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Budapest University of Technology and EconomyFaculty of Civil EgeneeringDepartment of Structural Egineering
DESIGN OF TWO WAY SPANNING FLOOR-SLAB
Manuel v1.11
Koris, Kálmán Dr. Ódor, PéterPéczely, Attila Dr. Strobl, András Dr. Varga, László
Budapest, 2005.
1 It is not a final version. It could be loaded from http:/www.vbt.bme.hu/oktatas/vb2 website
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Content
1. Sizing .....................................................................................................................................3
1.1. Data ..................................................................................................................................31.2. Sizing of beams ................................................................................................................ 4
1.3. Sizing of the thickness of the slabs L1 and L2.................................................................. 4
1.3.1. The effective depth .................................................................................................... 4
1.3.2. Cover ......................................................................................................................... 4
1.3.3. Appropriate cover ...................................................................................................... 4
1.3.4. The final thickness of the slab: ..................................................................................5
1.4. Materials .......................................................................................................................... 5
1.5. The characteristic value of loads...................................................................................... 5
1.6. The design (ultimate) load: .............................................................................................. 5
1.7. Approximate analysis of the thickness of slab.................................................................5
1.8. L1and L2 slabs .................................................................................................................. 61.9. Spans ................................................................................................................................6
2. Calculation of the moments................................................................................................. 8
2.1. The maximum positive and negative moments ............................................................... 8
2.2. Calculating of moment maxm in direction x and y at point ..........................................9
2.3. Calculating of maxm moment in x and y direction in point ...........................................9
2.4. Negative bending moment in point ............................................................................. 9
2.5. Bending moments in practice......................................................................................... 10
2.6. Bending moments
max, xm és
max, ym in point of slab L1 ............................................ 10
2.7. Bending moment maxm in point (above the support)............................................. 11
2.8. Bending moment maxm in point (above the support)............................................. 12
2.9. The bending moment diagram .......................................................................................13
2.10. Redistribution of moments........................................................................................... 15
2.11. The modified bending moment diagram...................................................................... 16
3. Analysing of sections ..........................................................................................................17
3.1. Effective slab thickness and the area of steel required .................................................. 17
3.2. The moment of resistance .............................................................................................. 18
3.3. The minimal reinforcement required ............................................................................. 18
3.4. The anchorage length..................................................................................................... 18
4. Rules of reinforcement....................................................................................................... 19
5. 5. The drawing .................................................................................................................... 19
6. A törteher számítása ........................................................................................................ 20
6.1. Energia módszer.............................................................................................................20
6.2. Egyensúlyi módszer ....................................................................................................... 22
7. APPENDIX ......................................................................................................................... 24
7.1. Bar s’s tables for moments of two way spanning slab .................................................. 24
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1. Sizing
1.1. Data
The span can be calculated according to the data sheet. The width of the beam G 2 in direction
y approximately is113
2
2
1 0 y
x
lb
. From this value the length of the span can be
determined in x direction:
mml
lcl
x
x y
38028011
05,1
3
2
2
1 b
m2,70,62,1
10x
1020
say: bx =350 mm.
The span (in y direction) of the two way spanning slab can be calculated using the ratio given
on data sheet (in case of l0y/l0 x = 1,2):
80,110,635,045,5
m45,51,1
0,6
1
1020
l
c
ll x
x
210
0
x
y
l
l
h 1
l0 x,1 l0 x,2
x
y
b 1
l 0 y
r
h2
h 2
h
30b2 30
l
h
l x,2 l x,1
h1
b 1
L2 L1
O1
O1
G1 G1
G1 G1
G2
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1.2. Sizing of beams
In a case of usual load and loaded area for a beam has a hight of (acc. of a rule of thumb):
mmmml
h x
x 5505,54511
00,6
1210
mmmml
h y y 6505,654
11
20,7
1210
mmmmh
b y
x 3504,3827,1
650
25,1
mmmmh
b x y 3005,323
7,1
550
25,1
Remark: Size b x of beam in y direction should be calculated from h y , and b y of beam in x direction should becalculated from h x.
