Description: Three 7- pile timber bents Piers
Prototype Information
Usually Plate Girder Bridges have steel bents or masonary/concrete piers. In this particular case, this plate girder bridge is a replacement for a Howe timber truss bridge. The Milwaukee Road MOW bridge crew repurposed the original wood bents for the plate girder bridge piers.
There are 4 interesting piers to be constructed. They will have to be kitbatched.
- Pier 1 is a x bent 7 timber pile pier surrounded by a wood breakwater with a cap composed of wood bridge ties and steel i beams
- Pier 2 is a three bent 7 timber pile pier surrounded by a wood breakwater with a cap composed of wood bridge ties and steel i beams
- Pier 3is a three bent 7 timber pile pier surrounded by a wood breakwater with a cap composed of wood bridge ties and steel i beams
- Pier 4 is a two bent 6 steel pile pier with a concrete cap.
- Each pier will be glued to a wood block base. which will then be screwed from below to the module base.
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The WWSL
Engineering
Finding a Common Standard for timber bents with wood breakwaters was a two step process. First I had to find a Common Standard double track timber trestle and the Union Pacific came through for me here. Then I had to find a Common Standard for breakwaters. I never found one, however I did find a picture of a timber bridge with a timber pier and breakwater that was just what I needed to fill in the blanks.
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Scratchbuilding
Project Process
Tool List
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Materials
Process Steps
Preliminary Preparation
- Wood parts will be cut, distressed and stained prior to assembly.
- Nut Bolt Washer parts will be painted prior to installation
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Designing the pier bents
Selective compression of the pile trestle to a wood bulkhead, 5 pole bents and 2 steel bents. The maximum height of the pile bents will be distance from the top of the section subroadbed to the bottom of the mainline ties. That distance has been measured as xxxx inches.
The concrete cap of the steel piles will be x long x wide and x high. the maximum height of the steel pile bent will be the distance from the top of the section subroadbed to the bottom of the mainline ties minus the height of the plate girder bridge. That distance has been measures as xxx inches.
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Building the bulkhead
- Construct the Bulkhead jig.
- Cut the top cap to length and place in the jig.
- Cut the legs to length.
- Glue the legs to the top cap
- Cut the horizontal and diagonals to length and place in the jig.
- Drill the NBW locations and glue and insert NWBs.
- Remove the bulkhead bent from the jig.
- Cut the bulkhead planks to length and place in the jig.
- Apply a light amount of glue to one side of the legs and replace the bulkhead bent in the jig.
- Apply weight to the assembly and allow to dry.
Building the bent piers
- Construct the pile bent jig.
- Cut the legs and top cap to length and placed in the jig. Use the jig as a guide to cut the angles on the tops of the legs.
- Cut the side bracing on the legs and secure with glue. while the wood is still in the jig. Remove the bent from the jig and flip over and
- Remove the pile bent.
- Repeat sequence as necessary.
Building the stacked wood Cap
Build the concrete top cap
- Construct the concrete top cap jig.
- Place the concrete top cap jig on a horizontal surface. Pour plaster into the cavity.
- Attach the steel bent to a machinist square with small rubber bands.
- When the plaster reaches a soft but not solid state, insert the steel bent assembly into the wet plaster. Adjust the bent for perpendicular and allow the plaster to harden.
Assemble the stringers
Paint the Bridge ties
Install the timber bents
WEATHERING THE pier
Just when I thought I had it all figured out and was ready to build the jigs I remembered that this was the WWSL and the 1st (Northern) Division was electrified and I needed a catenary pole on timber trestle configuration. I found one (but dont ask me where ... I dont remember!) 
Turn the trestle around and glue the outside girts on the other side. Let the glue set for a while before proceeding to install the inside girts and the diagonal side bracing. See Figure 17.
Install the trestle assembly in the layout by cutting the legs off to the desired length and anchoring them in scenery plaster.
Pier 4 - TBD
7.
see union pacific common standards cs34 - light traffic lines - https://donstrack.smugmug.com/UtahRails/Union-Pacific/CS-Book/i-Z8S2F3j/A
INSTALLING THE TRESTLE ONTO THE LAYOUT
cut the styrofoam it approximate shape
vertical cuts measure and recut between piles
use clay to go around piles
styro at bulkhead,
then clay to fill in between piles
then styro again to next pile
then clay again
repeat
use artist spatula to shape clay around piles and level off withstyrofoam
then dirt etc for scenery
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