Risultati di prima indagine delle prove di scivolamento alla base

Le schede sono redatte in inglese in quanto facenti parte della proposta di normazione per il miglioramento della EN 131-2.

Simboli:

P = measured pulling force (N) W = ladder weight (N)

D = dead weight (N)

 = angle of leaning ladder inclination respect to the horizontal surface d = distance of dead weight from the top of ladder

Coefficient of friction )

D +

W L

d DL 2 + +W (Ptg tg

= 1 α

μ α Stiles cap = tampone

D

L d

P W

α

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96

Figura A1 - 1 Tamponi utilizzati nelle prove di slittamento

Test: A n. 1

Model: A1 Length of ladder (m): 4 Test surface: HPL

With wheels on the top:

Yes

Angle of inclination α:

65°

Stiles cap

At top At bottom

Distance of the uppermost third rung d (m): 0.910

No cap A1

Specime n n.

Weight of ladder

W (daN)

Dead weight

D (daN)

Test

n.

Sliding time at s

t

Sliding

s (mm)

Sliding pulling force at sliding s

P (daN)

Friction of coefficient

μ

1 9.28 50

1 13’: 53’’ 50 10.25

2 12’: 44’’ 50 9.84

3 11’: 40’’ 50 7.95

4 11’: 18’’ 50 7.31

5 09’: 51’’ 50 6.01

The sliding starts at beginning of each test and proceeds continuously.

The test has been stopped at 50 mm of sliding.

The test starts with a pulling force of 0.86 daN (weight of empty bottle).

Test: A n. 2

Model: A1 Length of ladder (m): 4 Test surface: HPL

With wheels on the top:

NO

Angle of inclination α:

65°

Sliding pulling force at sliding s

The sliding starts at beginning of each test and proceeds continuously.

The test starts with a pulling force of 0.86 daN (weight of empty bottle).

a) the test has been stopped at 50 mm of sliding b) the ladder slides suddenly at time 2’: 15’’

c) the ladder slides suddenly at the beginning of the test

Test: A n. 3

Model: A2 Length of ladder (m): Test surface: HPL

With wheels on the top:

NO

Angle of inclination α:

65°

Sliding pulling force at sliding s

The sliding starts at beginning of each test and proceeds continuously.

The test has been stopped at 50 mm of sliding.

The test starts with a pulling force of 0.86 daN (weight of empty bottle).

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98 Test: A n. 4

Model: A3 Length of ladder (m): 4 Test surface: HPL

With wheels on the top:

NO

Angle of inclination α:

65°

Stiles cap

At top At bottom

Distance of the uppermost third rung d (m): 0.910

A1 A3

Specime n n.

Weight of ladder

W (daN)

Dead weight

D (daN)

Test

n.

Sliding time at s

t

Sliding

s (mm)

Sliding pulling force at sliding s

P (daN)

Note

1 9.28 50

1 17’: 15’’ 50 10.43 a)

2 23’: 20’’ 50 12.75 b)

3 24’: 30’’ 50 14.13 c)

4 24’: 45’’ 50 14.52 d)

5 27’: 56’’ 50 15.50 e)

The test starts with a pulling force of 0.86 daN (weight of empty bottle).

The sliding starts at beginning of each test and proceeds to move slowly for 5’; than it slides continuously.

The test has been stopped at 50 mm of sliding.

a) the ladder slides of 1 mm in 4’: 49’’

b) the ladder slides of 1 mm in 5’: 10’’

c) the ladder slides of 1 mm in 5’: 06’’

d) the ladder slides of 1 mm in 5’: 22’’

e) the ladder slides of 1 mm in 5’: 30’’

Test: A n. 5

Model: A4 Length of ladder (m): 4 Test surface: HPL

With wheels on the top:

NO

Angle of inclination α:

65°

Sliding pulling force at sliding s

a) the ladder slides immediately at beginning of the each test Test: A n. 6

Model: A3 Length of ladder (m): Test surface: HPL

With wheels on the top:

Yes

Angle of inclination α:

65°

Sliding pulling force at sliding s

The test has been stopped at 50 mm

a) the ladder slides slowly until 20 mm in 12’: 51’’; then the rate increases quickly b) the ladder slides slowly until 20 mm in 16’: 02’’; then the rate increases quickly c) the ladder slides slowly until 20 mm in 16’: 30’’; then the rate increases quickly d) the ladder slides slowly until 20 mm in 16’: 58’’; then the rate increases quickly e) the ladder slides slowly until 20 mm in 19’: 18’’; then the rate increases quickly

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100 Test: A n. 7

Model: A3 Length of ladder (m): 4 Test surface: HPL

With wheels on the top:

Yes

Angle of inclination α:

70° pulling force

ΔP

The test starts with a pulling force of 0.86 daN (weight of empty bottle).

