BS ISO 10928-2009 塑料管道系统.玻璃纤维增强热固性塑料(GRP)管材和管件.回归分析方法及其使用.pdf

BS ISO 109282009 ICS 23.040.20; 23.040.45 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW BRITISH STANDARD Plastics piping systems Glass-reinforced thermosetting plastics GRP pipes and fittings s for regression analysis and their use This British Standard was published under the authority of the Standards Policy and Strategy Committee on 30 September 2009 BSI 2009 ISBN 978 0 580 56668 4 Amendments/corrigenda issued since publication DateComments BS ISO 109282009 National foreword This British Standard is the UK implementation of ISO 109282009. The UK participation in its preparation was entrusted to Technical Committee PRI/88/2, Plastics piping for pressure applications. A list of organizations represented on this committee can be obtained on request to its secretary. This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. Compliance with a British Standard cannot confer immunity from legal obligations. 标准分享网 w w w .b z f x w .c o m 免费下载 w w w . b z f x w . c o m BS ISO 109282009 Reference number ISO 109282009E ISO 2009 INTERNATIONAL STANDARD ISO 10928 Second edition 2009-09-15 Plastics piping systems Glass- reinforced thermosetting plastics GRP pipes and fittings s for regression analysis and their use Systmes de canalisation en matires plastiques Tubes et raccords plastiques thermodurcissables renforcs de verre PRV Mthodes pour une analyse de rgression et leurs utilisations w w w . b z f x w . c o m BS ISO 109282009 ISO 109282009E PDF disclaimer This PDF file may contain embedded typefaces. In accordance with Adobes licensing policy, this file may be printed or viewed but shall not be edited unless the typefaces which are embedded are licensed to and installed on the computer pering the editing. In downloading this file, parties accept therein the respons bility of not infringing Adobes licensing policy. The ISO Central Secretariat accepts no liability in this area. Adobe is a trademark of Adobe Systems Incorporated. Details of the software products used to create this PDF file can be found in the General Info relative to the file; the PDF-creation parameters were optimized for printing. Every care has been taken to ensure that the file is suitable for use by ISO member bodies. In the unlikely event that a problem relating to it is found, please in the Central Secretariat at the address given below. COPYRIGHT PROTECTED DOCUMENT ISO 2009 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or ISOs member body in the country of the requester. ISO copyright office Case postale 56 CH-1211 Geneva 20 Tel. 41 22 749 01 11 Fax 41 22 749 09 47 E-mail copyrightiso.org Web www.iso.org Published in Switzerland ii ISO 2009 – All rights reserved 标准分享网 w w w .b z f x w .c o m 免费下载 w w w . b z f x w . c o m BS ISO 109282009 ISO 109282009E ISO 2009 – All rights reserved iii Contents Page Foreword ............................................................................................................................................................iv Introduction.........................................................................................................................................................v 1 Scope......................................................................................................................................................1 2 Principle..................................................................................................................................................1 3 Procedures for determining the linear relationships – s A and B.......................................1 3.1 Procedures common to s A and B..........................................................................................1 3.2 A – Covariance ...........................................................................................................2 3.3 B – Regression with time as the independent variable.......................................................8 4 Application of s to product design and testing...................................................................11 4.1 General .................................................................................................................................................11 4.2 Product design ....................................................................................................................................12 4.3 Comparison to a specified value .......................................................................................................12 4.4 Declaration of a long-term value........................................................................................................12 Annex A normative GRP pressure pipe design procedure........................................................................13 Annex B inative Second-order polynomial relationships...................................................................20 Annex C inative Non-linear relationships.............................................................................................25 Annex D inative Calculation of lower confidence and prediction limits for A ...................49 Bibliography......................................................................................................................................................51 w w w . b z f x w . c o m BS ISO 109282009 ISO 109282009E iv ISO 2009 – All rights reserved Foreword ISO the International Organization for Standardization is a worldwide federation of national standards bodies ISO member bodies. The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission IEC on all matters of electrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 of the member bodies casting a vote. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. ISO 10928 was prepared by Technical Committee ISO/TC 138, Plastics pipes, fittings and valves for the transport of fluids, Subcommittee SC 6, Reinforced plastics pipes and fittings for all applications. This second edition cancels and replaces the first edition ISO 109281997, which has been technically revised. 