Removing the Top Deck and the old timbers

Now that we have the foundation upgraded - And by the way, thank goodness that I was able to upgrade the original foundation since starting over would have been an even bigger job than what was undertaken.

So, the next step is to remove the top deck from the wooden members that comprise the structural component of the bridge - The 12" x 10" x 20' timbers that the top deck is attached to.

You can see from the picture that the top deck is very weathered. The breaks on the sides are from weathering and finally rotting until they break through and the ends fall off. Not a pretty site especially if you were walking along the side. You can also see the plywood patch in the center which covers a broken deck piece that left a hole! What appears to have been happening is that the top runners that the tires drive on hold water between them and the top deck pieces.

After 25 years or so of holding water between the pieces, ants, and probably bacteria, mold etc. have taken their toll. The deck pieces rot out and the ends and center falls out. The option only to replace the top deck ignores the posibility that the structural members have also rotted and may fail due to unseen problems. One of the members had obviously been attacked by wood ants - Big black ants that burough into the wood and build nests. Not what you want in a structural member!

In order to replace the rotting deck top and for safety, the structural members need to be replaced. My brother-in-law works for a construction company that had left over steel structural members from a retaining wall. These twin "C" channel galvanized members were used to replace the wooden beams that were to be removed. The advantage of using galvanized steel is obvious that during what I expect is the rest of my lifetime, the bridge will remain viable and is not expected to rust or be attacked by ants!!

I found a place under the top deck where the wood ants had burrowed into the wood and had hollowed out a nest. This type of damage is not visible unless the top deck is removed. Once removed, it was obvous that the wooden members had to be replaced. As you can see from the picture above, moss is growing on the side of the structural wood members - A hint of what was to be found under the deck.

So, the wooden members across the river were removed and the "C" channels were loaded across the wooden beams after the top deck was removed. You can see the exposed wooden beams in the picture.

Once the top deck was removed, the beams shown below were moved one by one across the wooden beams. Unfortunately, no help moving the beams was available so I used a couple one inch by two foot pieces of pipes to roll the steel members across the wooden beams.

This technique worked incredibly well. One at a time the beams were moved across the wooden beams until two of them were across the river. Once two were on top of the wooden beams, two wooden beams were removed. So, before removing the beams, the ends need to be dug up, and a wedge needs to be placed under the end so that they can be pulled out with a chain and a Jeep Cherokee (preferably champagn color).

Take a look at the next pictures showing the removal of the old timbers.


You can see the beams on top of the two timbers and one of the timbers about to be removed. Here is a better shot of how the timbers were pulled from the foundation. Until next time; be good.

Shoring up the foundation

OK, now that we have the forms set and a start at poring cement, the main part of the cement work begins. The river was low enough that the poring of cement didn't come close to the river with the exception of the later part of the cement.

As a side note, I am a zealot and advocate of keeping our streams clear and pristine. I am probably too careful about not letting contaminants get into the stream. I believe it is our duty to keep the streams clean and pure. Between the time when I was a kid and today, it appears that we have lost at least one spices of frog in the stream shown. The Northern Leopard frog pictured. (curtsy of Greg Lasley Nature Photography) When I was a kid, we used to wade the river down to an "S" turn where the log jams from the winter run-off used to build a small pond. In the pond there were always leopard frogs. My cousin and I would catch and release these frogs. Unfortunately probably due to urban sprawl and development along the canyon, these frogs are gone. More disturbing is the fact that each year the river which is fed by streams seems to be ever lower than the previous year. Take a look at the what the frog may have looked like in 1976 along the river. Sadly, I have not seen a leopard frog like this for at least 25 years - Maybe longer.

So due to the notion that we have lost habitat and possibly a species of frog in this river, I am dutifully careful of not getting silt, sand, cement or other contaminants into the river. Therefore, the cement forms were carefully installed, and carefully filled so as not to contaminate the stream. The west side bank was completed first. Take a look at the cement that filled the forms.

Once the forms on the West side were filled, the East side was built and filled - Notice the silt protection or barrier dam to keep debris from entering the river. Also notice the beat-up bucket used to pour cement. This bucket was my friend and work partner for a very very long time. Each bucket of cement was carefully poured with this bucket about 90 bags of cement in all; a bucket at a time.

Rebuilding a bridge

Several years ago, my uncle built a bridge over a stream on property that he owned. The bridge was used for about 30 years. Originally built from rough cut timbers the bridge was succumbing to the ravages of time and showing signs of crumbling. As seen in the pictures below, the wood was rotting and the foundation was being undercut by the stream. In order for the bridge to last, it must be rebuilt to stand the test of time.

As you can see from the pictures, the top deck of the bridge has weathered badly. The deck timbers are one by six by twelve feet spanned across 20 foot by one by ten timber runners. During the inspection, one could see that the timbers were in pretty good shape. One or two of them had some weather damage and may be candidates for replacement. I wanted to ensure that if possible, during my lifetime, I wouldn't have to replace the timbers or top deck because of weathering.

The first step in the restoration was to shore up the foundation. The original foundation has held up pretty well for 30 years of spring flooding but could be built up to prevent undercutting. Prior to putting any cement down, a plan was devised so as not to harm the natural river habitat. The plan entailed a diversion dam so that no silt would get into the river.

The part of the foundation that was not in the river was the first to be repaired. First things first was to gather some rocks that could be used to strengthen and take up some of the space of the cement so I didn't have to fill such a big void with only cement.

The next thing was to create the forms out of discarded chip-board and use stakes to hold the forms. Because the cement was mixed by hand it took forever to fill the forms. As the batches were mixed and the forms filled, more forms were put up and filled. You can see in the next pictures two of the forms were filled.

With the experience that I gained by building the GPIO board, I used my experience to complete my senior projects class at the University. The Senior Projects class is a class that a potential graduate demonstrates their ability over about 2/3rds of a year.

The project that I built with the help of two individuals, was a disk drive alignment tool. Back in those days, most of the disk drives were build by Shugart or compatible companies. The heads tended to drift over time and with a special alighment disk a technician could re-position the head in the correct place over the media. A Real simple technique however; the alignment tools were very expensive. Something like the item pictured would be in the $900 to $1000 range today - Not an easy expense for a person paying for his own school!

The board was hand wired using point to point wire wrap wire. Each point was hand soldered. The system has RAM, ROM and enough IO to provide Zero track sense, track pulse for the next track, keyboard input and display output. I was able to score an accolade in the form of an outstanding accomplishments certificate.


Below is the GPIO board and how it was used in the Color Computer. The Color Computer was a fantastic platform. All graphics, memory management, and other functions were done exclusively by the 6809 processor. One unfortunate problem that the system suffered was that it needed an occasional re-boot. The system didn't have an operating system as we know them today.

Halloween Tricks

- I really didn't want to post about myself however this is about things that I have built therefore, as an introductory, I will post a little about what I have done in the past - Especially Halloween animations.
Starting sometime in 1996 or there about, I built a pop-up skeleton housed in a casket. It was pretty rudimentary, but it used a Radio Shack Color Computer as the control system. I built the "GPIO" board from scratch and did the programming in (6809) machine code - Ah those were the days ;-)

Here's a picture of the IO board - A lot of thought went into the creation of the board; it uses an 8225 GPIO chip, some support logic, transistors for output and probably the best part is the MOC3010 and Triacs used to run the 120V air solenoids.