din-1055-6-2005_parte1

DIN 1055-6:2005-03

CONTENTS Page

Foreword 7

1 scope 8

2 references to other standards 10

3 terms and symbols 11

3.1 terms 11

3.2 symbols 15

3.2.1 General 15

3.2.3 Latin letters, capital 15

3.2.3 Latin letters, small 17

3.2.4 Greek letters, capital 20

3.2.5 Greek letters, small 20

4 illustration and classification of actions 21

4.1 illustration of action in silos 21

5.6 principles of calculations for explosions 30

6 bulk material parameters 31

6.1 general 31

6.2 bulk material parameters 32

6.2.1 General 32

6.2.2 Determination of bulk material parameters 34

6.2.3 Simplified procedure 35

6.3 measurement of bulk material parameters in tests 35

6.3.1 Experimental determination 35

6.3.2 Bulk material density, 36 6.3.3 Coefficients of wall friction 36 6.3.4 Angle of inner friction, i 36 6.3.5 Horizontal load ration,K 37

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DIN 1055-6:2005-03

6.3.6 Cohesiveness, 37 C

6.3.7 Bulk material correction value for the reference-surface load 37 opC

7 loads on vertical silo walls 38

7.1 general 38

7.2 slim silos 39

7.2.1 Fill loads on vertical silo walls 39

7.2.2 Discharge loads on vertical walls 44

7.2.3 Uniform increase of loads in place of reference-surface loads for fills and

discharges of the load-types for circular silos 49

7.2.4 Discharge loads for circular silos with large eccentricities during discharge 50

7.3 low silos and silos of medium slimness 55

7.3.1 Fill loads on the vertical walls

7.3.2 Discharge loads on the vertical walls 57

7.3.3 Large eccentricities for filling in of circular low silos and circular silos

of medium slimness 59

7.3.4 large discharge eccentricities for filling in of circular low silos and

Circular silos of medium slimness 60

7.4 silos with braced walls 61

7.4.1 Fill loads on vertical walls 61

7.4.2 Discharge loads on vertical walls 62

7.5 silos with fluidized bulk material 62

7.5.1 General 62

7.5.2 Loads in silos for storage of fluidized bulk material 62

7.6 temperature differences between bulk material and silo structure 63

7.6.1 general 63

7.6.2 loads due to a decrease in the surrounding atmospheric temperature 64

7.6.3 loads due to filling-in of hot bulk materials 64

7.7 loads in rectangular silos 65

7.7.1 Rectangular silos 65

7.7.2 Silos with internal braces 65

8 loads in silo hoppers and silo bottoms 65

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8.1 general 65

8.1.1 Physical parameters 65

8.1.2 General rules 67

8.2 horizontal silo bottoms 69

8.2.1 Vertical loads on horizontal silo bottoms in slim silos 69

8.2.2 Vertical loads on level silo bottoms in low silos and silos of

Medium slimness 69

8.3 steep hoppers 71

8.3.1 Mobilized friction 71

8.3.2 Fill loads 71

8.3.3 Discharge loads 71

8.4 flat hoppers 72

8.4.1 Mobilized friction 72

8.4.2 Fill loads 73

8.4.3 Discharge loads 73

8.5 hopper loads in silos with air-injection equipment 73

9 loads on tanks 74

9.1 general 74

9.2 loads due to stored fluids 74

9.3 parameters for fluids 74

9.4 suction loads due to insufficient aeration 74

Annex A (informative) Basis for the Planning of Structures

Rules that complement DIN 1055-100 for silos and tanks 75

A.1 general 75

A.2 border limit for load capacity 75

A.2.1 part-safety correction value 75

A.2.2 Actions on structures - Actions in silos and tanks correction value

75

A.4 conditions for calculation and action-combinations for the

Requirement categories 2 and 3 76

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A.5 action-combinations for the

