USEFUL DATA 



ing to the dimension U, and Tc^^i (^2~q" I at a section in the other direction. The 



limitations of the apportionment of moment between inner section and outer section 

 and between mid-section and colunm-head sections may be the same as for square 

 panels. 



{i) Wall Panels. — The co-efficient of negative moment at the first row of columns 

 away from the wall should be increased 20 per cent over that required for interior 

 panels, and likewise the co-efficient of positive moment at the section half way to the 

 wall should be increased by 20 per cent. If girders are not provided along the wall 

 or the slab does not project as a cantilever beyond the column line, the reinforcement 

 parallel to the wall for the negative moment in the column-head section and for the 

 positive moment in the outer section should be increased by 20 per cent. If the wall 

 is carried by the slab this concentrated load should be provided for in the design of 

 the slab. The co-efficient of negative moments at the wall to take bending in the 

 direction perpendicular to the wall line may be determined by the conditions of re- 

 straint and fixedness as found from the relative stiffness of columns and slab, but in 

 no case should it be taken as less than one-half of that for interior panels. 



(j) Reinforcement. — In the calculation of moments all the reinforcing bars which 

 cross the section under consideration and which fulfill the requirements given under 

 paragraph {I) of this chapter may be used. For a column-head section reinforcing 

 bars parallel to the straight portion of the section do not contribute to the negative 

 resisting moment for the column-head section in question. In the case of four-way 

 reinforcement the sectional area of the diagonal bars multiplied by the sine of the 

 angle between the diagonal of the panel and straight portion of the section under 

 consideration may be taken to act as reinforcement in a rectangular direction. 



{k) Point of Inflection. — For the purpose of making calculations of moments at 

 sections away from the sections of negative moment and positive moment already 

 specified, the point of inflection on any line parallel to a panel edge may be taken as 

 one-fifth of the clear distance on that line between the two sections of negative moment 

 at the opposite ends of the panel indicated in paragraph (e), of this chapter. For slabs 

 having dropped panels the co-efficient of one-fourth should be used instead of one-fifth. 



(I) Arrangement of Reinforcement. — The design should include adequate provision 

 for securing the reinforcement in place so as to take not only the maximum moments, 

 but the moments at intermediate sections. All bars in rectangular bands or diagonal 

 bands should extend on each side of a section of maximum moment, either positive 

 or negative, to points at least twenty diameters beyond the point of inflection as defined 

 herein or be hooked or anchored at the point of inflection. In addition to this provision 

 bars in diagonal bands used as reinforcement for negative moment should extend on 

 each side of a line drawn through the column center at right angles to the direction of 

 the band at least a distance equal to thirty-five one-hundredths of the panel length, 

 and bars in diagonal bands used as reinforcement for positive moment should extend 

 on each side of a diagonal through the center of the panel at least a distance equal to 

 thirty-five one-hundredths of the panel length; and no splice by lapping should be 

 permitted at or near regions of maximum stress except as just described. Continuity 

 of reinforcing bars is considered to have advantages, and it is recommended that not 

 more than one-third of the reinforcing bars in any durecUon be made of a length less 



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