ISO/TS 20656-1:2017

TECHNICAL ISO/TS
SPECIFICATION 20656-1
First edition
2017-06
Plastics piping systems — General
rules for structural design of glass-
reinforced thermosetting plastics
(GRP) pipes —
Part 1:
Buried pipes
Systèmes de canalisation en matières plastiques - Règles générales
pour la conception structurelle des
tubes et raccords plastiques thermodurcissables renforcés de verre
(PRV) —
Partie 1: Tubes enterré
Reference number
ISO/TS 20656-1:2017(E)
©
ISO 2017

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ISO/TS 20656-1:2017(E)

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ISO/TS 20656-1:2017(E)

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Partial factor method . 2
4.1 General . 2
4.2 Reliability index, β .2
4.3 Sensitivity index, α .4
4.4 Quality management . 4
5 Partial factors for effects of actions . 5
5.1 General . 5
5.2 Partial factors for internal pressure . 5
5.2.1 General. 5
5.2.2 Model uncertainty . 6
5.2.3 Uncertainty of pressure . 7
5.2.4 Uncertainty of long-term pressure. 7
5.2.5 Uncertainty of short-term pressure . 8
5.2.6 Uncertainty of thickness and E-modulus .
...