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Mill Creek Central
Trestle - Installing Beams II The installation of the beams between the north abutment and tower number 4 are described in the Installing Beams I page. The installation of the remaining beams is described here.
The ground between towers 4& 5 is fairly flat so we were able to use the backhoe to get the beams for that span into position from the west side. We had cleaned that area the previous week to make this possible. These 22 foot long - 12 inch tall beams are the biggest on the trestle. The beam on the west side went up without a hitch. The hand winch started to malfunction when we had the east side beam about halfway up. We replaced the winch with a come-along and finally got that beam on the towers. This was the last of the I beams, the remaining beams are lighter and shorter structural tubes. That was also the last of the hand winches; all we had left was an electric wench. We spent the rest of Wednesday getting the six structural tubes drilled and wire brushed and primed. Rain was forecast so we moved them into the steaming bay. Thursday it rained again but we were able to get the black paint on the beams. Thursday night it poured again. Friday was the day to put up those last six beams. A quick look at the slippery hillside convinced us that we couldn't get the beams to the sides of the towers. We decided to install the pair between the south abutment and tower 7 first by using the electric winch to drag the beams from the south abutment to tower 7. We used the backhoe to get the first beam to the abutment. Bad ideal; it sank into the relatively new fill. After that first beam was in position we started to move the backhoe out and it started to slide off the fill. Dozer to the rescue. We used the Kubota for the rest of the beams. It is lighter, has a narrower wheel base and has 4 WD . The second beam went into place with little difficulty. We used the welder to provide ac power to the wench. We positioned the beams between tower 7 and the south abutment on their sides next to each other. We then dragged the beams for the tower 6 - tower 7 span from the south abutment over these two beams using the winch on tower 6. We were too busy to take any photos
All the beams are up. The remaining work to be done on the beams is to align them, insert shims where required, install the plates and angles that tie adjacent beams together and to tighten all the bolts. That work won't produce any interesting photos so we'll end this page here. The next major part of the project is the deck ----- look for a page on the deck in a few weeks. A bit of reflection ---- after we had the first tower up in August we put together a schedule for the remaining work on the towers. The goal was to try to get all the towers up and hopefully one or two beams up by the final meet of the year on October 20-22, 2006. The photo above was taken on October 21, 2006. We did much better than that original schedule. The project was no less difficult than originally thought and the weather was much wetter that normal. The success to this point is due to the many enthusiasts who helped. The next step is to do the deck as documented in Installing the Deck |