Requirement category 1 77

Annex B (normative) Actions, Part-Safety Factors and Composite

Correction Values for the actions on tanks 78

B.1 general 78

B.2 actions 78

B.2.1 loads from stored fluids 78

B.2.2 loads from internal pressures 78

B.2.3 loads from temperature changes 78

B.2.4 intrinsic loads 78

B.2.5 loads from insulation 78

B.2.6 distributed working loads 79

B.2.7 concentric working loads 79

B.2.8 snow 79

B.2.9 wind 79

B.2.10 low pressure due to insufficient aeration 81

B.2.11 seismic loads 81

B.2.12 loads due to connecting structures 81

B.2.13 loads due to non-uniform settlement 81

B.2.14 catastrophic loads 81

B.3 part-safety correction values for actions 81

B.4 combination of actions 81

Annex C (normative) measurement of bulk material parameters for

Determination of silo loads 82

C.1 general 82

C.2 application 82

C.3 symbols 82

C.4 terms 83

C.5 taking of specimens and their preparation 83

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C.6 determination of bulk material density 84 C.6.1 short description 84

C.6.2 test apparatus 84

C.6.3 process / procedure 85

C.7 wall friction 85

C.7.1 general 85

C.7.2 co-efficient of wall friction m for the determination of loads 86 C.7.3 angle of wall friction wh for examining the flow behaviour 87 C.8 horizontal load ratio K 88

C.8.1 direct measurement 88

C.8.2 indirect measurement 89

C.9 stability parameters: cohesiveness c and angle of internal friction i 89 C.9.1 direct measurement 89


C.10 effective elasticity module Es 93

C.10.1 direct measurement 93


C.11 determination of the upper and lower characteristic values for the bulk

Material parameters and the determination of the conversion factor a 96

C.11.1 testing principle 96

C.11.2 assessment methods 97

Annex D (normative) assessment of bulk material parameters for determination

Of silo loads 99

D.1 goal 99

D.2 assessment of the wall friction co-efficient for a corrugated wall 99

D.3 internal friction and wall friction of a coarse-grained bulk material

Without fine particles 100

Annex E (normative) details of bulk material parameters 101

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Annex F (normative) determination of the flow profile, mass flow

And core flow 102

Annex G (normative) seismic actions 103

G.1 general 103

G.2 symbols 103

G.3 conditions for calculation 103

G.4 seismic actions 104

G.4.1 silo bottom and foundations 104

G.4.2 silo walls 104

Annex H (normative) alternative rules for determination of hopper loads 106

H.1 general 106

H.2 terms 106

H.3 symbols 106

H.4 conditions for calculation 106

H.5 loads on hopper walls 107

H.6 determination of connecting forces at the hopper junction 108

H.7 alternative equations for the hopper load correction values Fe for

The load discharge 108

Annex I (normative) action due to dust explosions 109

I.1 general 109

I.2 application 109

I.3 additional standards, guidelines and rules 109

I.4 dusts of explosive nature and their parameters 109

I.5 ignition sources 110

I.6 protective measures 110

I.7 calculation of components 111

I.8 calculation of explosive overpressure 111

I.9 calculation of negative pressure 111

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I.10 securing the closing element of the discharge opening 111

I.11 recoil forces due to pressure release 111

Diagrams

Diagram 1 illustration of silo bins with nomenclature of geometric

Parameters and loads 9

Diagram 2 basic flow profile 26

Diagram 3 flow profile with pipe flow 27

Diagram 4 flow profile with mixed bulk material flows 28

Diagram 5 effects of slimness (height to diameter ratio) on the mixed bulk

material flows and the pipe flows 28

Diagram 6 customized arrangements for fill and discharge 29

Diagram 7 conditions under which pressures due to mass flow arise 32

Diagram 8 symmetric discharge loads around the vertical silo walls 40

Diagram 9 longitudinal and cross-sectional illustrations of the load diagrams of

reference-surface loads 42

Diagram 11 longitudinal and cross-sectional illustrations of the load

diagrams of reference-surface loads during discharge 47

Diagram 12 flow channels and pressure distribution during discharge

with large eccentricities 52

Diagram 13 loads in low silos or silos with medium slimness after the

fill (fill loads) 56

Diagram 14 fill pressures during eccentric filled low silos or silos with 59

medium slimness

Diagram 15 fill pressures in a braced-wall silo 62

Diagram 16 boundaries between steep and flat hoppers 66

Diagram 17 distribution of the fill pressures in a steep and flat hopper 67

Diagram 18 bottom loads in low silos and in silos with medium slimness 70

Diagram 19 discharge pressures in a hopper with a steep and a flat inclination 72