1.3. Sizing of the thickness of the slabs L1 and L2.
1.4. The effective depth
4020 short
slab
ld ; but the minimum thickness is d min=50 mm.
mmmmd slab 1800,18035
0,6·05,1
1.5. Cover
minimum cover (1. class ):
mm32hamm][
mm32hamm15min. c
increasing due to inaccuracy: 5 mm c 10 mm
For the lower mesh c = 5 mm could be recomended, for the upper mesh c = 10 mm because of the tread down during assembling.
1.6. Appropriate cover
For the lower layer of reinforcement:
cl = nom. c = min. c + c = 15 + 5 = 20 mm
For the upper layer of reinforcement:
cu = nom. c = min. c + c = 15 + 10 = 25 mm
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1.7. The final thickness of the slab:
mm210hmm2072
1420180
2
acd h
1.8. Materials
Grade of concrete: C20/25 f ck = 20,0 N/mm2 safety factor c=1,5
E cm = 28,8 kN/mm2
Grade of steelbar: B 60.40 f yk = 400 N/mm2 safety factor s=1,15
1.9. The characteristic value of loads
The masses: (floor layers)
Materials thickness
[mm]
density [kN/m3] dead load (gi)
[kN/m2]
1. tiling 10 23,00 0,23
2. embedding plaster 20 22,00 0,44
3. pure concrete 40 22,00 0,88
4. technological isolation - - -
5. Nikecell foamlayer 60 1,50 0,09
6. r.c. slab 210 25,00 5,25
7. plaster 15 20,00 0,308. partition wall 1,50
dead load: Gk = gi = 8,69 kN/m2
live load: Qk = 5 kN/m2
1.10. The design (ultimate) load:Design load: Gd + Qd = G·Gk + P·Qk , where are the safety factors 1,35 and 1,5 for the
dead and the live loads , respectively.
Gd + Qd = 1,35·8,69 + 1,5·5 = 19,23 kN/m2
1.11. Approximate analysis of the thickness of slabApproximate moment at the support:
m
kNm52,54
14
00,605,1·23,19
14
)05,1·(22
0
max
xd d lQGm
In design state for slab c 0,2 could be recommended
2mm
N
33,135,1
20
ck
cd
f
f
d
cl Ø/2
cu
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The ultimate moment of resistance for a unit wide strip:
)2
(1000maxc
cc
ck Rd
d d d
f mm
From the equation we can obtain the effective depth of the section:
2
2,01·2,0201000
5,110·52,54
21·1000
6max
ccck
c
f
md
d = 150,1 mm < d slab = 150 mm, so the overall thickness of the slab mmh 210 is suitable.
1.12. L1and L2 slabs
m x = ?
m y = ?
in points
1, 2 and 3
1.13. Spans
The spans l x and l y (for the accurate analysis) can be determined: the clear span l0 x, l0 y should
be increased by 1/3·t 1/2·t at exterior span and by 1/2·t at interior span, where t is the length of the support.
m275,6
2
35,01,000,6
23
cm30101 x
x x
bll
l y
l x2 l x1
12
3
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m725,52
35,01,045,5
23
cm30202
x x x
bll
m50,730,020,7
2
20 y y y
bll
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2. Calculation of the moments(Using elastic theory of slabs)
2.1. The maximum positive and negative moments
Generally the maximum moments can be obtained if the arrangement of the loads is:
a.) "Gd " (dead load) is all over slabs
b.) "Qd " (imposed load) is arranged according to the influence line theory on
some slabs.
This is an accurate method but an approximate method can be used if the ratio between the
spans is 25,18,0 b
j
l
l. According to the method the total (ultimate) load should be devided
into two parts:
q’ is UDL load in every fields
q’’ is positive or negative alternating UDL load in every fields, respectively.
