. , , . 3.57. hef = bef = 350 . l 0/ hef = 3600/350 = 10,3 < 16, , . 3.54 3.58, l 0/ hef > 4.
l 0/ cef = l 0/ hef = 10,3 h = hef = 350 ,
, d e = d e,min = 0,297. , h 2 a 1 = 350 2 22 = 306 [58 < = 76,5 (. . 48)], . 3.63 S S . , , , :
;
.
jl (94), b = 1,0 (. . 16)
Ncr (93),
2 (6 Æ 25),
jl = 0,25 + 0,05 = 0,25 + 0,05 10,3 = 0,764:
h :
, (111),
.
Rb,red . 3.57.
sx = sy = 78,5 2 (Æ 10), nx = ny = 5, lx = ly = 350 Aef = hefbef = 350 350 = 122 500 2 (. . 48),
.
A-VI, . 3.59:
2;
q = 1,6.
. 25 l1 = 2,04, l2 = 0,77, Rsc = 500 , Rs = 815 ,
(108), = xh 0 (110).
(104) w. 10 mxy = 10 0,0173 = 0,173 > 0,15, d2 = 0,15, w = 0,85 0,008 Rb + d2 = 0,85 0,008 20 + 0,15 = 0,84 £ 0,9.
, . 3.61 3.65, a n, a s, yc, Rb = Rb,red = 34,3 ; ssc,u = 380 + 1000 d3 = 380 + 1000 0,54 = 920 < 1200 Rsc = Rsc,red = 742 :
xR Rs 0,8 Rs :
. . (110a) ;
;
. . .
N = 5500 ( gf = 1,0), , . 3.60, Rb = Rb,ser = 29 , Rs = Rs,ser = 980 , Rsc = 400 , ssc,u = 400 , w = 0,85 0,006 Rb,ser = 0,85 0,006 29 = 0,679 , . . b = h = 400 , a = a¢ =41 + 25 = 66 , h 0 = 400 66 = 334 .
|
|
Ncr (93), l 0/ h = 3600/400 = 9, e 0/ h = 13,3/400 = 0,033, de,min = 0,5 0,01 0,008 Rb,ser = 0,5 0,01 9 0,008 29 = 0,178 > e 0 /h, . . de = de,min = 0,178.
jl N Nl gf = 1,0, . .
jl = 1 + 0,7 = 1,7;
:
.
:
;
. . .
33. : ¾ . 49; 30 (Eb = 2,9 104 ; Rb = 19 gb 2 = 1,1); -III (Rs = Rsc = 365 ); As = A¢s = 5630 2 (7 Æ 32); : Nl = 2000 , Ml = 2460 ͷ; N = 2500 , = 3700 ͷ; : l 0 = 16,2 , l 0 = 10,8 ; l = 10,8 .
.