Solutions for certain rectangular slabs continuous over flexible ...
Solutions for certain rectangular slabs continuous over flexible ...
Solutions for certain rectangular slabs continuous over flexible ...
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26 ILLINOIS ENGINEERING EXPERIMENT STATION<br />
1 (1 + A) P 7V<br />
M() | - log, coth --<br />
J x=./2 47r a<br />
-- Pv 1+ (1-p)1) v coth-- 2Vv csch--2vv<br />
2a 2a a a<br />
M ] (1 + p) P Vh<br />
=W - Irxr~ onih _ ~/O ~\<br />
J x=a/2 47r " a<br />
Pv P p- (1-)rv-- coth- 2iry<br />
csch<br />
2iy<br />
-- ,<br />
2a 2a a a<br />
M() = 0.<br />
xy I -a/2<br />
The resultant bending moment My in the slab <strong>over</strong> the beam<br />
becomes, when u = a/2 in (32),<br />
] Pv<br />
sinh -<br />
a<br />
sin --<br />
a<br />
M] = -_ - - -(36)<br />
i_0 a 2yrv<br />
cosh - + cosa<br />
2irx<br />
a<br />
7V<br />
rx<br />
Since the corrective twisting moment in the slab <strong>over</strong> the beam is<br />
zero, according to (35), the resultant twisting moment is given completely<br />
by the effect of a concentrated load on the infinitely long slab<br />
without the cross beam. The equation <strong>for</strong> the twisting moment in<br />
the slab <strong>over</strong> the beam is, there<strong>for</strong>e,<br />
cosh - cos -<br />
U ] = 1 (1- ) Pv a a<br />
M \ =M (0 \ =<br />
(37)<br />
,=0o J= 2a 2-v 2x (37)<br />
cosh - + cos -<br />
a<br />
a<br />
Westergaard* gives numerical values and curves obtained from an<br />
*H. M. Westergaard, Computation of Stresses in Bridge Slabs Due to Wheel Loads, Public Roads,<br />
V. 11, No. 1, March, 1930, p. 12-15. See Westergaard's Equation 75, Figures 12 and 14, and Table 5.