ISO 9123:2017 ハイドロメトリ — ステージ-落下-放電の関係 | ページ 2

Foreword

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This document was prepared by Technical Committee ISO/TC 113, Hydrometry, Subcommittee SC 1, Velocity area methods.

This second edition cancels and replaces the first edition (ISO 9123:2001), which has been technically revised. The main changes were to improve the text relating to the stage-fall-discharge method and to revise the previous clause on uncertainty in accordance with HUG/GUM and similar related standards on the estimation of uncertainty in flow measurements.

1 Scope

This document specifies methods for determining stage-fall-discharge relationships for a stream reach where variable backwater occurs either intermittently or continuously. Two gauging stations, a base reference gauge and an auxiliary gauge are required for gauge height measurements. A number of discharge measurements are required in order to calibrate the rating to the accuracy required by this document.

The preparation of rating curves is not described in detail in this document.

2 Normative references

The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

3 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 772 apply.

Note, however that the application of the definition of backwater given in ISO 772 to the determination of discharge under intermittent or continuous backwater conditions should take into account that a higher gauge height would prevail for a given discharge than would be the case if the variable backwater was not present.

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

Bibliography