Test: A n. 8

Model: A4 Length of ladder (m): 4 Test surface: HPL

With wheels on the top:

yes

Angle of inclination α:

70°

Siding pulling force at sliding s

a) At the beginning the ladder slides of 40 mm in 10’’; the test has been stopped at 50 mm of sliding.

b) The ladder slides under (W + D) only without pulling force

Test: A n. 9

Model: A3 Length of ladder (m): 4 Test surface: SS

With wheels on the top:

Yes

Angle of inclination α:

70° pulling force

ΔP

The test starts with a pulling force of 0.86 daN (weight of empty bottle).

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102 Test: A n. 10

Model: A3 Length of ladder (m): 4 Test surface: SS

With wheels on the top:

YES

Angle of inclination α:

70° pulling force

ΔP

The test starts with a pulling force of 0.86 daN (weight of empty bottle).

Test: A n. 11

Model: A5 (two pieces) Length of ladder (m): 4 Test surface: HPL

With wheels on the top:

YES

Angle of inclination α:

65°

Sliding pulling force at sliding s

Test: A n. 12

Model: A5 (two pieces) Length of ladder (m): 4 Test surface: HPL

With wheels on the top:

YES

Angle of inclination α:

65°

Sliding pulling force at sliding s

Model: A5 (two pieces) Length of ladder (m): 4 Test surface: HPL

With wheels on the top:

YES

Angle of inclination α:

70°

Sliding pulling force at sliding s

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104 Test: A n. 14/1

Model: A5 (two pieces) Length of ladder (m): 4 Test surface: HPL

With wheels on the top:

YES

Angle of inclination α:

65°

Sliding pulling force at sliding s

Model: A5 (two pieces) Length of ladder (m): 4 Test surface: HPL

With wheels on the top:

YES

Angle of inclination α:

65°

Sliding pulling force at sliding s

Test: A n. 14/3

Model: A5 (two pieces) Length of ladder (m): 4 Test surface: HPL

With wheels on the top:

YES

Angle of inclination α:

65°

Stiles cap

At top At

bottom Distance of uppermost third rung d

(m): 0.981

NO CAP A5

Specimen

n.

Weight of specimen

W (daN)

Dead weight

D (daN)

Test

n.

Sliding time at s

t (min)

Sliding

s (mm)

Sliding pulling force at sliding s

P (daN)

Note

1 10.59

Increasing dead weight continuously

until 39.53

3

5 0

10 0

16 0

20 0

25 0

30 0

35 2

40 2

45 2

50 2

55 2

60 2

65 2

72 sliding quickly

Total = 14 mm

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106 Test: A n. 14/4

Model: A5 (two pieces) Length of ladder (m): 4 Test surface: HPL

With wheels on the top:

YES

Angle of inclination α:

65°

Sliding pulling force at sliding s

Test: A n. 14/5

Model: A5 (two pieces) Length of ladder (m): 4 Test surface: HPL

With wheels on the top:

YES

Angle of inclination α:

65°

Sliding pulling force at sliding s

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108 Test: A n. 14 - Summary 4 tests

Model: A5 (two pieces) Length of ladder (m): 4 Test surface: HPL

With wheels on the top:

YES

Angle of inclination α:

65°

No pulling force applied

Test: B n. 15

Model: B1 (two pieces) Length of ladder (m): 4 Test surface: HPL

With wheels on the top:

YES

Angle of inclination α:

65°

Sliding pulling force at sliding s

The test starts with a pulling force of 0.86 daN (weight of empty bottle).

Test: B n. 16/1

Model: B1 (two pieces) Length of ladder (m): 4 Test surface: HPL

With wheels on the top:

YES

Angle of inclination α:

65°

Sliding pulling force at sliding s

The test starts with a pulling force of 0.86 daN (weight of empty bottle).

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110 Test: B n. 16/2

Model: B1 (two pieces) Length of ladder (m): 4 Test surface: HPL

With wheels on the top:

YES

Angle of inclination α:

65°

Sliding pulling force at sliding s

The test starts with a pulling force of 0.86 daN (weight of empty bottle).

Test: B n. 16/3

Model: B1 (two pieces) Length of ladder (m): 4 Test surface: HPL

With wheels on the top:

YES

Angle of inclination α:

65°

Sliding pulling force at sliding s

The test starts with a pulling force of 0.86 daN (weight of empty bottle).

Test: B n. 16/4

Model: B1 (two pieces) Length of ladder (m): 4 Test surface: HPL

With wheels on the top:

YES

Angle of inclination α:

65°

Sliding pulling force at sliding s

The test starts with a pulling force of 0.86 daN (weight of empty bottle).

