Tải bản đầy đủ (.pdf) (22 trang)

Kiểm toán cống hộp 4x4m bằng phần mềm midas civil

Bạn đang xem bản rút gọn của tài liệu. Xem và tải ngay bản đầy đủ của tài liệu tại đây (769.34 KB, 22 trang )

Project :
Item

Box Culvert 4x4M

CALCULATION SHEET OF BOX CULVERT ACCORDING TO 22TCN272-05
B CALCULATION
I. LOADS

1 Input
Kind of box Culvert

Explanation
=

Value
Single

Pavement layer thickness dađ(m)
Thickness of filling layer above the top of the box culvert H (m)

=
=

0.80
0.83

Length of box culvert segment Ltt (m)
Inside with of box culvert b (m)
Inside height of box culvert h (m)


=
=
=

1.00
4.00
4.00

Thickness of top slab dbn(m)

=

0.35

Thickness of wall dw (m)

=

0.35

Thickness of bottom slab dbđ (m)

=

0.35

Heigth of water calculation h1 (m)

=


4.00

Density of pavement structure γađ (T/m3)

=

2.40

Density of backfill γs (T/m3)

=

1.80

Density of water γw (T/m3)

=

1.00

Density of concrete γc (T/m3)

=

2.50

Angle of internal friction of soil ϕf (degree)
Gravitational acceleretion g (m/s2)

=

=
=
=

30
9.81
2.00
1.00

Number of caculated lanes (count for 1/2 box)
Multiple presence factor m
Width of box culvert Bc (m)

Bc = 2 x b + 3 x dw

=

4.70

Height of Box culvert Hc (m)

Hc = h + dt + db

=

4.70

Caculated width of box culvert btt (m)

btt = 2 x b + 2 x dw


=

4.35

Calcualted heigth of box culvert htt (m)
Self weigth of box culvert Pb (T)

htt = h + dn / 2 + dñ / 2
Pb = γc x (h x 2 x dw + Bc x (dn + dñ))

=
=

4.35
15.23

k0 = 1 - sinϕf

=

0.50

At-rest pressure coefficent k0
2 Dead loads

Wañ = γañ x dañ

=


1.92

We = γs x Ltt x H

=

1.49

Max horizontal pressure PA (T/m2)

PA = K0 x [γañ x dañ + γs x (H + dbn/2 + htt)]

=

5.78

Min horizontal pressure pA (T/m2)

PA = K0 x [γañ x dañ + γs x (H + dbn/2) ]

=

1.86

Self weigth of top slab Wbn (T/m2)

Wbn = γc x dbn

=


0.88

Self weigth of bottom slab Wbđ (T/m2)

Wbñ = γc x dbñ

=

0.88

Ww = γw x h1 x Ltt

=

4.00

3.6.1.2.5

=

0.51

y1=2.28x10-3γ (1+IM/100).P (3.6.1.2.5-1)

=

0.29

IM(%)=33x(1-4.1x10 (H+dad)) (3.6.2.2-1)
P (N) (3.6.1.2.5-1)

X= 1.8+1.2+1.8+x1+2.(H+dad)
Y=y1+2.(H+dad)
p=P/(X.Y)

=
=
=
=
=

33%
220000
8.57
3.55
0.74

m.WL/3.5

=

0.27

Z=H+dad+dbn/2+htt

=

6.155

3.11.6.2


=

0.75

Pavement load Wađ (T/m2)
Backfill load We (T/m2)

3 Water loads
Prerssure of water Ww (T/m2)
4 Live loads ( Design vehicular and Design Lane )
Distributing tire pressure on the top slab of box culvert
Width of horizontal contact x1 (m)
Length of longitudinal contact y1 (m)
In which: IM dynamic load (%)
Axle vehicular load (N)
Contact width on top slab of box culvert X (m)
Contact length on top slab ob box culvert y (m)
Total load on a calculated box culver segment (T/m2)
Design lane load WL (T/m2)
5 Additional backfill load of vehicular
Depth of bottom slab from road Z (m)
Equivalent heigth of soil for the design truck heq (m)

-4


Load of additional live load: ∆p (T/m2)
6 Defining coefficient of subgrade reaction
Scale factor of foundation K (T/m3)
Distance of two point pring support Lg (m)

Coefficent of subgrade reaction Kz (T/m2)

