Proposal for an advanced bridge repair model
Posted: Sat 29 Mar 2008 8:43 pm
The question of bridge repair modelling has bubbled to the surface again. I want to propose a new model and let everyone vote on it. Here is the proposed model:
Bridges will have a repair time that is no longer a single period of X hours regardless of bridge type (the old model). The proposed model will take into account the following factors:
1. Bridge type (rail or road)
2. Bridge construction (wooden or metal)
3. Bridge span length (between 200 m and 5940 m)
The rationale is that rail bridges must be built to be sturdier than road bridges, while metal bridges take longer to build per metre than wooden bridges. Finally, short bridges should be faster to build than long bridges. I propose that the DCS contain a slider to set the "base repair time" for a a "standard span" of, say, 400 m on a wooden road bridge. Then for any particular destroyed bridge, the base repair time is multiplied by the following numbers to give the actual repair time:
Construction Factor: wooden = 1, metal = 1.5
Type Factor: road = 1, rail = 1.5
Span Factor: = (Bridge Span Length)/400
As an example, if the base repair time was 5 hours (a wooden road bridge of 400 m length would take 5 hours to repair), then a metal rail bridge of length 1000 m would take
5 x 1.5 x 1.5 x (1000/400) = 29 hours rounded up
while a metal road bridge of length 200 m would take
5 x 1.5 x 1 x (200/400) = 4 hours rounded up
I guess we can discuss the choice of the red numbers and whether they should be on sliders in the DCS. What do you think of the general bridge repair proposal? FYI, the following is a breakdown of bridge lengths in SEOW.
Span (m) Number of bridges in SEOW
200 903
283 1277
400 1471
560 1
566 891
600 315
800 91
843 1
849 101
1000 26
1131 20
1200 12
1400 5
1414 9
1600 1
1697 2
1800 2
1980 3
2000 1
2263 1
3111 2
3400 1
4243 1
5940 1
Any feedback?
Cheers,
4Shades
Bridges will have a repair time that is no longer a single period of X hours regardless of bridge type (the old model). The proposed model will take into account the following factors:
1. Bridge type (rail or road)
2. Bridge construction (wooden or metal)
3. Bridge span length (between 200 m and 5940 m)
The rationale is that rail bridges must be built to be sturdier than road bridges, while metal bridges take longer to build per metre than wooden bridges. Finally, short bridges should be faster to build than long bridges. I propose that the DCS contain a slider to set the "base repair time" for a a "standard span" of, say, 400 m on a wooden road bridge. Then for any particular destroyed bridge, the base repair time is multiplied by the following numbers to give the actual repair time:
Construction Factor: wooden = 1, metal = 1.5
Type Factor: road = 1, rail = 1.5
Span Factor: = (Bridge Span Length)/400
As an example, if the base repair time was 5 hours (a wooden road bridge of 400 m length would take 5 hours to repair), then a metal rail bridge of length 1000 m would take
5 x 1.5 x 1.5 x (1000/400) = 29 hours rounded up
while a metal road bridge of length 200 m would take
5 x 1.5 x 1 x (200/400) = 4 hours rounded up
I guess we can discuss the choice of the red numbers and whether they should be on sliders in the DCS. What do you think of the general bridge repair proposal? FYI, the following is a breakdown of bridge lengths in SEOW.
Span (m) Number of bridges in SEOW
200 903
283 1277
400 1471
560 1
566 891
600 315
800 91
843 1
849 101
1000 26
1131 20
1200 12
1400 5
1414 9
1600 1
1697 2
1800 2
1980 3
2000 1
2263 1
3111 2
3400 1
4243 1
5940 1
Any feedback?
Cheers,
4Shades