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Juli, For steel, I do the software analysis and member sizing of the members using SAP2000 or RISA3D. For baseplate design, I either do manual calculations or use an in-house software. For connection design, I show the connection loads on the design drawings and provide them to a fabricator. The fabricator's engineer designs the connections, stamps his drawings and submits the shop drawings to me for review before they are issued for construction. This is the standard practice in North America. Thanks.

I do them manually. I take the reactions from SAP2000 or RISA 3D and rest all is manual. There are a number of 3rd party base plate design softwares available that you can also use. Thanks.

1. In the following explanation, I am referring to ETABS version 9.7.4, with active units of 'kip-in' for all quantities. You are probably using ETABS 13 or later version. In these later ETABS versions, systems of adoptable units have been improved, and new options of units have also been implemented. However, in order to understand the explanation given in the following, you will need to change active system of units your model to 'kip-in' for all quantities. Otherwise you might miss some important point. 2. In case of beams supported at both ends, shear force (& accordingly, shear reinforcement) is more near the beam ends, as compared to middle portion of the beam. For these beams, ETABS indicates shear reinforcement at 3 points along the beam _ at the start, at the middle and at the other end of beam span. If the beam is not subdivided into smaller parts, shear reinforcement value would generally be larger at both ends, as compared to that for the middle portion of the beam.(Beam in your attached image is indicating the similar results.) 3. Calculation of required stirrup spacing is similar, to that described for the ties in case of columns in my earlier post. 4. Upto which distance, what stirrup spacing is to be provided depends upon the shear force distribution along the beam, as will be clear from shear force diagram for the controlling load combination. This spacing will however subject to relevant provisions of ACI 318-08 Chapter 21, depending upon the earthquake zone or design category of the area in which your structure is located. 5. Now referring to the beam shown in your attached image, the value shown in the middle (0.1000), indicates maximum required shear reinforcement applicable to middle portion of the beam, whereas the other two values (0.1521 & 0.1351) are the maximum required shear reinforcement, to be placed at the relevant beam portions adjacent to supports (columns) on the relevant ends. In case your lengths in 'inches', and shear reinforcement in in 'sq.in/in.' units, you may calculate required stirrup spacing, similar to column tie spacing discussed earlier, keeping in view relevant ACI requirements. 6. For exact detailing of the 18 ft span referred beam, following further information is required: a. Overall Beam size (width & height) b. Image showing required shear reinforcement values, after changing the active units to 'kip-in' for all the structural parameters, similar to ETABS 9. It would be better & simplify the detailing a lot, if the beam is subdivided into 4-equal parts, before analysis. c. Earthquake zone or seismic design category of the area in which the structure is located. c. Structural frame system used (OMRF, IMRF, SMRF, etc.) d. Minimum reinforcing bar size used for flexural reinforcement of this beam e. Preferable bar size for stirrups (Normally #3, or #4 bars are used). Regards.

Agreed With Engr Uzair. Strap beam width is generally larger than to column dimension just to avoid massive congestion. Otherwise it has nothing to do with design.

Yes, your friend is right. It is preferable to use a beam width, about 6 inch larger than the column. It permits easy placement of column and strap beam bars at the junction of the two structural members, without interference. This extra width of strap beam also serves as a support for the column form work later on. Strap beam is also designed like other beams. For proper transfer of loads, its width however should not be less than the width of columns to which it is connected.

first point: Both methods addresses same behaviour. Moment magnification is a term used when we are taking second order effects due sway of structural system while elastic second order method(Euler) addresses slenderness of individual members. ACI code directs us to reduce stiffness of members when computing forces due to second order effects so ETABS requires us to specify stiffness modifiers and then it can calculates theses effects . Second point: Code uses Stability Index or Pu/Pc as tool to estimate magnified moments and second order effects can still be there in braced frame as there might be some slender member (Euler's equation is used in that case). Third point: Yeah one must check for slender members. I think, limiting values for drift control are not there to control structural damage instead they are for non structural damage(citation needed): hence it does not mean that there are no second order effects. Cant comment on remaining material.