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Yes. How? Go through the following paragraphs. In case of ASD, service loads are used, and both dead and live loads have same load factor of 1. On the other hand, considering the the basic load combination of 1.2 D + 1.6 L, dead load (DL) has a load factor of 1.2 and live load (LL), a load factor of 1.6. Now consider two simple examples. For the first example, assume that a certain beam has to carry a DL of 30 kips, and a LL of 10 kips. For this beam, total design service load for ASD method will be DL+LL=30+10 = 40 kip. For the Strength Design, basic design load will be 1.2 DL+1.6LL = 1.2(30)+1.6(10) = 52 kips. Strength Design load in this case is (52-40)/40*100 = 30% larger than the Design Load for ASD. Now, for the second example, assume that there is another beam, similar to that in the first example, except that the DL & LL values are reverse of those in first example i.,e., now DL = 10 kips, & LL = 30 kips. Total Design Load for ASD method is now DL+LL=10+30 = 40 kip (same as in first example). However, design load for Strength design changes and it is now 1.2 (10)+1.6(30) =60 kips, which is (60-40)/40*100 = 50 % larger. Thus, it is very clear that for both the examples, Design load is the same when using ASD method, and resultantly the member size & reinforcement will also be the same. However, since Design load for Strength Design method is larger in second example (when LL is larger than DL), a comparatively larger member size or reinforcement will be required. Thus, ASD method is generally economical (as compared to Strength Design method) when the live load on a member is larger than the dead load. Regards.

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Some portion of slab is used by many engineers to take into the account the effect of line load on the slab. Many call it a beam, because the reinforcement arrangement resembles like a beam. But it cannot technically be called a beam; beam is a member that attracts force by virtue of its stiffness. Since, the thickness of so called beam is equal to that a slab, it cannot attract forces. It is a simplified way of taking into the account the effect of line load on slab; by arranging reinforcement in this way, one assumes that the effect of line load will be limited within the width of so called beam. So the width of the beam will be decided by the design moment. The beam will be only designed for the load of the supported wall, or the load of supported wall + the load transferred by the wall from upper levels. The so called beam cannot take any load from adjacent slab area, as it does not have the stiffness to attract any load. So tributary area thing is not applicable to that member. If you understand what is written above, you should conclude that there is no need to check the deflection. In many cases, this way of locally reinforcing the slab ( so called concealed beam) will not be able to support the load transferred from above levels, unless you increase the thickness of slab.