∆p=ko.γ.heq

=

0.68

22 TCN 18-79

=
=
=

400
0.54
218

Kz=KxLg


Project :
Item

Trung Luong - My Thuan Expressway
Box Culvert 4x4M

CALCULATION SHEET OF BOX CULVERT ACCORDING TO 22TCN272-05
II. Load combinations
No Kind of loads


Units

Service I

Strength Ia

Strength Ib

Factor

value

Factor

Value

Factor

Value

Dead load
1

Pavement load Wañ

T/m2

1.00


1.92

1.50

2.88

1.50

2.88

2

Backfill load We

T/m2

1.00

1.49

1.50

2.24

1.50

2.24

3


Max horizontal pressure PA

T/m2

1.00

5.78

1.50

8.67

0.90

5.20

4

Min horizontal pressure pA

T/m2

1.00

1.86

1.50

2.80


0.90

1.68

T/m2

1.00

4.00

1.00

4.00

1.00

4.00

T/m2

1.00

0.74

1.75

1.29

1.75


1.29

T/m2

1.00

0.27

1.75

0.47

1.75

0.47

T/m2

1.00

0.68

1.75

1.18

1.75

1.18


Water load
5

Water pressure Ww
Live load

6

Tire pressure distribution on the top slab of box culvert

7 Design lane load WL
10 Load of additional live load ∆p


KẾT QUẢ PHÂN TÍCH (RESULT OF ANALYSIS)
1. SƠ ĐỒ TÍNH TOÁN (DESIGN SHEME)

2. MOMENT DIAGRAMS
2.1 Mxx
a. Strength Ia
(Mặt cắt duyệt nội lực – Checking position of moment)


(Biểu đồ moment Mxx– Moment diagram Mxx)

b. Strength Ib
(Biểu đồ moment Mxx– Moment diagram Mxx)


c. Service


2.1 Myy
a. Strength Ia
(Mặt cắt duyệt nội lực – Checking position of moment)


(Biểu đồ moment Myy– Moment diagram Myy)

b. Strength Ib
(Biểu đồ moment Myy– Moment diagram Myy)


c. Service
(Biểu đồ moment Myy– Moment diagram Myy)

3. SHEAR DIAGRAMS
3.1 Qxx (Strength Ib)
(Mặt cắt duyệt nội lực – Checking position of shear)


(Biểu đồ lực cắt Qxx– Shear diagram Qxx)

3.2 Qyy (Strength Ia)
(Mặt cắt duyệt nội lực – Checking position of shear)


(Biểu đồ lực cắt Qyy– Shear diagram Qyy)

4. AXIAL FORCE DIAGRAMS
4.1 Fxx (strength Ib)

(Mặt cắt duyệt nội lực – Checking position of axial force)


(Biểu đồ lực dọc Fxx– Axial force diagram Fxx)

4.2 Fyy (strength Ia)
(Mặt cắt duyệt nội lực – Checking position of axial force)


(Biểu đồ lực dọc Fyy– Axial force diagram Fyy)


Project:

Trung Luong - My Thuan Expressway

Item

Box Culvert 4x4M

Section:

Bottom Slab (Checking to X axis - cross section of box culvert )

CHECKING FLEXURAL & AXIAL RESISTANCE
The factored flexural resistance Mr shall be taken as: Mr=ϕMn
Mn=Asfy(ds-a/2)-A'sf'y(d's-a/2)
Where :
- Mn : Nominal resistance
- ϕ : Resistance factor as specified in Article 5.5.4.2

- As : Area of nonprestressed tension reinforcement
- A's : Area of compression reinforcement
- fy : Specified yield strength of tension reinforcement.
- f'y : Specified yield strength of compression reinforcement
- ds : Distance from extreme compression fiber to the centiod of nonprestressed tension reinforcement
- d : Distance from extreme tension fiber to the centriod of nonprestressed tension reinforcement
- d's : Distance from extreme compression fiber to the centriod of compression reinforcement
- a : Depth of the equivalent stress block = c β 1
− β1 : Stress block factor specified in Article 5.7.2.2

0.84

- c : Distance from neutral axis to the extreme compression fiber = [Asfy-A'sf'y]/(0.85f'cβ 1b)