Diagram B.1 coefficients of pressure for wind loads in circular cylindrical tanks 80

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DIN 1055-6:2005-03

Diagram C.1 equipment for determination of 85 Diagram C.2 test procedure for determination of the coefficients of wall friction 87

Diagram C.3 test procedure for determination of Ko 88

Diagram C.4 test procedure for determination of the angle of the internal

Friction i and c and the cohesiveness based upon the tension Created by pre-compression 90

Diagram C.5 test procedure for determination of the elasticity module during

loading and unloading 94

Diagram D.1 measurement of the profiling of the wall surface 100

Diagram F.1 demarcation of mass and core flow conditions in conical and

cuneiform hoppers 102

Diagram G.1 possible rearrangements oat the bulk material surface due to

Seismic actions 103

Diagram G.2 seismic actions on the substructure (e.g. braces) 104

Diagram G.3 cross-section through the vertical silo shaft with details of

the additional horizontal loads due to seismic actions 105

Diagram H.1 alternative rules for the hoppers 108 Tables

Table 1 classification of conditions for calculation 23

Table 2 relevant parameters for different load estimates 25

Table 3 categories of wall surfaces 34

Table A.1 composite correction values 77

Table C.1 test parameters 91

Table C.2 typical values for the coefficients of variation for the bulk

Material parameters 98

Table E.1 bulk material parameters 101

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DIN 1055-6:2005-03

Foreword

This standard was compiled in the NABau-AA 00.20.00 Actions on Buildings

(Spiegelausschuss zu CEN/TC/ 250/SC 1).

This standard is part of the new series DIN 1055 Actions on Structures, which consists of

the following parts:

Part 1:

Part 2:

Part 3:

Part 4:

Part 5;

Part 6;

Part 7:

Part 8:

Part 9:

Part 10:

Part 100:

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DIN 1055-6:2005-03

References to standards belonging to the series DIN 1055, contained in this standard,

refer exclusively to the above-mentioned new series DIN 1055.

This standard was developed by the Work Committee NABau 00.20.00 on the basis of

DIN V ENV 1991-4 and conforms largely to the draft manuscript prEN 1991-4.

Any deviations of this standard from the above-mentioned manuscript prEN 1991-4

conform by and large with possible commitments to the national safety standards so that,

in the case of an eventual ratification of EN 1991-4, this standard can be compatible in

the national context.

Revisions Vis--vis DIN 1055-6:1987-05 the following revisions have been made:

a) structural adaptation in line with the EN 1991-4

b) terminology adaptation in line with the EN 1991-4

c) adaptation of the calculation and safety concepts in line with the EN 1991-4

d) incorporation of regulations for actions due to dust-explosions

e) incorporation of regulations for actions due to earthquakes

f) incorporation of regulations for actions due to bulk material properties

Earlier Editions DIN 1055-6: 1964-11, 1987-05

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DIN 1055-6:2005-03

1. Scope

1) This standard contains general principles and information relating to the influences

for the design and calculations of silos for storage of bulk materials and for tanks.

It is to be applied in association with the other parts of the series DIN 1055.

2) This standard also contains stipulations for actions on silos and tanks which

extend beyond the direct action caused by the stored bulk material or fluids (e.g.

effects of temperature differences).

3) While applying the rules for calculations made for silo bins and silo structures the

following geometric limitations should be kept in mind:

--- The cross-sections of the silo bins are limited to the instances shown in diagram 1d.

Smaller deviations are allowed under the condition that the possible effects on the silo

structures due to the pressure changes resulting from these deviations will be taken into

account.

--- The foll. Limits will apply for the geometric measurements:

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din-1055-6-2005_parte1

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