let's be specific. 21.7.6.4e says "horizontal reinforcement in the wall web shall be anchored to develop fy within the cinfined core of the boundary element." the ld here should follow chapter 12 or 21.5.4?
you can find some similar clause all over chapter 21.
i have a question about lap splice under seismic load. ACI318-05 21.5.4 addresses development length of bars in tension. i think it only applys to the joint of SMF. when we calc the splices in beams, columns, foundations, we still use the equations in chapter 12. 21.7 does say the splice in wall...
ACI 10.5.4 says the slabs of uniform thickness Asmin in the direction of the span shall be the same as 7.12
say i have a 6" one way slab. according to 7.12 my minimum is 6*12*.0018=.1296in^2/ft. i need double layer bars. through calc i know #3@12 which is 0.11 in^2/ft is good enough for bending...
just printed a copy of AISC 341-10. havnt got a chance to read it yet. can anyone explain to me when we are required to use highly ductile members or moderatedly ductile members? thanks a lot.
to gumpmaster
i dont think it is going to help. when you use SDF method to design the member, the reaction of the supported member will be used as the load of the supporting member.
say you ignore the composite action of the beam and you get the reaction of 10 kips for the beam and you will...
external. of course the the overpressure is big enough for me to do a dynamic analysis. say it is 6 psi.
I did a search this morning but didnt find what i need. maybe i will do a search again.
here i have some questions about roof design for blast load.
we are going to frame the roof using steel beams and girders with steel deck and concrete topping.
the first question is about the deck. are there any type of composite deck intended for blast load?
the second is about the beam and...
according to ACI 318 chapter 21 longitudinal bars in beams of special moment frame are not allowed to be spiced within joints and 2 times of beam depth measured from the face of joints. if i am not misundstanding it the bottom bars in a continuous beam shall be spliced in the mid span of beams...
thanks taco. that is i usually do also. if the equipment need to be anchored to pad without considering friction i just think the pad to soil should not consider friction also for the same reason. just try to be consistent. anyway. it seems like nobody really think that way. thanks a lot.
ASCE says that all the components shall be bolted, welded or positively fastened to their supports without considering friction. i dont want to debate what is a nonstructural component or what is a nonbuilding structure. i believe a skid, a hvac unit or a transformer supported on a floating slab...
i do think we need to anchor the foundation as i mentioned above even for a small one or it may clide with something else which is why i post it here. code maker may need to add something for anchoring the floating slab to make the code more reasonable and less funnier at least be consistent. if...
the unit i am dealing with is very short. i mean it's almost impossible to tilt it unless soil moves vertically in 2012. without anchoring the floating slab could slide and clide with something else? i think the code should address the floating structure differently probably. an flying airplane...
thanks everyone. i guess i get some kind of answer for myself. methink the footing needs to be anchored to the soil to resist the seismic load is because the corrent code method assumes a pseudo force applied to the structure from the air. but the reality is upper structure gets seismic load is...
well the real seismic load the unit gets is from soil through the pad although code assume a fake load from the air. probably it is better not to secure the pad to the soil to get less seismic load. i dont know.
