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Re: footings a beam or a slab?

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-----원본 메시지-----
보낸 사람: MRodrig273(--nospam--at) <MRodrig273(--nospam--at)>
받는 사람: seaint(--nospam--at) <seaint(--nospam--at)>
날짜: 1998년 10월 1일 목요일 오전 7:14
제목: footings a beam or a slab?

>I have a case where I have a footing that is 24 inches wide and 16 inches
>deep.  I found that the footing only requred minimum steel reinforcement.  In
>the longitudinal direction I used 3 #5 bars and in the transverse direction I
>used #4 @ 6".  I was told that my #4 bars were not needed and that I can just
>space them at 18 inches.  This was argued that the footing acts like a beam,
>which I understood, and in a beam you don't need to satisfy the 0.0018bt
>critiria.  But as I was reading the ACi.  In the flexural reinforcement
>section 10.5.4 it states that "For Structural slabs and footings of uniform
>thickness the minimum area of tensile reinforcement in the direction of the
>span shall be the same as that requred by 7.12.  Maximum spacing of this
>reinforcment shall not exceed the lesser of three times the thickness and 18".
>If my footing acts like a beam, does it span the length of the footing or does
>it only span the 24 inches in the transverse direction.
>What does everyone else use as the minimum reinforcement for the transverse
>direction for a 24 inche wide beam.
>Thanks in Advance
>Marlou B. Rodriguez, EIT
>Robert Englekirk Inc.
>Honolulu, HI

I think the footing shall be designd as a beam providing srittups and meeting beam design reqirement of ACI code.
ACI 10.5.4 can be applied to mat fdn. or similar one. Read R 10.5.4.