you are going down. Peter I identify as half man half biscuit - crumbs! Log in to reply |
| Re: Can YOU help me across the tracks quickly? 06/07/2012 at 09:00 #33680 | |
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Tallington
254 posts |
Each of the options are different distances - hence the request for figures for 100 metres so that I can do the simple arithmetic! Whilst the height is the same, I need the energy comparisons going up and down steps and slopes. Steps will be over a shorter time whilst the length of the slope will need factoring in. The weight is for a mature man or a woman with a pushchair! So many parameters to consider so I hope the answer can be determined in such a way that I can convince others! Your 'height x mass x gravity' is certainly central to the problem of the bridge and ramps, but what is the output? Watts? Calories? The word 'energy' was used as this will allow comparison with the 'on-the-flat' solution. Ken Log in to reply |
| Re: Can YOU help me across the tracks quickly? 06/07/2012 at 09:02 #33681 | |
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Peter Bennet
5402 posts |
" said:No horizontal won't be a constant, if it was, all 3 would be 0, energy used going up would be recovered coming down (in a perfect system).Yes in a perfect system = 0: but in this case the additional energy is required for the vertical vector. The horizontal (for the same distance) must be the same. If the actual path followed involves a switchback ramp then that will increase the horizontal distance. So what I think we need to know is the additioanl energy to raise the body and ignore the "gain" from the drop. Peter I identify as half man half biscuit - crumbs! Log in to reply |
| Re: Can YOU help me across the tracks quickly? 06/07/2012 at 09:07 #33682 | |
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Peter Bennet
5402 posts |
Might assist on the horizontal bit http://www.brianmac.co.uk/energyexp.htm Peter I identify as half man half biscuit - crumbs! Log in to reply |
| Re: Can YOU help me across the tracks quickly? 06/07/2012 at 09:16 #33683 | |
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Tallington
254 posts |
Thanks Peter, that is just what I need for the flat bit - now the rest! One thing I have found is that it is fairly constant that going down actually uses a third of the energy going up! There is NO gain (we don't run on wheels!) Our muscles need to resist gravity and distance is still involved (it isn't a fireman's pole!) Getting there and its only 10:15am!  Ken B) Log in to reply |
| Re: Can YOU help me across the tracks quickly? 06/07/2012 at 09:19 #33684 | |
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GoochyB
222 posts |
A 100m slope at 1 in 20 would only be a 5m vertical movement.
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| Re: Can YOU help me across the tracks quickly? 06/07/2012 at 09:27 #33685 | |
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Tallington
254 posts |
Yes exactly, so I would just double the result for 10m. The tiredness factor would even itself out on the longer distances. The explosive energy climbing 10m stairs would be greater than that. (I believe) Ken Log in to reply |
| Re: Can YOU help me across the tracks quickly? 06/07/2012 at 09:48 #33686 | |
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Tallington
254 posts |
There was a downloadable calculator spreadsheet on the link Peter suggested. I believe there are sufficient options behind the scenes in it for me to get started to determine actual values. As I live close to the crossing then I can get actual times to feed into it. Will post my results over the weekend (I'm in Uxbridge at present!) So if anyone can come up with any more suggestions in the meanwhile I am sure we can see how things work out. Many thanks. Ken Log in to reply |
| Re: Can YOU help me across the tracks quickly? 06/07/2012 at 11:01 #33687 | |
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Peter Bennet
5402 posts |
" said:Yes exactly, so I would just double the result for 10m.Don't forget that the atmosphere thins out at altitude! :whistle: Peter I identify as half man half biscuit - crumbs! Log in to reply |
| Re: Can YOU help me across the tracks quickly? 06/07/2012 at 11:09 #33688 | |
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Albert
1315 posts |
I'm having a magazine about mathematics here with the calculation of climbing and descending energy. I don't have time right now, need to work on a presentation for physics but I'll look it up soon (if I don't forget it).
AJP in games Log in to reply |
| Re: Can YOU help me across the tracks quickly? 06/07/2012 at 11:30 #33689 | |
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AndyG
1842 posts |
BD 29/04 Design Criteria for Footbridges Section 6 has some guidance notes on footbridge layouts, and the reference section may give you some further leads.
