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Yeah i would recommend it too to provide at least the minimum reinforcement ignoring clause 10.5.1. This is because:- Usually for usual sizes of beams and other members, minimum reinforcement is very less. If you are designing a huge member for example a beam 2m deep or a footing 1m in thickness then you dont need to (ofcouse) to satisfy the minimum reinforcement requirement because the concept will be changed and it will come in the category of deep beams or mass concrete. Anyway provide always minimum reinforcement in usual design routine ignoring ACI 10.5.1 but smartly. By this i mean, if the min reinforcement is very less then no issue, provide it. If suppose the reinforcement is much and you want to reduce it by ACI 10.5.1 then dont reduce reinforcement too much. Keep it near the minimum reinforcement calculated in usual manner. I mean lets say your minimum reinforcement is: 10 bars You want to reduce by ACI 10.5.1 and it comse to be : 6 bars then provide at least 8 bars..

Thanx Rana sir but some engineers say that even if the reinf is less by analysis one should provide at least the reinf of 10.5.1 they say it is to be better to conservative

yeah you can...design any beam in ETABS and see why some times its giving reinforcement less than minimum by code...check your self

Thank you Mr.Baz , sir if all other factors of failure are controlled then splitting can be controlled by providing sufficient concrete around the long. rebar so that the tensile stress in long. rebars is sufficiently distributed in the adjacent concrete when rebars are too close mean there spacing is less stress in two adjacent rebars will overlap in the surrounding concrete and this will lead to the splitting of concrete in the plane of rebars mean horizontal plane also this type of splitting occurs when side cover is not sufficient,2ndly if the outer cover is not sufficient splitting will be in vertical plane. sir during construction the cares you have mentioned can be assured but if the factors above i mentioned are not checked b4 preparing drawings that wud have nothing to do with the efficiency of the construction.

who told you that concrete in beams has one mode of failure (you must have heard terms like crushing , compression, tension, shear, torsion and splitting of bond between concrete and rebar) and what rebars are you referring to. please explain. Your question is all over.

yeah you are right...if it is simply supported then theoretically! no moment at top and no required reinforcement at top! but in reality we have some ethics for structures...and the CODE defines these ethics....so in reality we require bottom bars to be extended into supports....where practically there is no moment...(positve) similarly the top bars are extended upto a length equal to developement length plus d after the inflection point these minimum precautions are required to avoid failure in case of moment reversal and to provide structural integrity... generally at the discontinous ends you need one third of positive reinforcement in case of simply supported slabs but due to curling of slab edges, torsion, and temperature shirnkage and due to relative stiffness of of the beams or supports there is a need to provide top reinforcement at discontinous ends... thats y may be you have seen at some places that every other bar is bent up to give negative reinforcement area over masonry walls supports in our typical house construction in pakistan. means half of the positive moment reinforcement area is provided on discontinous egdes.. This is just a simply supported case of slabs resting on masonry walls... In case of continous slabs resting on concrete beams the negative moment is some times more than positive...

http://www.snotr.com/video/7331/The_Living_Bridge

SMRF has all its provisions listed in ACI chapter 21...this is very important to read all those provisions and its serious to deal with earthquake forces....you cannot ignore a factor as with other design procedures..You have to take the appropriate values from the code. You cannot use R factor of Ordinary or intermediate frame for special frame !