- UDL substituting load is acting totally and its value is:
2' k
Qk G
QGq
- alternating load:
2" k
Q
Qd
Gd
= +
Qd /2 -Qd /2 +Qd /2
Q d
1+
If the span condition lr /ll mentioned above is true, the rotations of adjacent spans at thecommon support are almost equel, and it is zero. Thus the ends of the spans may be supposed
as fixed ones for both spans at the adjacent section, so that the slabs can be analysed
separately. The value of rotation of adjacent spans due to alternating loads at the common
support is almost the same but the direction is opposite. That is why we can suppose a hinged
support for the end conditions of the slabs.
The final moment will be the algebraical sum of the moments due to the load q’ and q’’.
"'max qq mmm
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2.2. Calculating of moment maxm in direction x and y at point
?1
max m
- q' has to be put totally,
- q'' has to be arranged alternally!
maxm = mq' ± mq"
2.3. Calculating of maxm moment in x and y direction in point
?1
max m
The method of calculation is the same as at point 2.2 except instead of using lx1 the lx2 should
be used!
2.4. Negative bending moment in point
?2
max m
On the shaded area q' should be placed totally downward, the remained part should be loaded
by ±q'' . Take care of the edge conditions!
In case of non-equal l xi values both slab should be analysed.
Qd
Gd
=
Qk /2
Q d
- Q d / 2
+ Q d / 2
Q d
G d
2
+
Q d / 2
L1 L1 +
load: q' load: q''
L1 L1 L1 L1 + +ill.
load: q' load: q''
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In the point the bending moments may be not equal because of the different lx1 and lx2. In
that case the out-of-balance bending moment should be redistributed in the ratio of the
relative stiffness of the slabs (in the ratio 1/lx1 and 1/lx2, respectively)
The bending moment coefficients are given in Tables Bar s (see attached!)
1 2 3 4 5 6
1 2 3 4 5 6
L1: 837,05,7
275,6
y
x
l
l
L2:
763,05,7
725,5
y
x
l
l
2.5. Bending moments in practice(using the Tables)
2.6. Bending moments max, xm és
max, ym in point of slab L1
2m
kN48,15
2
5·5,169,8·35,1
2··' k
Qk G
QGq
2m
kN75,3
2
5·5,1
2·" k
QQq
l y
l x1
L10,837
0,0298 0 , 0
1 8 5
L10.837
0,0571 0 , 0
2 9 7
+
q' q"
Tab. 1.11 Tab. 1.7
"0571,0'0298,02
1
1
max, qqlm x x
m
kNm
59,26)75,3·0571,048,15·0298,0·(275,621
max,
xm
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"0297,0'0185,021
max, qqlm y y
m
kNm37,22)75,3·0297,048,15·0185,0·(5,7 21
max, ym
2.7. Bending momentmaxm in point
(from L1, above support)
L10,837
-0.0762
l y
l x
+
q' q"
L11.195
Tab. 1.11 Tab. 1.8
-0.0977
As mentioned above that bending moment should be calculated in slab L1 and L2,
respectively. The bending moments should be finally equalised. Pay attention, the Table 1.8
refers to the slab with one short continuous edge. In our project the slab has one long
continuous edge, so the lx/ly ration should be exchanged!
)"·0977,0'·0762,0·(2
1
2
max, qqlm x x
m
kNm87,60)75,3·0977,048,15·0762,0·(275,6 22
max,
xm
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2.8. Bending moment maxm in point (above the support)
L10.837
l y
l x
+
q' q"
L10.837
Tab. 1.8Tab. 1.11
- 0 , 0 5
0 2
- 0 , 0 6
8 9
)"·0689,0'·0502,0·(23
max, qqlm y y
m
kNm25,58)75,3·0689,048,15·0502,0·(9,7 23
max,
ym
2.9. Bending moments max, xm és
max, ym in point of slab L2
"0654,0'0350,022
4max, qqlm x x
m
kNm80,25)75,3·0654,048,15·0350,0·(725,5 24
max, xm
"0240,0'0151,024
max, qqlm y y
m
kNm21,18)75,3·0240,048,15·0151,0·(5,7 24
max, ym
2.10. Bending moment maxm in point (from L2, above support)
)"·1036,0'·0854,0·(22
2max, qqlm x x
m
kNm06,56)75,3·1036,048,15·0854,0·(275,6 22
max, xm
2.11. Bending moment maxm in point (above the support)
)"·0609,0'·0438,0·(23
max, qqlm y y
m
kNm98,50)75,3·0609,048,15·0438,0·(9,7 23
max, ym
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2.12. Balancing of moment in point
There is an out-of-balance bending moment above the support.
