SILO DESIGN A)
Given Data:
Theory to be used: = Janssen's Theory Type of material stored = Clinker Diameter of the silo, D = 30 m Unit weight of material = 1 k>+m3 !ngle of repose, " = 3# Degrees $atio of %ori&ontal to 'erti(al pres) intensity, *h+* -n. Coeff) of fri(tion between material and all, 1 0)#" B)
0)/1 /)/#0
Allowable St Stresses:
or 2rade of (on(rete = 300 or 2rade of steel = 100 4las 4lastiti(( mod modul ulus us of (on( (on(re rete te 4( =1 311 311 5(t= 1)165(u = /0)117 4lasti( m moodulus ooff 8t 8teel 4s 4s = /100000 m9 4s+4( = )3##3
C)
= =
kg+(m/ kg+(m/ kg+( kg+(m/ m/ kg+(m/ kg+(m/
Desi Design gn of Cyli Cylind ndri rica call al alls ls::
%ori&ontal pressure, *h here, n %ydrauli( mean radius, $
=
w$+1AE19ep-91nh+$.F
= = = =
-19sin"+1;sin". 0)/1 D+7 )# m
or different alues of h from top, t op, *h alues are (al(ulated as below: Depth from top, h in m / 7 < 10 1/ 17 1 1< 1 u AnAh+$ 1)< 3)3<1 #)0< )#<< )7<7 11)3< 13)/< 1#)1< 1)0 %ori&ontal *r), *h in k>+m/ 3)< 7)7<#3# 7)# 7)# 7)# 7)# 7)# 7)# 7 ) 8o, ma) hori&ontal pressure in the (ylindri(al portion, *h %oop tension in (ylindri(al wall per meter height, t
= =
7)# <)#1
!rea of hoop reinfor(ement, reinfor(ement, !st !st = ??? mm/ !dopt /0 mm dia) %oops at 1#0 mm (+() is giing !st *roide, ho hoop rein) at bo both inernal @ eternal sides of wa wall, !st
= =
/07 mm/ 71< mm/
Using Using #00 mm thi(k thi(k (ylind (ylindri( ri(al al walls walls)) Tensile stress in in ((oon(), 5( 5(t = t+-!(;mA!st. = 0)17 >+mm/ 'erti(al pressure intensity at a depth, h *
= =
B
0
??? m is, 1 k>+m/
4uialent de depth of of (e (ement = 1)0#733# m 4en 4en tho thoug ughh ther theree is is ??? m dept depthh of of (emen (ement, t, the effe(t effe(tie ie erti erti(al (al load is only due to 1)0# m of (ement) (ement)
>+mm/
k>+m/ k>
!E"ISE
?$4G m depth of (ement (orresponds to a pressure 'erti(al pressure intensity at a depth of ?$4G m is
= = = The remaining ??? H is transferred to the silo walls by fri(tion)
??? k>+m/ 1 k>+m/ and is ??? H of total weight)
or different alues of h from top, *h, t and !st alues are (al(ulated as below: Depth from top, h in m / 7 < 10 1/ 13 1# 1 %or) *ressure, *h in k>+m/ 3)<< 7)7<#3# 7)# 7)# 7)# 7)# 7)# 7)# 7) %oop tension, t in k> #<)/< )0/<03 <)37 <)#7 <)# <)# <)# <)# <)# / %oop 8teel, !st in mm ??? ?DI'+0G ??? ??? ??? ??? ??? ??? ??? Vertical Distribution Steel:
Jinimum area of steel
= 0)/#H of (ross se(tional area = 1/#0 mm/ !dopt 10 mm dia) %oops at 1/# mm (+() towards the top of silo, / is giing !st = /< mm *roide, erti(al rein) at intenal @ eternal sides of wall, !st = 1/# mm/
/1)3< /0)/ 7)
1)00 7) <)# ???