I can only help one person a day. Today's not your day. Tomorrow doesn't look too good either. Log in to reply |
| Re: Can YOU help me across the tracks quickly? 06/07/2012 at 12:55 #33690 | |
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Tallington
254 posts |
Thanks for that AndyG - the design of the bridge wasn't a criteria but the links on that page WILL help me design the road roundabouts! I spoke to the Highways Dept. earlier and he said new regs. were out since 2006! Many thanks..... Ken Log in to reply |
| Re: Can YOU help me across the tracks quickly? 06/07/2012 at 13:02 #33691 | |
bfcmik
100 posts |
Wouldn't the calculations be the same as if the horizontal was constant as you would have people going in both directions thus cancelling out the differentials?
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| Re: Can YOU help me across the tracks quickly? 06/07/2012 at 13:16 #33692 | |
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Tallington
254 posts |
The differentials are between before and after and then differentials between the 3 options! The truth is that there is going to be twice the problem not a balance! Try convincing the villagers that going to the pub and coming back the same way that they haven't spent any energy (or money)! Ken Log in to reply |
| Re: Can YOU help me across the tracks quickly? 06/07/2012 at 13:47 #33693 | |
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AndyG
1842 posts |
" said:Thanks for that AndyG - the design of the bridge wasn't a criteria but the links on that page WILL help me design the road roundabouts!TD16/07 for roundabout design criteria I can only help one person a day. Today's not your day. Tomorrow doesn't look too good either. Last edited: 06/07/2012 at 13:48 by AndyG Log in to reply |
| Re: Can YOU help me across the tracks quickly? 06/07/2012 at 13:55 #33694 | |
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Danny252
1461 posts |
It seems odd that you personally are having to do the work, rather than someone with - no offense! - experience in designing these sorts of things (NR, Highways Agency, architecture firm)? Especially as NR seems to be working out the specifics of the road bridge themselves!
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| Re: Can YOU help me across the tracks quickly? 06/07/2012 at 15:17 #33695 | |
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miker15
50 posts |
This might help: http://www.ncbi.nlm.nih.gov/pubmed/11932581 Log in to reply |
| Re: Can YOU help me across the tracks quickly? 06/07/2012 at 15:32 #33696 | |
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Tallington
254 posts |
Thanks Andy, I had just printed that section! Danny, its me that has got the knives in my back for even suggesting a bypass! Now that I have it I want more! The reopening of the Stamford Canal tunnel will be fantastic. It is the oldest proper canal in England - built 1670 - 100 years before the Industrial revolution (and the Bridgewater Canal) The roundabouts are the subject of 6 years campaigning so I want my input into their precise use.. Don't ask, don't get! (And never take NO for an answer!) Ken Log in to reply |
| Re: Can YOU help me across the tracks quickly? 06/07/2012 at 16:35 #33697 | |
GeoffM
6376 posts |
" said:All by a person of 100kg walking at 3kph.Given that average weight, I think the least efficient (most energy consuming) method ought to be deployed, for the health of the residents of Tallington! :silly: Ok, so you've picked a round number. Is the 3kph speed correct? I thought the typical level walking speed was 3mph, not kph (5kph). Climbing, okay, slower. I can't help with the maths/physics problem but have you considered the problems of a long enclosed tunnel? Lone women with pushchairs might not like that idea. A bridge might be vertically more challenging but I think most people would consider it safer. SimSig Boss Last edited: 06/07/2012 at 16:37 by GeoffM Reason: Trimmed quote Log in to reply |
| Re: Can YOU help me across the tracks quickly? 06/07/2012 at 16:51 #33698 | |
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Stephen Fulcher
2080 posts |
I would imagine that a bridge would be significantly cheaper as well.
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| Re: Can YOU help me across the tracks quickly? 06/07/2012 at 22:00 #33703 | |
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Tallington
254 posts |
Now that I am back online (and in Tallington) I can shed a little light on the tunnel! It is there - just backfilled in the late 1890's early 1900's and is supporting the 120mph trains going over it! Reopening it is far cheaper than a DDA ramped bridge and it would fit in with many of the public footpaths in the area. The 100kg was a trade off - heavy man/woman with child+pushchair. The 3kph is how we do things in the country - slowly! Many thanks for all the contributions up to now... Ken Log in to reply |
| Re: Can YOU help me across the tracks quickly? 07/07/2012 at 05:04 #33704 | |
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pilotman
189 posts |
Ken if you use consistent units (metre, kilogramme, metre/second squared) the answer will always be in joules. Maybe worth also considering the power required (joule/second or Watt) as person with pushchair might run out of steam (heh heh) and have to take a break. Ray Log in to reply |