4.1.9.5.3b Satsop River Bridge N5 (Steel Pier)

Description: Steel Pier

Pier 3- three wood pile trestle bents with stacked wood pier and steel top cap surrounded by steel retaining wall and earth.

Prototype Information

The Satsop River Bridge is a prototype scene I wished to model. A search of the internet found a couple of pictures of the trestle when it was used by the Mt. Rainier Scenic Railroad. The first photograph shows the bents were 6 pile bents, not the usual 5 pile, suggesting that the Milwaukee Road considered this a heavy traffic main line. Both pictures show a 5 pile bent made of steel with a concrete cap at the point where the timber trestle meets the plate girder bridge. You can just barely see that there is a wood frame bent resting on the concrete cap holding the wood stringer.

North Bank 1

North Bank 2

Another interesting point is that the steel bent pier had a steel breakwater protecting the bent and there was a sizable rock rip rap along the base to protect the bent from erosion.

Modeling Information

The WWSL 

Engineering

Selective compression of the pile trestle  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.

 

 

Project Process

Tool List

Materials Top cap Horizontal Brace Diagonal Brace Pile Legs Stringers Girts Outside diagonal braces Nut Bolt Washers

 

 

Process Steps

Preliminary Preparation

1. Cut the H girder and C girder for the pile
2. Distress the steel pile as necessary. 
3. Paint the wood.
4. Nut Bolt Washer  NBW) parts will be painted prior to installation

Construction

BUILDING THE BRIDGE JIGS

There will be two jigs necessary. Jig 1 is for building the pier. Jig 2 is is actually a mold for constructing the cement top cap. See Jig Construction for further information

 

1. 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.  
2. Cut the side bracing on the legs while the wood is still in the jig.  Remove the bent from the jig and 

BUILDING THE STEEL BENT CONCRETE CAP

1. Construct the concrete top cap jig. 
2. Place the concrete top cap jig on a horizontal surface. Pour plaster into the cavity.
3. Attach the steel bent to a machinist square with small rubber bands. 
4.  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.