ojuego
Civil/Environmental
- Jan 25, 2014
- 17
Hi,
I am designing a flume to carry stormwater, a cross section depiction of which is attached. We want to have an expansion joint every 20 feet to aid in removing the construction if there is ever a problem with one of the utility lines that is to be buried underneath the flume. I do not want water leaking through the expansion joints, so I want to have a waterstop in between sections. Usually in construction like this (but when it does not include the need to carry water) I include at the expansion joints some dowels to keep the alignment of the construction. The walls (and floor) of the flume are to be only 5 inches thick, and that thickness must include both the vertical and horizontal reinforcement that I am planning on having. The entire outside height of the flume, from the top of the flume walls to the bottom of the flume floor, is to be only 1 foot 1 inch (1.083 feet). So there is some uncertainty about whether or not the steel reinforcement is really even needed or not. But I am still planning on having it "just in case". Because of the thin walls of the flume, and the need for 3" clearance to each unformed surface, the location of the tensile steel can not really be on the tension side of each concrete wall (the side furthest away from the backfill to go next to the wall), but will instead be on the compression side of each wall. Partly because of that, I am planning on using fiber reinforced concrete, to give slightly added strength for the whole wall, but most importantly for the tension side of each wall (which happens to be the part next to the inside walls of the flume). The question I have is whether or not there is a way to include BOTH a waterstop AND dowels at each expansion joint. The problem is that there will be very little room between the dowels and the other reinforcing (the vertical and horizontal bars). My first tendency is to think that such little room does not really negatively impact the structure because the horizontal rebar is not really providing needed strength, but instead really only providing crack control, and because the limited length of the dowels (extending to 12" into each of the adjoining concrete sections) means that only the first vertical rebar will be encroached on by the dowel, because the vertical rebar is to be #4s spaced at 12" on center. If that is the case, then it seems that the dowels can be placed without having negative effects. What do you think? And do you have any other ideas for achieving what is sought?
Thanks!
I am designing a flume to carry stormwater, a cross section depiction of which is attached. We want to have an expansion joint every 20 feet to aid in removing the construction if there is ever a problem with one of the utility lines that is to be buried underneath the flume. I do not want water leaking through the expansion joints, so I want to have a waterstop in between sections. Usually in construction like this (but when it does not include the need to carry water) I include at the expansion joints some dowels to keep the alignment of the construction. The walls (and floor) of the flume are to be only 5 inches thick, and that thickness must include both the vertical and horizontal reinforcement that I am planning on having. The entire outside height of the flume, from the top of the flume walls to the bottom of the flume floor, is to be only 1 foot 1 inch (1.083 feet). So there is some uncertainty about whether or not the steel reinforcement is really even needed or not. But I am still planning on having it "just in case". Because of the thin walls of the flume, and the need for 3" clearance to each unformed surface, the location of the tensile steel can not really be on the tension side of each concrete wall (the side furthest away from the backfill to go next to the wall), but will instead be on the compression side of each wall. Partly because of that, I am planning on using fiber reinforced concrete, to give slightly added strength for the whole wall, but most importantly for the tension side of each wall (which happens to be the part next to the inside walls of the flume). The question I have is whether or not there is a way to include BOTH a waterstop AND dowels at each expansion joint. The problem is that there will be very little room between the dowels and the other reinforcing (the vertical and horizontal bars). My first tendency is to think that such little room does not really negatively impact the structure because the horizontal rebar is not really providing needed strength, but instead really only providing crack control, and because the limited length of the dowels (extending to 12" into each of the adjoining concrete sections) means that only the first vertical rebar will be encroached on by the dowel, because the vertical rebar is to be #4s spaced at 12" on center. If that is the case, then it seems that the dowels can be placed without having negative effects. What do you think? And do you have any other ideas for achieving what is sought?
Thanks!