1- Checking load
Maximum axial force

N

Maximum moment

M

176.6 kN
93.2 kN.m

2- Checking cross section
h

350 mm


b

1,000 mm

d's

91.5 mm

d

66.5 mm

ds

284 mm

3- Materials
Specified yield strength of tension reinforcement

fy

400 MPa

Specified yield strength of compression reinforcement

f'y

400 MPa


Specified compressive strength of concrete

f'c

30 MPa

Modulus of elasticity of steel

Es

200,000 MPa

Modulus of elasticity of concrete

Ec

29,440 MPa

4 - Reinforcement
Tension reinforcement As
D
As-1bar

25.0 mm
490.87 mm2

Nos

8


As

3,927 mm2

Compression reinforcement A's
D

25.0 mm


Project:

Trung Luong - My Thuan Expressway

Item

Box Culvert 4x4M

Section:

Bottom Slab (Checking to X axis - cross section of box culvert )

A's-1bar

490.87 mm2

Nos

8


A's

3927 mm2

5 - Checking flexural resistance
c=

73.70923 mm

a=

61.60 mm

Mn

302 kN.m

- ϕ : Flexural resistance and compression factor of concrete

0.9

Mr=ϕMn

271 kN.m

Checking:

Mr =

271


>

ϕM =

93

Satisfactory

6. For cracking moment
Apllied formular :
ϕMn ≥ Min (1.2 Mcr, 1.33M)
For which :
Mcr = frIg/yt

- Modulus of rupture of concrete fr = 0.63f'c0.5

3.45 Mpa
3,572,916,667 mm4

- Moment of inertia of gross concrete section Ig :
- Distance from neutral axis to the extreme tension fiber yt:
Checking:

175 mm

ϕMn =

271


> 1.2Mcr =

85 Satisfactory

7. Checking for maximum reinforcement :
The maximum amount of nonprestressed reinforcement shall be such that :
c/de ≤ 0.42
Where:
de = (As*fy*ds)/(As*fy)
- de : the corresponding effective depth from the extreme compression fiber to the centriod of the tensile force in the tensile reinforcement (mm)
Checking:

c/de =

0.26

<

0.42

Satisfatory

8. Checking for minimum reinforcement :
The minimum amount of nonprestressed reinforcement shall be such that :
ρmin ≥ 0.03f'c/f'y
− ρmin : ratio of tension reinforcement and effective concrete area

ρmin=As/Ac

- Area of tension reinforcement


As =

3,927 mm2

- Effective area of concrete

Ac =

283,500 mm2
ρmin=As/Ac

0.0139

0.03f'c/f'y =
Checking:

ρmin =

0.01385

>

0.0023
0.03f'c/f'y =

0.00225 Satisfactory

9. Control cracking by distribution of reinforcement:
Checking load combination is Service load

M=

52.0 kN.m

Condition:
fs ≤ fsa = Z/(dcA)1/3 ≤ 0.6 f'y
+ Minimum reinforcement

ρ

0.01385


Project:

Trung Luong - My Thuan Expressway

Item

Box Culvert 4x4M

Section:

Bottom Slab (Checking to X axis - cross section of box culvert )

+ Es/Ec

n

6.79


+k

k

0.350

+j

j

0.883

fs =

52.87 Mpa

dc: depth of concrete measured from extreme tension fiber to center of bar located closest hereto, for calculation purpose, the thickness
of clear cover used to compute dc shall not be taken to be greater than 50mm.
A: Area of concrete surrounding tension reinforcement
Z: crack width parameter
+ 30 kN/mm for members in moderate exposure conditions
+ 23 kN/mm for members in severe exposure conditions
+ 17.5 kN/mm for buried structures
+ f'y : Specified yield strength of compression reinforcement

400 Mpa

dc (actually)=


75.0 mm

dc (choosen) =

50.0 mm
8,312.5 mm2

A=
Z=

17.5 kN/mm

fs =

52.9 Mpa

fsa=

234 Mpa

0.6f'y=

240 Mpa

Checking:

fs =

52.9


<

min(fsa; 06f'y)=

234

Satisfactory

and

fsa =

234

<

06f'y=

240

Satisfactory

176,580

Satisfactory

10. Checking axial compression:
Axial resistance of components shall be taken as: Pr = ϕ Pn
For members with spiral reinforcement:


Pn = 0.85 [0.85f'c(Ag-Ast) + fyAst]

For members with tie reinforcement:

Pn = 0.8 [0.85f'c(Ag-Ast) + fyAst]

Type of reinforcement:

Tie 0.75 -

ϕ: axial compression factor

350,000.0 mm2

Ag: gross area of section

7,854.0 mm2

Ast: total area of longitudinal reinforcement

9,493,052.9 N

Pn: nominal axial resistance

7,119,789.67 N

Pr: calculation axial resistance
Checking:

