CORRUGATED BAR COMPANY, INC. 



and reinforcement being made according to the assumptions specified iii this report 

 and no change being made in the vahies of the working stresses ordinarily used. Ac- 

 cordingly, the values of the moments which are recommended for use are somewhat 

 less than those derived by analysis. The values given may be used when the column 

 capitals are round, oval, square or oblong. 



(e) Names for Moment Sections. — For convenience, that portion of the section 

 across a panel along a line midway between columns which lies within the middle two 

 quarters of the width of the panel {HI, Fig. 11), will be called the inner section, and 

 that portion in the two outer quarters of the width of the panel {GH and IJ, Fig. 11) 

 will be called the outer sections. Of the section which follows a panel edge from column 

 capital to column capital and which includes the quarter peripheries of the edges of 

 two column capitals, that portion within the middle two quarters of the panel width 

 {CD, Fig. 11) will be called the mid-section, and the two remaining portions {ABC 

 and DEF, Fig. 11), each having a projected width equal to one-fourth of the panel 

 width, will be called the column-head sections. 



(/) Positive Moment. — For a square interior panel, it is recommended that the posi- 

 tive moment for a section in the middle of a panel extending across its width be taken 



1 / 2c\2 

 as— wZIZ— — j • Of this moment, at least 25 per cent should be provided for in the 



inner section; in the two outer sections of the panel at least 55 per cent of the specified 



moment should be provided for in slabs not having dropped panels, and at least 60 



per cent in slabs having dropped panels, except that in calculations to determine 



necessary thickness of slab away from the dropped panel at least 70 per cent 



of the positive moment should be considered as acting in the two outer 



sections. 



{g) Negative Moment. — For a square interior panel, it is recommended that the 



negative moment for a section which follows a panel edge from column capital to 



column capital and which includes the quarter peripheries of the edges of the two 



column capitals (the section altogether forming the projected width of the panel) be 



1 / 2c\2 

 taken as —wl i I— -^j . Of this negative moment, at least 20 per cent should be 



provided for in the mid-section and at least 65 per cent in the two column-head sec- 

 tions of the panel, except that in slabs having dropped panels at least 80 per cent of 

 the specified negative moment should be provided for in the two column-head sections 

 of the panel. 



{h) Moments for Oblong Panels. — When the length of a panel does not exceed the 

 breadth by more than 5 per cent, computation may be made on the basis of a square 

 panel with sides equal to the mean of the length and the breadth. 



When the long side of an interior oblong panel exceeds the short side by more than 



one-twentieth and by not more than one-third of the short side, it is recommended that 



1 / 2c\2 

 the positive moment be taken as :^wh I ^i~ o" I on a section parallel to the dimension 



1 / 2c\2 

 ^2, and— wZil/2— o~) on a section parallel to dimension Zi; and that the negative 



moment be taken as rzwh ( ^1 ~ o~ I on a section at the edge of the panel correspond- 



206 