m
kNm
87,602
1max,,
L xm
m
kNm06,562
2max,, L xm
m
kNm81,406,5687,602
xm
on the slab L1
m
kNm29,281,4
725,5
1
275,6
1275,6
1
11
1
2
21
12
1
x
x x
x x m
ll
lm
on the slab L2
m
kNm52,281,4
725,5
1
275,6
1
725,5
1
11
1
2
21
22
2
x
x x
x x m
ll
lm
The balanced moment in point
m
kNm58,5852,206,562
, new xm
and the positive midfield moments
m
kNm74,27
2
29,259,26
2
2
11
max,
1
max,,
x xnew x
mmm
m
kNm54,24
2
52,280,25
2
2
24
max,
4
max,,
x
xnew x
mmm
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2.13. The bending moment diagram
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2.14. Redistribution of moments
As the ratio of
m
m is disadvantageous in reinforcing, a redistribution of bending moments
may be made. The redistribution may be appplied, if
the resultant moment is in equalibrium with the loads applied,
for the ratio of the spans it is true that 5,02 b
j
l
l;
d
x 25,144,0 , if the grade of concrete is not greater than C35/40;
7,0 using high ductility steel, i.e 5ud % ( ud fracture strain);
85,0 using normal ductility steel, i.e. 5,2ud %;
where.
.
nondistr
distr
m
m ;
x: depth of compression zone after redistribution;
d : effective depth of the section.
An economical reinforcement can be designed, if 5,1
m
m, taking the conditions into
consideration given above.
As the sum of the bending moments must not be changed therefore
mmmm ecec
Moment redistribution for m x (in slab L1):
m
kNm53,34
5,2
58,5874,27
5,11
1
,
mmm xec
m
kNm80,5153,345,15,12
, ec xec mm
85,088,058,58
80,512
,
m
m xec OK.
Moment redistribution for m y (in slab L1):
m
kNm25,32
5,11
25,5837,221,
yecm
m
kNm38,4825,325,13,
yecm
85,083,025,58
38,48 , it is not OK.
As the condition of 85,0 should be fulfilled:
m
kNm51,4925,5885,085,03, mm yec
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Of course the sum of the positive and negative moments after the redistribution must not be
changed (equalibrium condition!), from where we get:
m
kNm11,3151,4925,5837,222,
ec yec mmmm
2.15. The modified bending moment diagram
Because of the partial fixing of the outer support, the 25 % of the midfield moment should betaken into calculation on this support.
According to the EUROCODE:
m
kNm98,693,2725,0
25,0 4
2,
xecleft mm
m
kNm63,853,3425,0
25,0 1
1,
xecright mm
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3. Analysing of sections
As the bending moment is bigger in the shorter direction, the lower (layer) reinforcement is
running in the shorter direction.
3.1. Effective thickness of slab and area of steel required
The effective slab thickness would be different in x és y direction for the positive and negative
bending moments xm ;
xm ; ym ;
ym , respectively.