Pr =


7,119,790

>

min(fsa; 06f'y)=


Project:

Trung Luong - My Thuan Expressway

Item

Box Culvert 4x4M

Section:

Bottom Slab (Checking to X axis - cross section of box culvert )

CHECKING SHEAR RESISTANCE
Materials
Yield strength of reinforcement

fy

Elastic modulus of Prestressing Steel

Ep


197,000 MPa

Elastic modulus of Reinforcement

Es

200,000 MPa

Elastic modulus of Concrete

Ec

26,630 MPa

Compress strength of concrete

f'c

Maximum moment

Mu

Maximum shear

Vu

Depth

h


Effective web width

bw

1,000 mm

Distance from extreme tension fiber to the centroid tensile reinforcement

ds

66.5 mm

400 MPa

30 MPa

Checking load
93,195 N.mm
162,846 N

Section properties
350 mm

Tension reinforcement
- Diameter

mm

25


- Quantity

bar

- Area of cross section of tensile reinforcement

Ast

3,927 mm2

Distance from extreme compression fiber to the centroid tensile reinforcement

dst

284 mm

Effective shear depth

dv

252 mm

8

Sức kháng cắt Vr = ϕ Vn
Vn = min {ϕ(Vc + Vs + Vp); 0.25f'cbvdv + Vp}
+ Vc : nominal shear resistance of concrete

0.083*b*(f'c)^0.5*bw*dv


+ Vs : nominal shear resistance of reinforcement

Ay*fy*dv*(cosq+cosa)*sina)/s

* α : angle of inclination of transverse reinforcement to longitudinal axis
* b : factor indicating ability of diagonally cracked concrete to transmit tension
* q : inclination angle of diagonal compressive stress
+ Vp : component of effective prestresed force in the direction of the applied shear

Xác định b & q

Resistance factor for shear

ϕ

Factor indicating ability of diagonally cracked concrete to transmit tension

β

Strain in the tensile reinforcement

εξ

0.9
3.8
0.000

Inclination angle of diagonal compressive stress

θ


Vc

Nominal shear resistance of concrete

Vc

439,595 N

Vp

Component of effective prestresed force in the direction of the applied shear

Vp

0 N

Checking region requiring transverse reinforcement: Vu và 0.5ϕ(Vc+Vp)
Minimum tranverse reinforcement within distance s s:

27.46 độ

Unncessary
Av

170.479 mm2

Data of transverse reinforcement
Group 1
Angle of inclination of transverse reinforcement to longitudinal axis


α1

Spacing of stirrups

s1

90 degrees
150 mm

Area of shear reinforcement within a distance s: Av1
12 mm

- Diameter
- Quantity
- Area of cross section of shear reinforcement
Nominal shear resistance of reinforcement

Av1

-

mm2

Vs1

-

N


Group 2
Angle of inclination of transverse reinforcement to longitudinal axis

α2

Spacing of stirrups

s2

45 degrees
500 mm

Area of shear reinforcement within a distance s: Av2
- Diameter

12 mm


Project:

Trung Luong - My Thuan Expressway

Item

Box Culvert 4x4M

Section:

Bottom Slab (Checking to X axis - cross section of box culvert )
-


- Quantity
- Area of cross section of shear reinforcement
Nominal shear resistance of reinforcement

Av2

-

mm

Vs2

-

N

-

N

Vs1 + Vs2
Vn

Nominal shear resistance
Calculation shear resistance
Checking:

Vr =


395,636

439,595 N

Vr
>

2

395,636 N
Vu =

162,846

Satisfactory


Project:

Trung Luong - My Thuan Expressway

Item

Box Culvert 4x4M

Section:

Bottom Slab (Checking to Y axis - longitudinal section of box culvert )

CHECKING FLEXURAL & AXIAL RESISTANCE

The factored flexural resistance Mr shall be taken as: Mr=ϕMn
Mn=Asfy(ds-a/2)-A'sf'y(d's-a/2)
Where :
- Mn : Nominal resistance
- ϕ : Resistance factor as specified in Article 5.5.4.2
- As : Area of nonprestressed tension reinforcement
- A's : Area of compression reinforcement
- fy : Specified yield strength of tension reinforcement.
- f'y : Specified yield strength of compression reinforcement
- ds : Distance from extreme compression fiber to the centiod of nonprestressed tension reinforcement
- d : Distance from extreme tension fiber to the centriod of nonprestressed tension reinforcement
- d's : Distance from extreme compression fiber to the centriod of compression reinforcement
- a : Depth of the equivalent stress block = c β 1
− β1 : Stress block factor specified in Article 5.7.2.2

