Lower Pier Construction
From SkyInsight
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May 28, 2005
The lower telescope pier design consists of fifteen chimney blocks (16" W x 16" L x 8" H) stacked from the pier foundation to the bottom of the deck. The first block and four 5 foot sections of rebar were set into the concrete foundation when it was poured on May 17, 2005. The rebar was originally 10 feet long but Scott of ACI suggested cutting them in half so that it would be easier to stack the blocks. That was good because we determined the concrete blocks to be approximately 75-80 lbs apiece.
I rented an electric mixer to mix the concrete that we poured into the center and outer holes of the chimney block. Stack the blocks wasn't too bad until we added the second section of rebar. The first four rebar were in the outer holes. The next level of rebar went into the center circle. We had to make some "steps" by stacking lumber to help us reach high enough to place the blocks over the top of the rebar. Lifting and stacking the chimney blocks wasn't too bad because the three of us did it together. Lifting the 80 lb backs of concrete mix into the mixer was a real work out. I used the "5000 High Strength" concrete mix which was probably overkill but I'd rather overdo it for a more stable (i.e. vibration free) pier.
As we approached the last two blocks we realized we were going to be short of concrete so my wife made a run to Menards to get four more bags. She returned and I grabbed one bag from the pickup truck to mix right way. I sent my nephew to get the other three bags. I had made a wood form on top of the last block. My brother was concerned about the wood absorbing the moisture from the concrete and causing the edges to crumble so we placed plastic bags on the side of the word. The form was about five inches deep. We filled it with concrete and set the J-bolts in place. We only needed one-and-a-half bags so we decided to mix the rest and add it to the pier footing. We cleaned up the equipment, went to load the mixer into the truck and found that the three bags of concrete my wife bought were still there. My nephew had found three more bags in garage when we sent him for more. My wife wasn't happy about the extra unnecessary trip. I was more annoyed that I'll need to return them to the store later.
It took about four hours to build the lower pier.