mm1832
1420210
2:
a x x chd m for
mm1782
1425210
2:
f x x chd m for
mm16914183: x y y d d m for
mm16414178: x y y d d m for
secti
onm x( y)
[kNm/m]d x( y)
[mm] xc
[mm]as,cal
[mm2/m]as,provided as
[mm2/m]
0’x -8,63 178
1x +34,53 183
2x -51,80 178
4x +27,93 183
0’’x -6,98 178
1y +31,11 169
3y -49,51 164
4y 169
5y 164
Calculate xc from this equation
2
ccd c
xd f xbm
mmb 1000
Then
yd calscd c f a f x ,1000
yd
cd ccals f
f xa
1000,
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3.2. The moment of resistance
km as
[mm2/m]
xc [mm]
m Rd [kNm/m]
m Rd > mSd m Rd
mSd >1
0’x
1x
2x
4x
0’’x
1y
3y
4y
5y
cd c yd s f xb f a 0ccd
yd sc x
f b
f a x
2
ccd c Rd
xd f xbm
3.3. The minimal reinforcement required
d b f
d b
a yk s
0015,0
6,0
maxmin, ( f yk in [N/mm2
])
cs Aa 04,0max,
3.4. The anchorage length
The basic value:bd
yd b f
f l
4 (where f bd is taken from Table below)
f ck 12 16 20 25 30 35 40 45 50Smooth
surface
0,9 1,0 1,1 1,2 1,3 1,4 1,5 1,6 1,7
ribbed
1,6 2,0 2,4 2,8 3,2 3,6 3,9 4,2 4,5
Anchorage length required: min,
,
,
b provs
recsbsb l
A
All
s = 1 in case of smooth surface steel
As,rec = area of steel required
As,prov = area of steel providedThe minimal anchorage length:
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103,0min, bb ll tension steeel bars
mm1006,0min, bb ll compression steel bars
The anchorage length of bend-up bars for shear resistance:
In tension zone.: 1,3
lb,net In compression zone: 0,7lb,net
4. Rules of reinforcement
Maximal distance between bars:
main bars: mm3505,1 h (h: depth of slab)
distributors: mm4005,2 h
At least the half of midfield reinforcement should be let to the support and fixed there
At pinned support a reinforcement should be provided
5. The drawing Signing of bars
The place of the bar should be given from the moulding
Bottom view !!! (the section is taken below the slab, seeing in a mirror)
Do not use many types of bars, or diameters next to each other
Use stays (supporting reinforcement)!
In notes indicate!:
grades of materials (concrete, steelbars);concrete cover;
characteristic value of imposed load;
and any other data, if there are Schedule of bars
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6. A törteher számítása
6.1. Energia módszer
A kinematikailag lehetséges tör terhet a küls és bels munkák egyenlsége alapján lehet
meghatározni.
Lk = Lb
Vegyünk fel egy lehetséges törésképet a lemezek törésvonal elmélete alapján. Nyomatéki paraméterként a hosszabbik oldalhoz tartozó, m pozitív nyomatékot választjuk. A rövidebbik
irányban fellép nyomatékot -val való szorzással, a támasznyomatékokat 1 4 szorzóksegítségével számíthatjuk az m nyomatékból. Geometriai paraméterként a törésvonalak
metszéspontját meghatározó 1, 2 és tényezk vehetk fel.
2 = 4 (a szimmetriából adódóan)
1 = 1 - 2
l x = 5,6 m l y = 7,9 m 710 ,l
l
y
x
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m
kNm8336 ,m (lásd 3.2.)
m
kNm31,93 m 87,0
m
kNm66181 ,m
51,01
m
kNm614742 ,m m
30,142
m
kNm46553 ,m
51,13
A p teher által az elmozduláson végzett küls munka a töréskép által meghatározott térfogatalapján számítható.
12
212
3
11
22
3
11
22
3
11
2
21 y x y x y x y xk k
llllllll p L
236
y xk k
ll p L
A bels munka a nyomatéknak a törésvonalak menti elforduláson végzett munkájával
egyenl.
21
11
2
111
2
2
13
21
21
y x
x y x y y x x x yb
llm
llm
llm
llm
lllm L
mmmmmm
Lb 21
2
3
1
22111
49,1131
33,781
20,1301
21
b L
A küls és bels munkák egyenlsége alapján ( Lk = Lb):
49,11333,7820,130
2337,721
k p
12 1
A tör teher tehát két paraméter függvény, amikbl a szélsérték parciális deriválással
kapható.