Test: B n. 16/5

Model: B1 (two pieces) Length of ladder (m): 4 Test surface: HPL

With wheels on the top:

YES

Angle of inclination α:

65°

Sliding pulling force at sliding s

The test starts with a pulling force of 0.86 daN (weight of empty bottle).

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112 Test: B n. 16 - Summary 5 tests

Model: B1 (two pieces) Length of ladder (m): 4 Test surface: HPL

With wheels on the top:

YES

Angle of inclination α:

65°

Model: C1(two pieces) Length of ladder (m): 4 Test surface: HPL

With wheels on the top:

YES

Angle of inclination α:

65°

Sliding time at s force at sliding s

P

The sliding starts at beginning of each test.

The test has been stopped at 50 mm of sliding.

Test: C n. 17/2

Model: C1 (two pieces) Length of ladder (m): 4 Test surface: HPL

With wheels on the top:

YES

Angle of inclination α:

65° force at sliding

s

The sliding starts at beginning of each test.

The test has been stopped at 50 mm of sliding.

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114 Test: C n. 17/3

Model: C1 (two pieces) Length of ladder (m): 4 Test surface: HPL

With wheels on the top:

YES

Angle of inclination α:

65° force at sliding

s

 = angle of leaning ladder inclination respect to the horizontal surface d = Distance of dead weight from the top of ladder

The sliding starts at beginning of each test.

The test has been stopped at 50 mm of sliding.

Test: C n. 17/4

Model: C1 (two pieces) Length of ladder (m): 4 Test surface: HPL

With wheels on the top:

YES

Angle of inclination α:

65° force at sliding

s

 = angle of leaning ladder inclination respect to the horizontal surface d = Distance of dead weight from the top of ladder

The sliding starts at beginning of each test. The test has been stopped at 50 mm of sliding.

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116 Test: C n. 17/5

Model: C1 (two pieces) Length of ladder (m): 4 Test surface: HPL

With wheels on the top:

YES

Angle of inclination α:

65°

Sliding pulling force at sliding s

 = angle of leaning ladder inclination respect to the horizontal surface d = Distance of dead weight from the top of ladder

The sliding starts at beginning of each test.The test has been stopped at 50 mm of sliding

Test: C n. 17 - Summary of 5 tests

Model: C1 (two pieces) Length of ladder (m): 4 Test surface: HPL

With wheels on the top:

YES

Angle of inclination α:

65°

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 = angle of leaning ladder inclination respect to the horizontal surface d = Distance of dead weight from the top of ladder

The sliding starts at beginning of each test.

The test has been stopped at 50 mm of sliding.

No pulling force applied

Test: C n. 18/1

Model: C1 (two pieces) Length of ladder (m): 4 Test surface: HPL

With wheels on the top:

YES

Angle of inclination α:

65° force at sliding s

P

The sliding starts at beginning of each test.

The test has been stopped at 50 mm of sliding.

The test starts with a pulling force of 0.86 daN (weight of empty bottle).

Test: B n. 18/2

Model: C1 (two pieces) Length of ladder (m): 4 Test surface: HPL

With wheels on the top:

YES

Angle of inclination α:

65° force at sliding s

P

The sliding starts at beginning of each test.

The test has been stopped at 50 mm of sliding.

The test starts with a pulling force of 0.86 daN (weight of empty bottle).

Test: C n. 18/3

Model: C1(two pieces) Length of ladder (m): 4 Test surface: HPL

With wheels on the top:

YES

Angle of inclination α:

65° force at sliding s

P

The sliding starts at beginning of each test.

The test has been stopped at 50 mm of sliding.

The test starts with a pulling force of 0.86 daN (weight of empty bottle).

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120 Test: C n. 18/4

Model: C1(two pieces) Length of ladder (m): 4 Test surface: HPL

With wheels on the top:

YES

Angle of inclination α:

65°

Sliding pulling force at sliding s

The sliding starts at beginning of each test.

The test has been stopped at 50 mm of sliding.

The test starts with a pulling force of 0.86 daN (weight of empty bottle).

Test: C n. 18/5

Model: C1 (two pieces) Length of ladder (m): 4 Test surface: HPL

With wheels on the top:

YES

Angle of inclination α:

65° force at sliding s

P

The sliding starts at beginning of each test.

The test has been stopped at 50 mm of sliding.

The test starts with a pulling force of 0.86 daN (weight of empty bottle).

Test: C n. 18 - Summary of 5 tests

Model: C1(two pieces) Length of ladder (m): 4 Test surface: HPL

With wheels on the top:

YES

Angle of inclination α:

65°

 = angle of leaning ladder inclination respect to the horizontal surface d = Distance of dead weight from the top of ladder

The sliding starts at beginning of each test.

The test has been stopped at 50 mm of sliding.

No pulling force applied

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