GB/T 13942.2-2009Durability of wood - Part 2: Method for field test of natural durability (English PDF)

Foreword

GB/T 13942 "Wood Durability" is divided into two parts.

--- Part 1. Laboratory test methods for natural decay;

--- Part 2. Test methods for natural durability field. This section GB/T 13942 Part 2. This Part replaces GB/T 13942.2-1992 "natural durability of wood Field test methods of the natural durability of wood." This section compared with the GB/T 13942.2-1992 The main changes are as follows:

--- Adds a smaller sample size for the underground tests;

--- Grading standards decay and termite ants reference American wood preservative association AWPAE7-07 "Methodofevaluatingwood preservativesbyfieldtestswithstakes ". This part by the State Forestry Administration. This part of the National Standardization Technical Committee centralized timber. This section is responsible for drafting units. China Forestry Science Institute of Wood Industry. Participated in the drafting of this section. Tropical Forestry, Chinese Academy of Forestry. The main drafters of this section. Jiang Mingliang, Shi Zhenhua. This part of the standard replaces the previous editions are.

--- GB/T 13942.2-1992. Wood durability Part 2. Test methods for natural durability Field

1 Scope

GB/T 13942.2-2009 is the Chinese national standard on durability of wood - part 2: method for field test of natural durability, in the field of wood technology. The /T suffix marks it as a recommended standard: it is not compulsory by itself, but it becomes binding as soon as a contract, a tender or a customer specification calls it up - which in practice is how most foreign buyers meet it. It was issued on 23 February 2009 by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China; Standardization Administration of China, and has been in force since 1 August 2009. Classification: ICS 79.020, CCS B60. This page is published from the official record of the standard held by the Chinese standards administration: the identification, the dates, the classification and the issuing body are taken from there. The clause text, the tables and the numeric limits are in the document itself, which is delivered complete in English translation.

GB/T 13942 in this section applies to the determination of antimicrobial exposure conditions in the field of timber damage or termites performance and evaluation Natural durability rating. This section provides the timber in contact with the soil under field conditions, antibiotic-destructive measurement and rating methods.

2 Normative references

The following documents contain provisions which, through reference

GB/T 13942 in this section constitute provisions of this section. For dated reference documents Member, all subsequent amendments (not including errata content) or revisions do not apply to this section, however, encouraged to reach under this section Parties to research agreement to use the latest versions of these documents. For undated reference documents, the latest versions apply to this section.

GB/T 14019 wood preservative term

3 Terms and Definitions

Terms and definitions GB/T 14019 apply to this part of the established GB/T 13942 of.

4 Test site preparation and the sample timber

4.1 Test Site Select a representative from the venue of tropical, subtropical and warm temperate climate zone. The test area shall indicate the location and climate zone. To test site is flat, moderate soil moisture, without drought or waterlogging, soil layers thick, rich in humus. If you choose to termite activity The main venue, six months before the test, as the case may be required to place the right amount of wood termites induce segment to ensure that the venue termite activity and sub Fabric uniformity. Site should be selected not applied pesticides, preservative treated wood test site has not been conducted. After selecting the site should be long-term retention, is not the same batch of samples Should be free to change. Green plants on the field had no effect on the test may grow up to your decline, if too thick, can be manually removed, should not use chemical herbicides. Due to local weather records, which recorded monthly averaged air temperature, humidity, rainfall, sunshine.

4.2 Sample Preparation The test timber shall be marked with the correct species name (Chinese name and Latin name), place of origin and a brief description of the site conditions. And instructions are Natural forests or plantations. Each sample trees shall be selected on the 3 ~ 5 trunk, height intercepted from the chest up of wooden section, whichever Heartwood section. Of heartwood and sapwood difficult to distinguish, the pith taken outside the heartwood. Wood samples should be taken paragraph sawn board sawing, sample size.

a) 25mm × 50mm × 500mm (Figure 1), the sample rectangular cross section, with the long side parallel to the ring;

b) 20mm × 20mm × 300mm [Referring sawing extraction method a)].