③内力计算

④ 强度验算
檩条截面受力如图

3 所示

      
檩条全截面有效
檩条最大应力位于

B 点，对该点进

行验算

   满足要求

⑤整体稳定性验算

，，，

2

/

604

.

1

7

.

0

4

.

1

42

.

0

1

.

0

2

.

1

m

kN

q

=

×

+

+

×

=

）

（

2

/

596

.

0

8

.

21

sin

604

.

1

8

.

21

sin

m

kN

q

q

x

=

°

×

=

•

=

°

2

/

489

.

1

8

.

21

cos

604

.

1

8

.

21

cos

m

kN

q

q

y

=

°

×

=

•

=

°

m

kN

l

q

M

y

x

•

=

×

×

=

=

7

.

6

6

489

.

1

8

1

8

1

2

2

m

kN

l

q

M

x

y

•

=

×

×

=

=

67

.

0

6

596

.

0

32

1

32

1

2

2

0

.

3

93

.

2

75

220

<

=

=

b

h

31

205

205

31

30

5

.

2

75

=

<

=

=

t

b

8

8

5

.

2

20

t

a

≥

=

=

2

2

3

6

3

6

/

205

/

7

.

157

10

65

.

12

10

67

.

0

10

98

.

63

10

7

.

6

mm

N

f

mm

N

W

M

W

M

eny

y

enx

x

B

=

<

=

×

×

+

×

×

=

+

=

σ

5

.

0

=

b

µ

35

.

1

1

=

ξ

14

.

0

2

=

ξ

l

l

b

µ

=

0

14

.

0

22

/

)

11

(

14

.

0

2

/

2

2

−

=

−

×

×

=

=

h

e

a

ξ

η

8501

.

0

)

22

600

5

.

0

(

66

.

68

2028

.

0

156

.

0

66

.

68

22

05

.

6351

4

)

(

156

.

0

4

2

2

2

0

2

=

×

×

×

+

×

×

=

+

=

h

l

I

I

I

h

I

y

t

y

w

ξ

8

.

112

66

.

2

/

300

=

=

y

λ

7

.

0

215

.

1

]

14

.

0

8501

.

0

)

14

.

0

(

[

35

.

1

98

.

63

8

.

112

22

73

.

9

4320

)

(

4320

2

2

2

1

2

>

=

−

+

−

×

×

×

×

×

=

+

+

=

η

ξ

η

ξ

λ

ϕ

x

y

bx

W

Ah

865

.

0

215

.

1

274

.

0

091

.

1

274

.

0

091

.

1

'

=

−

=

−

=

bx

bx

ϕ

ϕ

2

2

3

6

3

6

'

/

205

/

174

10

65

.

12

10

67

.

0

10

98

.

63

865

.

0

10

7

.

6

mm

N

f

mm

N

W

M

W

M

eny

y

enx

bx

x

=

<

=

×

×

+

×

×

×

=

+

ϕ

图 3  檩条截面受力图