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<br />than that given by <br /> <br />200 <br /> <br />Pmin = fy (Equation 10-1, 1973 U.D.C.) <br /> <br />unle~s the a7e~ of reinfor~ement provided at every <br />sect~on, POS~t1ve or negat~ve, is at least one-third <br />greater than that required by analysis. In T-beams <br />and joists where the stern is in tension, the ratio <br />p shall be computed for this purpose using the width <br />of the stern. <br /> <br />In structural slabs of uniform thickness the minimum <br />amount of reinforcement in the direction'of the Span <br />shall not be 17ss than that required for shrinkage and <br />temperature re1nforcement (see Section 2607(n), 1973 <br />U.D.C.). <br /> <br />.. (b) Beams and Girders (Minimum seismic ties). Members <br />framing into columns shall be provided with a minimum <br />of two #5 bars, top and bottom, continuous throughout <br />their length. These bars shall lap at least 32 dia- <br />meters with the reinforcement provided in adjacent spans. <br />Splices shall not be located within the column, or with- <br />in twice the member depth from the column face. At <br />exterior supports, this minimum reinforcement shall <br />anchor into the support with a 32-diameter embedment or <br />shall extend to the far face of support and terminate <br />in a 90 degree standard hook. The minimum reinforcement <br />ratio "p" for the required continuous bars, top and <br />bottom, each shall not be less than 100/fy. Vertical <br /> <br />stirrups shall be provided for the full length of the <br />member with the first stirrup located 2 inches from <br />face of support. Spacing of stirrups shall not exceed <br />d/2 for the first 1/6 of the span. Spacing for the <br />remainder of the span shall not exceed "d" or 18 <br />inches. <br /> <br />.. (c) Concrete Joists (one-way and two-way systems). <br />less than 25% of the joists in each direction shall <br />provided, in order to act as "tie members," with at <br />one '5, top and bottom, continuous throughout their <br />length. Joists with this reinforcement shall preferably <br />be those along the column centerline, but in no case <br />located more than 1/4 the slab span on each side of the <br />column centerline. The minimum reinforcement ratio, <br />laps at interior supports, anchorage at exterior supports, <br />for this reinforcement shall be the same as required in <br />sub-paragraph (b) above. <br /> <br />Not <br />be <br />least <br /> <br />.1 (d) Beam, Girder or Joist systems without columns: In <br />framing schemes without columns, at least 25% of the <br />beams, girders, or joists shall comply with paragraph (b) <br />and (c) above. <br /> <br />.1 (e) Slabs. When the minimum required seismic ties <br />(sub-paragraphs (b), (c) and (d)) are not provided by other <br />framing members, at least 25% of the positive reinforcement <br />in the slab shall continue throughout the span, and shall <br />lap with reinforcement of the adjacent spans or anchor at <br />exterior supports as required in sub-paragraph (b) above. <br /> <br />.I(f) Flat Slabs. Top and bottom reinforcing shall be <br />provided in the column strips, continuous throughout <br />their length. The minimum reinforcement shall be at <br />least 25% of the maximum negative reinforcement. This <br />minimum reinforcement shall be provided in both top and <br />bottom of the slab. Laps at interior columns and <br />anchorage at exterior supports for this reinforcement <br />shall be as required in sub-paragraph (b) above.' <br />