Jerry: 1) Keep it wet for at least a week the longer the better. 2) No problem in stripping the forms off after 2 weeks. The concrete will be at about 2/3 strength by then. Use this as the same time
List members: The phenomina you are witnessing is called vortex shedding or oscillation. It is a function of natural frequency of the element, in this case a cylindar with l/d >25, and the weight per
Jerry: The best way is to have your rebar supplier bend it for you. This is very common if you use a rebar supplier. If you are buying bulk at HomeDepot or others then maybe you can find a rebar hous
Ken: Your foundation with 2" cl at the top is just fine. The cage shouldn't pop out of the pour. Make sure your have at least 3" clear at the bottom and sides. You use conc. pour blocks at the bottom
Paint the rebar is a no/no unless the design has accounted for the lessened bond value of the rebar. There is no reason to paint the reinforcing. Hank Lonberg, P.E.,S.E. / KR7X Lonberg Design Group,
Jerry: Look in your yellow pages under concrete suppliers to find a source. I normally specify "Masterflow 928" by MasterBuilders or equal. Sika chemical is another manufacturer. What you want is a n
Jamie: With the T type base from US Towers, the grout seals the under side of the t sections and the portion of the anchor bolt above the concrete and the underside of the t from corrosion. It does h
Mike: Unless you live in a very corrosive enviroment, say coastal closer to the equator I would not worry to much. At least you can see the exposed bolts during scheduled maintenance times. The bolts
George: That is pretty close to how it is. For everything but columns,elevated beams, and shear walls we spec stripping is ok after 7 days, for the execptions we use 14 days. 73 Hank Lonberg, P.E.,S.
Mark: Thermoweld, Cadweld, Furseweld Exothermic weld are all vendor names used by different companies that supply the components for external fusion welding materials to industry. The products are al
Jim, Alan others $250.00 is very cheap for what you want. For all the reasons Jim itemized and many others $450.00 would have been my minimum fee estimate for the work depending on the installation a
Another idea may be to use 4130 tool steel. Find a screw and bolt manufacturer (fabricator) in the yellow pages and see if they will fab up a pin in the diameter and length you need. Just a thought.
Pete and List: LRFD is a valid steel design code in the US, "Load Resistance Factor Design", and is allowable under all the building codes. It is sometimes called strength design method as opposed to
Rick: No testimonial, but the statement that the antenna area is irrelevant and does not matter will not cut much slack with the local permiting officials, at least in my experience. This operating p
Peter: If you have a report sealed from your PE that states what you said, submit a copy to your building official. The sealed document attests to the strength and conformity of the structure with re
Mick: A possible fix depending on how you are at welding or know someone who is a certified welder is to trim the legs down to say 12" long vertically. Weld some channel legs to the stub legs say 8"
Roger etal: You are partially correct and partially incorrect. You can't eliminate basic vector statics from the argument of the usefullness of torque arms. I specifically mean the style used for 55g
Chris: Bingo and you are the winner! Regards Lonberg Design Group, Ltd. Hank Lonberg, P.E.,S.E. / KR7X President _______________________________________________ See: http://www.mscomputer.com for "Se
Tom: When I refer to a star or six point guy arrangement I mean 2 guys from each guy point on the tower. With 3 anchor points on the ground you get a 3 pointed star in plan. I am rethinking my earlie