标准分享网 w w w .b z f x w .c o m 免费下载 w w w . b z f x w . c o m BS ISO 109282009 ISO 109282009E ISO 2009 – All rights reserved v Introduction This International Standard describes the procedures intended for analysing the regression of test data, usually with respect to time and the use of the results in design and assessment of conity with perance requirements. Its applicability is limited to use with data obtained from tests carried out on samples. The referring standards require estimates to be made of the long-term properties of the pipe for such parameters as circumferential tensile strength, long-term ring deflection, strain-corrosion and creep or relaxation stiffness. A range of statistical techniques that could be used to analyse the test data produced by destructive tests was investigated. Many of these simple techniques require the logarithms of the data to a be normally distributed, b produce a regression line having a negative slope, and c have a sufficiently high regression correlation see Table 1. Whilst the last two conditions can be satisfied, analysis shows that there is a skew to the distribution and hence this primary condition is not satisfied. Further investigation into techniques that can handle skewed distributions resulted in the adoption of the covariance of analysis of such data for this International Standard. However, the results from non-destructive tests, such as long-term creep or relaxation stiffness, often satisfy all three conditions and hence a simpler procedure, using time as the independent variable, can also be used in accordance with this International Standard. These data analysis procedures are limited to analysis s specified in ISO product standards or test s. However, other analysis procedures can be useful for the extrapolation and prediction of long-term behaviour of some properties of glass-reinforced thermosetting plastics GRP piping products. For example, a second-order polynomial analysis is sometimes useful in the extrapolation of creep and relaxation data. This is particularly the case for analysing shorter term data, where the shape of the creep or relaxation curve can deviate considerably from linear. A second-order polynomial analysis is included in Annex B. In Annex C, there is an alternative non-linear analysis . These non-linear s are provided only for ination and the possible use in investigating the behaviour of a particular piping product or material, therefore they might not be generally applicable to other piping products. w w w . b z f x w . c o m BS ISO 109282009 标准分享网 w w w .b z f x w .c o m 免费下载 w w w . b z f x w . c o m BS ISO 109282009 INTERNATIONAL STANDARD ISO 109282009E ISO 2009 – All rights reserved 1 Plastics piping systems Glass-reinforced thermosetting plastics GRP pipes and fittings s for regression analysis and their use 1 Scope This International Standard specifies procedures suitable for the analysis of data which, when converted into logarithms of the values, have either a normal or a skewed distribution. It is intended for use with the test s and referring standards for glass-reinforced thermosetting plastics GRP pipes or fittings for the analysis of properties as a function of time. However, it can be used for the analysis of other data. Depending upon the nature of the data, two s are specified. The extrapolation using these techniques typically extends the trend from data gathered over a period of approximately 10 000 h, to a prediction of the property at 50 years, which is the typical maximum extrapolation time. This International Standard only addresses the analysis of data. The test procedures to collect the data, the number of samples required and the time period over which data is collected, are covered by the referring standards and/or test s. Clause 4 discusses how the data analysis s are applied to product testing and design. 2 Principle Data are analysed for regression using s based on least squares analysis which can accommodate the incidence of a skew and/or a normal distribution. The two s of analysis used are the following ⎯ A covariance using a first-order relationship; ⎯ B least squares, with time as the independent variable using a first-order relationship. The s include statistical tests for the correlation of the data and the suitability for extrapolation. 3 Procedures for determining the linear relationships – s A and B 3.1 Procedures common to s A and B Use A see 3.2 or B see 3.3 to fit a straight line of the given in Equation 1 yabx 1 where y is the logarithm, lg, of the property being investigated; a is the intercept on the Y-axis; b is the slope; x is the logarithm, lg, of the time, in hours. w w w . b z f x w . c o m BS ISO 109282009 ISO 109282009E 2 ISO 2009 – All rights reserved 3.2 A – Covariance 3.2.1 General For A, calculate the following variables in accordance with 3.2.2 to 3.2.5, using Equations 2, 3 and 4 2 y i yY Q n − ∑ 2 2 x i xX Q n − ∑ 3 xy ii xXyY Q n ⎡⎤−− ⎣⎦ ∑ 4 where Qy is the sum of the squared residuals parallel to the Y-axis, divided by n; Qx is the sum of the squared residuals parallel to the X-axis, divided by n; Qxy is the sum of the squared residuals perpendicular to the line, divided by n; Y is the arithmetic mean of the y data, i.e. given as Equation 5 i y Y n ∑ 5 X is the arithmetic mean of the x data, i.e. given as Equation 6 i x X n ∑ 6 xi, yi are individual values; n is the total number of results pairs of readings for xi, yi. NOTE If the value of Qxy is greater than zero, the slope of the line is positive and if the value of Qxy is less than zero, then the slope is negative. 3.2.2 Suitability of data Calculate the linear coefficient of correlation, r, using Equations 7 and 8 2 xy 2 xy Q r QQ 7 0,5 2 rr 8 标准分享网 w w w .b z f x w .c o m 免费下载 w w w . b z f x w . c o m BS ISO 109282009 ISO 109282009E ISO 2009 – All rights reserved 3 If the value of r is less than 2 Students 2Students t f nt f⎡⎤− ⎣⎦ then the data are unsuitable for analysis. Table 1 gives the minimum acceptable values of the correlation coefficient, r, as a function of the number of variables, n. The Students t value is based on a two-sided 0,01 level of significance. Table 1 Minimum values of the correlation coefficient, r, for acceptable data from n pairs of data Number of variables n Degrees of freedom n − 2 Students t0,01 Minimum r 13 11 3,106 0,683 5 14 12 3,055 0,661 4 15 13 3,012 0,641 1 16 14 2,977 0,622 6 17 15 2,947 0,605 5 18 16 2,921 0,589 7 19 17 2,898 0,575 1 20 18 2,878 0,561 4 21 19 2,861 0,548 7 22 20 2,845 0,536 8 23 21 2,831 0,525 6 24 22 2,819 0,515 1 25 23 2,807 0,505 2 Number of variables n Degrees of freedom n − 2 Students t0,01 Minimum r 26 24 2,797 0,495 8 27 25 2,787 0,486 9 32 30 2,750 0,448 7 37 35 2,724 0,418 2 42 40 2,704 0,393 2 47 45 2,690 0,372 1 52 50 2,678 0,354 2 62 60 2,660 0,324 8 72 70 2,648 0,301 7 82 80 2,639 0,283 0 92 90 2,632 0,267 3 102 100 2,626 0,254 0 3.2.3 Functional relationships To find a and b for the functional relationship line yabx 1 First set Γ as given in Equation 9