1000 SE EVERETT MALL WAY BASE FILE 2018-01-01 MF Import

Plan Check 172� Larry Callahan Au9ust 9, 1985 Page Four e. I:eferring to the retaining wall section on Sheet S-1, Chapter 14 of the CRSI Handbook recommends placement of dia9onal bars at the back of the base of the wall stem to resist the tension crack between the ;tem and the vertical reinforcing. f. Referi•ing to Cetail 6/S-1, corrosion protection of the exposed struc- tural steei �nembers should be sper,ified. Section 2607(h). Carbon content or r;Aldable reinforcing bars should also be specified. Sec- tion 2603(f) and 26-8 UBC Standard 4. Concrete columns and footings below ductile frames: a. The 24" x 30" concrete columns, supporting the steel columns of the ductile moment frames, should be detailed as ductile columns. Section 2312(j)1.I b. Closed tie sp�cin9 for these columns, in the top and bottom 30" of the column height should not exceed 4". Section 2625(f)4.A. The cross sectional area of the ties should be computed from Equation 25-4. c. Dovrels matchin9 the vertical reinforcing o:` these columns should be specified for connection to be footings below, and should extend high enough into the columns to lap a minimum of 30 bar diameters within the middle 1/2 of the column height. Section 2625(f)3. Dowel embedment and hook dimensions in the footings should be shown to develop the bars. d. In the footin9s themselves below these columns, closed ties should be provided around the flexura', reinforcing. Section 2607(1 ) e. The anchor bolts between the ductile steel columns and supporting concrete columns are detailed on Sheet S-7. These anchor bolts are as large as 2" in diameter in some cases but are placed near the corners of the columns. The adequacy of the concrete shear cones should be justified by calculations. Section 2303(b) f. The 3/8" x 4" square plate washers on these anchor bolts have a bearin9 pressure �t the concrete-to-steel interface as high as 14 ksi. The adequacy of the stress transfer between the steel and concrete should be justified by calculations. g. The ability of the footings to transfer the frame moments to the support- ing soils, as considered in the submitted calculations, was based solely on load cnmbination equation 9-2 of Section 2609(c). However, equation 9-3, i .e. relying only on the dead load of the structure (not live loads) to resist the overturning moments, will govern the design.