, f p 1
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Two way spannig slab - v1.1
22
37,7·3·2··1·
·49,113··20,13033,78·20,130·49,113 2
k p 211 ,
0
0
p
p
A deriválást elvégezve: 563,01 , 436,02 , 424,0
A kapott értékeket behelyettesítve a fenti egyenletbe megkapható pk értéke:
2m
kN74,42k p
6.2. Egyensúlyi módszer
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Two way spannig slab - v1.1
23
Ez is törési határállapot-vizsgálat. A kinematikai tételen alapszik. (A feladatban taláncélravezet bb!) A küls terhek nyomatékának és a bels nyomatékok egyensúlyának
felírásából számítható a határer .
és lemezdarab azonos
3
2
2
22
2
y x x
ll pmml
lemezdarabra:
32
22
2122
22
2
1 x y x x y
y
lllll pmml
lemezdarabra:
322
2
2111
22
13 x y x x y y
lllll pmml
ismeretlenek: p, 1 ,
adott: 3 egyenlet
56,01 , 44,02 , 42,0 ,2m
kN74,42 p
22 m
kN45,17
m
kN74,42 d p p
145.2
45,17
74,42
d p
p Megfelel!
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Design of two way spanning slab
7. APPENDIX
7.1. Bars’s tables for moments of two way spanning slab
Tab. 1.7 =0,15
ws M xs M ys
0,50 0,1189 0,0991 0,0079
0,55 0,1101 0,0923 0,0103
0,60 0,1015 0,0857 0,0131
0,65 0,0931 0,0792 0,01620,70 0,0851 0,0730 0,0194
0,75 0.0777 0,0669 0,0230
0,80 0,0708 0,0611 0,0269
0,85 0,0644 0,0557 0,0307
0,90 0,0584 0,0507 0,0344
0,95 0,0529 0,0462 0,0383
1,00 0,0476 0,0423 0,0423
1,10 0,0390 0,0353 0,0500
1,20 0,0320 0,0293 0,0575
1,30 0,0262 0,0244 0,0644
1,40 0,0216 0,0204 0,0710
1,50 0,0179 0,0173 0,0772
1,60 0,0149 0,0146 0,0826
1,70 0,0124 0,0124 0,0874
1;80 0,0105 0,0107 0,0916
1,90 0,0088 0,0091 0,0954
2,00 0,0074 0,0079 0,0991
q· a4
E· h3 q· a2 q· b2
Tab. 1.8 =0,15
ws M xs M ys M yvs
0,50 0,1087 0,0908 0,0084 -0,0305
0,55 0,0981 0,0826 0,0109 -0,0362
0,60 0.0881 0,0747 0.0135 -0,0421
0,65 0,0786 0,0670 0,0162 -0,04790,70 0,0698 0,0599 0,0192 -0,0537
0,75 0,0618 0,0533 0,0221 -0,0594
0,80 0,0544 0,0472 0,0249 -0,0650
0,85 0,0479 0,0417 0,0277 -0,0703
0,90 0,0421 0,0369 0,0304 -0,0750
0,95 0,0370 0,0327 0,0330 -0,0797
1,00 0,0326 0,0291 0,0354 -0,0840
1,10 0,0253 0,0228 0,0399 -0,0917
1,20 0,0197 0,0180 0,0438 -0,0980
1,30 0,0155 0,0143 0,0471 -0,1032
1,40 0,0123 0,0115 0,0500 -0,1075
1,50 0,0099 0,0094 0,0524 -0,1109
1,60 0,0079 0,0076 0,0544 -0,1136