0.84

- c : Distance from neutral axis to the extreme compression fiber = [Asfy-A'sf'y]/(0.85f'cβ 1b)

1- Checking load
Maximum axial force

N

19.6 kN

Maximum moment

M


14.7 kN.m

2- Checking cross section
h

350 mm

b

1,000 mm

d's

85 mm

d

110 mm

ds

240 mm

3- Materials
Specified yield strength of tension reinforcement

fy

400 MPa


Specified yield strength of compression reinforcement

f'y

400 MPa

Specified compressive strength of concrete

f'c

30 MPa

Modulus of elasticity of steel

Es

200,000 MPa

Modulus of elasticity of concrete

Ec

29,440 MPa

4 - Reinforcement
Tension reinforcement As
D
As-1bar
Nos
As


12.0 mm
113.10 mm2
5
565 mm2

Compression reinforcement A's
D

12.0 mm


Project:

Trung Luong - My Thuan Expressway

Item

Box Culvert 4x4M

Section:

Bottom Slab (Checking to Y axis - longitudinal section of box culvert )

A's-1bar

113.10 mm2

Nos


5

A's

565 mm2

5 - Checking flexural resistance
c=

10.61413 mm

a=

8.87 mm

Mn

35 kN.m

- ϕ : Flexural resistance and compression factor of concrete

0.9

Mr=ϕMn

32 kN.m

Checking:

Mr =


32

>

ϕM =

15

Satisfactory

6. For cracking moment
Apllied formular :
ϕMn ≥ Min (1.2 Mcr, 1.33M)
For which :
Mcr = frIg/yt

- Modulus of rupture of concrete fr = 0.63f'c0.5

3.45 Mpa
3,572,916,667 mm4

- Moment of inertia of gross concrete section Ig :
- Distance from neutral axis to the extreme tension fiber yt:
Checking:

175 mm

ϕMn =


32

> 1.2Mcr =

20 Satisfactory

7. Checking for maximum reinforcement :
The maximum amount of nonprestressed reinforcement shall be such that :
c/de ≤ 0.42
Where:
de = (As*fy*ds)/(As*fy)
- de : the corresponding effective depth from the extreme compression fiber to the centriod of the tensile force in the tensile reinforcement (mm)
Checking:

c/de =

0.04

<

0.42

Satisfatory

8. Checking for minimum reinforcement :
The minimum amount of nonprestressed reinforcement shall be such that :
ρmin ≥ 0.03f'c/f'y
− ρmin : ratio of tension reinforcement and effective concrete area

ρmin=As/Ac


- Area of tension reinforcement

As =

565 mm2

- Effective area of concrete

Ac =

240,000 mm2
ρmin=As/Ac

0.0024

0.03f'c/f'y =
Checking:

ρmin =

0.00236

>

0.0023
0.03f'c/f'y =

0.00225 Satisfactory


9. Control cracking by distribution of reinforcement:
Checking load combination is Service load
M=

10.8 kN.m

Condition:
fs ≤ fsa = Z/(dcA)1/3 ≤ 0.6 f'y
+ Minimum reinforcement

ρ

0.00236


Project:

Trung Luong - My Thuan Expressway

Item

Box Culvert 4x4M

Section:

Bottom Slab (Checking to Y axis - longitudinal section of box culvert )

+ Es/Ec

n


6.79

+k

k

0.164

+j

j

0.945

fs =

84.10 Mpa

dc: depth of concrete measured from extreme tension fiber to center of bar located closest hereto, for calculation purpose, the thickness
of clear cover used to compute dc shall not be taken to be greater than 50mm.
A: Area of concrete surrounding tension reinforcement
Z: crack width parameter
+ 30 kN/mm for members in moderate exposure conditions
+ 23 kN/mm for members in severe exposure conditions
+ 17.5 kN/mm for buried structures
+ f'y : Specified yield strength of compression reinforcement

