I am designing a hanger rod system for a running track suspended from the roof, and have included turnbuckles in the assembly for vertical adjustment. Is there any limitation in the amount of load that can be on a hanger rod when you adjust the turnbuckle? For example after the mezzanine...
If you have a pile cap with mainly vertical loads,no fixity requirements, and no embedment required such as for steel H-piles why is it still routine to embed the piles 4"-6" or so into the cap? (Say for example an intrusion mortar pile).
I need to detail connection of PT flat plate, 8" thick, to core wall which is constructed in advance of the surrounding slab. When using dowel bar substitutes for such a connection, do you use one line of dowels at slab mid-depth, a line of dowels in top and bottom of slab, or what?
I am working on a project where concrete walls will span between drilled piers. Will not have grade beams, maybe just a mud slab to set wall forms on. There are fairly heavily loaded pilasters at the piers, supporting concrete columns above. Contractor says for this condition they like to...
This is a survey. Do you normally provide a foundation wall at overhead doors, or maybe just thickened slab? This is for a 24' wide door into garage of multi-story condo. Exterior pavement has steep slope down into garage, and will likely have trench drain there. Building is supported on...
This is a survey: What is your practice in establishing amount (if any) of longitudinal reinforcing in drilled piers that do do not have any moment other than that due to piers placed off-center?
For starters:
1) ACI would let you use plain concrete if that works.
2) The FHWA publication...
For a 5' diameter straight shaft drilled pier, combination friction and end bearing, lengths 70-90', would you consider dropping off the vertical reinforcing at some point? Surrounding soils are capable of providing lateral support for the entire length of the pier.
I am designing a structural promenade slab that spans about 20' between c.i.p. walls. Walls are about 20' high, and no need to put backfill in the dead space between the walls. No need for doors or openings into the dead space. Do you normally see formwork for this application abandoned in place?
I am involved in a project where the design team is considering using carbon fiber reinforced precast panels. (One such product is "Carboncast". Just wondering if anyone has had any experience with this type of panel, good bad or indifferent. One thing we are pondering is whether cracking is...
I am looking at fire resistance requirements for pan joist floor, using IBC 2000, Type 1A construction. Per Table 601, for Type 1A, structural frame (columns and beams/girders framing into the columns) requires 3 hour, floor construction requires 2 hour. I am assuming that pan joist top slab...
This is a survey - Do you normally cut a percentage of the horizontal bars at vertical construction joints in c.i.p. walls, when the walls span between deep foundations? (Situation I am looking at has long exposed walls in underground parking area).
IBC 2003 Table 1607.1, item 33, "Sidewalks, vehicular driveways and yards, subject to trucking" specifies 8000 pound concentrated load. AASHTO HS20 loading is 32 kip axle load (16 kips at each of 2 tandem wheel locations). Seems like IBC is a little deficient in their requirements?
This is a survey. For steel stairs surrounded by metal stud construction (in other words there is no masonry wall to support the header channels), at the intermediate landing between floors, do you support the header channel by posting down to the floor below or by hanging from the beam above?
Wondering if anyone has used RAM Concept for design of parking structures, and what if any pitfalls were encountered. We purchased Concept for design of PT flat plate structure, but may be doing multi-story c.i.p. garage with one-way beam/slab system. Will have common situation where there is...
When you have a construction joint in the topping over double tees (parallel to length of tees), what is the best location for the joint? (Center of tee, over tee stem, or at joint between tees?)
I am dealing with a PT flat plate, 28' wide bay, 3' wide pour strip at quarter point of bay. Banded tendons run perpendicular to the pour strip and will terminate on each side of pour strip, anchored at center of slab. Will specify that longer slab be shored at pour strip.
1) Are there any...
This is a survey: How are you calculating long-term deflections for post-tensioned flat plate floors? Use uncracked properties? Assume a portion or assume all of the live load is permanent? Have you had any problems with deflections of this type of construction?
(I am currently doing...
For a post-tensioned flat plate condo, I am coming up with a list of allowances that will include allowance for epoxy injection of cracks. PTI has a publication "Restraint Cracks and their Mitigation in Unbonded Post-Tensioned Building Structures", that estimates the length of cracks requiring...