1,70 0,0063 0,0062 0,0561 -0,1160
1,80 0,0052 0,0052 0,0575 -0,1184
1,90 0,0043 0,0044 0,0586 -0,1203
2,00 0,0036 0,0037 0,0594 -0,1213
q· a4
E· h3 q· a2 q· b2 q· b2
a y
M x b M y s
xq
q
x=0 x=a
y = 0
y = b
=ab =
ab
M xbs = · M yvs
a y
q M x b M y s
xq y = 0
y = b
x=0 x=a
M xb M y v
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Two way spannig slab - v1.1
25
Tab. 1.9 =0,15
ws M xs M ys M yvs
0,50 0,0990 0,0835 0,0088 -0,0297
0,55 0,0872 0,0738 0,0113 -0,0350
0,60 0,0759 0,0647 0,0137 -0,0400
0,65 0,0657 0,0563 0,0166 -0,0450
0,70 0,0565 0,0489 0,0187 -0,0497
0,75 0,0484 0,0423 0,0212 -0,0540
0,80 0,0414 0,0363 0,0233 -0,0578
0,85 0,0355 0,0313 0,0254 -0,0612
0,90 0,0305 0,0270 0,0274 -0,0644
0,95 0,0262 0,0232 0,0292 -0,0677
1,00 0,0225 0,0201 0,0309 -0,0699
1,10 0,0167 0,0151 0,0335 -0,0741
1,20 0,0126 0,0113 0,0357 -0,0770
1,30 0,0096 0,0088 0,0374 -0,0793
1,40 0,0073 0,0068 0,0386 -0,0811
1,50 0,0057 0,0053 0,0396 -0,0815
1,60 0,0045 0,0042 0,0404 -0,0825
1,70 0,0036 0,0034 0,0410 -0,0830
1;80 0,0029 0,0028 0,0414 -0,0832
1,90 0,0023 0,0023 0,0416 -0,0833
2,00 0,0018 0,0019 0,0417 -0,0833
q· a4
E· h3 q· a2
q· a2
q· b2
Tab. 1.10
=0,15
ws M xs M xvmin M ys M yvmin
0,50 0,0549 0,0570 -0,1189 0,0040 -0,0205
0,55 0,0520 0,0543 -0,1148 0,0054 -0,0249
0,60 0,0490 0,0514 -0,1104 0,0072 -0,0294
0,65 0,0458 0,0483 -0,1057 0,0092 -0,0341
0,70 0,0425 0,0451 -0,1008 0,0114 -0,0390
0,75 0,0393 0,0418 -0,0957 0,0139 -0,0442
0,80 0,0361 0,0385 -0,0905 0,0164 -0,0496
0,85 0,0330 0,0354 -0,0852 0,0191 -0,0548
0,90 0,0301 0,0324 -0,0798 0,0217 -0,0598
0,95 0,0273 0,0295 -0,0745 0,0243 -0,0648
1,00 0,0246 0,0269 -0,0699 0,0269 -0,0699
1,10 0,0201 0,0221 -0,0608 0,0319 -0,0787
1,20 0,0164 0,0182 -0,0530 0,0365 -0,0869
1,30 0,0133 0,0148 -0,0462 0,0406 -0,0937
1,40 0,0108 0,0122 -0,0405 0,0442 -0,0993
1,50 0,0089 0,0100 -0,0358 0,0473 -0,1041
1,60 0,0072 0,0081 -0,0317 0,0499 -0,1082
1,70 0,0059 0,0066 -0,0282 0,0521 -0,1116
1,80 0,0048 0,0055 -0,0252 0,0540 -0,1143
1,90 0,0040 0,0046 -0,0226 0,0556 -0,1167
2,00 0,0034 0,0040 -0,0205 0,0570 -0,1189
q· a4
E· h3 q· a2
q· a2
q· b2
q· b2
=ab
M x0s = M xbs
M xbs = · M yvs
a y
q M x b M y s
xq y =
0
y = b
x=0 x=a
M xb M y v
M x0 M y v
=ab
M xbmin = · M yvmin
M y0min = · M xvmin
a y
q M x b M y s
xq y
= 0
y = b
x=0 x=a