400 Mpa


dc (actually)=

75.0 mm

dc (choosen) =

50.0 mm
22,000.0 mm2

A=
Z=

17.5 kN/mm

fs =

84.1 Mpa

fsa=

170 Mpa

0.6f'y=

240 Mpa

Checking:

fs =


84.1

<

min(fsa; 06f'y)=

170

Satisfactory

and

fsa =

170

<

06f'y=

240

Satisfactory

19,620

Satisfactory

10. Checking axial compression:
Axial resistance of components shall be taken as: Pr = ϕ Pn

For members with spiral reinforcement:

Pn = 0.85 [0.85f'c(Ag-Ast) + fyAst]

For members with tie reinforcement:

Pn = 0.8 [0.85f'c(Ag-Ast) + fyAst]

Type of reinforcement:

Tie 0.75 -

ϕ: axial compression factor

350,000.0 mm2

Ag: gross area of section

1,131.0 mm2

Ast: total area of longitudinal reinforcement

7,478,839.6 N

Pn: nominal axial resistance

5,609,129.71 N

Pr: calculation axial resistance
Checking:


Pr =

5,609,130

>

min(fsa; 06f'y)=


Project:

Trung Luong - My Thuan Expressway

Item

Box Culvert 4x4M

Section:

Bottom Slab (Checking to Y axis - longitudinal section of box culvert )

CHECKING SHEAR RESISTANCE
Materials
Yield strength of reinforcement

fy

Elastic modulus of Prestressing Steel


Ep

197,000 MPa

Elastic modulus of Reinforcement

Es

200,000 MPa

Elastic modulus of Concrete

Ec

26,630 MPa

Compress strength of concrete

f'c

Maximum moment

Mu

14,715 N.mm

Maximum shear

Vu


27,468 N

Depth

h

Effective web width

bw

1,000 mm

Distance from extreme tension fiber to the centroid tensile reinforcement

ds

110 mm

400 MPa

30 MPa

Checking load

Section properties
350 mm

Tension reinforcement
- Diameter


mm

12

- Quantity

bar

- Area of cross section of tensile reinforcement

Ast

565 mm2

Distance from extreme compression fiber to the centroid tensile reinforcement

dst

240 mm

Effective shear depth

dv

252 mm

5

Sức kháng cắt Vr = ϕ Vn
Vn = min {ϕ(Vc + Vs + Vp); 0.25f'cbvdv + Vp}

+ Vc : nominal shear resistance of concrete

0.083*b*(f'c)^0.5*bw*dv

+ Vs : nominal shear resistance of reinforcement

Ay*fy*dv*(cosq+cosa)*sina)/s

* α : angle of inclination of transverse reinforcement to longitudinal axis
* b : factor indicating ability of diagonally cracked concrete to transmit tension
* q : inclination angle of diagonal compressive stress
+ Vp : component of effective prestresed force in the direction of the applied shear
Resistance factor for shear

ϕ

0.9

Factor indicating ability of diagonally cracked concrete to transmit tension

β

3.7

Strain in the tensile reinforcement

εξ

0.000


Inclination angle of diagonal compressive stress

θ

27.79 độ

Vc

Nominal shear resistance of concrete

Vc

Vp

Component of effective prestresed force in the direction of the applied shear

Vp

Xác định b & q

Checking region requiring transverse reinforcement: Vu và 0.5ϕ(Vc+Vp)
Minimum tranverse reinforcement within distance s s:

426,796 N
0 N
Unncessary

Av

170.479 mm2


Data of transverse reinforcement
Group 1
Angle of inclination of transverse reinforcement to longitudinal axis

α1

Spacing of stirrups

s1

90 degrees
150 mm

Area of shear reinforcement within a distance s: Av1
12 mm

- Diameter
- Quantity
- Area of cross section of shear reinforcement
Nominal shear resistance of reinforcement

Av1

-

mm2

Vs1


-

N

Group 2
Angle of inclination of transverse reinforcement to longitudinal axis

α2

Spacing of stirrups

s2

45 degrees
500 mm

Area of shear reinforcement within a distance s: Av2
- Diameter
- Quantity

12 mm
-


Project:

Trung Luong - My Thuan Expressway

Item


Box Culvert 4x4M

Section:

Bottom Slab (Checking to Y axis - longitudinal section of box culvert )
Av2

-

mm

Vs2

-

N

-

N

Nominal shear resistance

Vn

426,796 N

Calculation shear resistance

Vr


384,117 N

- Area of cross section of shear reinforcement
Nominal shear resistance of reinforcement
Vs1 + Vs2

Checking:

Vr =

384,117

>

Vu =

27,468

2

Satisfactory



×