M xbmi M y v m i
M xvmin
M y 0 m i
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Two way spannig slab - v1.1
Tab. 1.11 =0,15
ws M xs M xvs M ys M yvmin
0,50 0,0528 0,0550 0,1135 0,0045 0,0203
0,55 0,0489 0,0514 0,1078 0,0062 0,0247
0,60 0,0450 0,0476 0,1021 0,0081 0,0291
0,65 0,0411 0,0436 0,0964 0,0101 0,0336
0,70 0,0373 0,0398 0,0906 0,0122 0,0381
0,75 0,0336 0,0359 0,0845 0,0145 0,0427
0,80 0,0300 0,0323 0,0881 0,0169 0.0471
0,85 0,0266 0,0289 0,0720 0,0191 0,0513
0,90 0,0236 0,0257 0,0661 0,0211 0,0551
0,95 0,0209 0,0228 0,0603 0,0232 0,0586
1,00 0,0184 0,0202 0,0546 0,0252 0,0617
1,10 0,0142 0,0158 0,0467 0,0287 0,0676
1,20 0,0110 0,0123 0,0399 0,0316 0,0722
1,30 0,0086 0,0096 0,0341 0,0340 0,0757
1,40 0,0068 0,0075 0,0293 0,0359 0,0782
1,50 0,0054 0,0060 0,0254 0,0374 0,0800
1,60 0,0043 0,0048 0,0221 0,0386 0,0814
1,70 0,0034 0,0039 0,0193 0,0395 0,0825
1;80 0,0027 0,0031 0,0171 0.0402 0,0834
1,90 0,0022 0,0026 0,0154 0,0408 0,0342
2,00 0,0018 0,0022 0,0141 0,0412 0,0847
q· a4
E· h3 q· a
2
q· a
2
q· b
2
q· b
2
Tab. 1.12
=0,15
ws M xs M xvs M ys M yvmin
0,50 0,0296 0,0405 0,0833 0,0024 0,0143
0,55 0,0286 0,0394 0,0817 0,0033 0,0172
0,60 0,0275 0,0378 0,0794 0,0046 0,0206
0,65 0,0261 0,0360 0,0767 0,0061 0,0242
0,70 0,0246 0,0339 0,0737 0,0079 0,0280
0,75 0,0231 0,0315 0,0704 0,0098 0,0320
0,80 0,0214 0,0293 0,0668 0,0103 0,0360
0,85 0,0196 0,0269 0,0631 0,0139 0,0400
0,90 0,0180 0,0247 0,0593 0,0160 0,0440
0,95 0,0164 0,0224 0,0554 0,0181 0,0480
1,00 0,0149 0,0202 0,0515 0,0202 0,0515
1,10 0,0121 0,0164 0,0449 0,0242 0,0585
1,20 0,0098 0,0131 0,0388 0,0287 0,0643
1,30 0,0078 0,0105 0,0336 0,0306 0,0690
1,40 0,0063 0,0084 0,0291 0,0332 0,0728
1,50 0,0051 0,0066 0,0254 0,0353 0,0757
1,60 0,0041 0,0053 0,0223 0,0369 0,0779
1,70 0,0033 0,0042 0,0198 0,0383 0,0797
1,80 0,0027 0,0035 0,0176 0,0392 0,0812
1,90 0,0022 0,0028 0,0158 0,0399 0,0824
2,00 0,0018 0,0024 0,0143 0,0405 0,0833
q· a4
E· h3 q· a
2
q· a
2
q· b
2
q· b
2
=a
b
M xbs = M x0s M yas = M y0s
M x0s = · M yvs
M y0s = · M xvs
a y
q M x b M y s
xq y =
0
y = b
x=0 x=a
M xbmi M y v m i
M x0m M y v m i
M xvs
M y a s
=a
b
M x0min = M xbmin
M x0min = · M yvmin
M yas = · M xvs
q
a y
q M x b M y s
x y = 0
y = b
x=0 x=a
M xbs M y v s
M x0s M y v s
M xvs
M y a s
M xvs
M y 0 s