GB/T 1935-2009Method of testing in compressive strength parallel to grain of wood (English PDF)

Foreword

The standards with international standards ISO 3787. "Test methods for wood along the grain compressive stress limit of determination" in 1976 for the degree of consistency Non-equivalent.

This standard replaces GB/T 1935-1991 "Test Method for Compressive Strength of wood along the grain." this standard compared with GB/T 1935-1991 The main changes are as follows.

--- Delete the first sentence of 5.3, 5.3 will read. "for the production of sample strips of test material from the continuous intercept bark inwardly north-south direction, press Leave enough sample size and shrinkage allowance. "

--- The 6.2 "that is clearly tester pointer return date accurate to 100N", read. "That is obvious pointer tester Returned or load figures show a significant decrease. The record breaking load, load allows the measured accuracy of 100N. "

--- Remove Appendix A.

--- 6.3 will read as follows. "After the destruction of the sample, T 1931-2009 Determination of moisture content of a sample of the entire sample reference GB /." this standard was proposed by the State Forestry Administration.

This standard by the National Standardization Technical Committee timber.

1 Scope

This standard specifies the determination of compressive strength parallel to the grain of the wood test equipment, samples, test procedures, the results of the calculation and the test report.

This standard applies to small wood unblemished specimens compressive strength test parallel to grain.

2 Normative references

The following documents contain provisions which, through reference in this standard and become the standard terms. For dated references, subsequent Amendments (not including errata content) or revisions do not apply to this standard, however, encourage the parties to the agreement are based on research Whether the latest versions of these documents. For undated reference documents, the latest versions apply to this standard.

GB/T 1928-2009 physical and mechanical test methods - General GB/T 1929-2009 physical and mechanical test materials and test specimens sawing method GB/T 1931-2009 Method for determination of moisture content of wood Principle 3 Direction along the grain of wood to a uniform rate of pressure to destroy, to determine the compressive strength parallel to the grain of wood.

4 Test Equipment

4.1 test machine, load measurement accuracy should meet the requirements GB/T 1928-2009 Chapter 6, and has a spherical plain bearings.

4.2 Test Gauge Measurements shall be accurate to 0.1mm.

4.3 GB/T 1931-2009 Chapter 3 test equipment requirements.

5 Sample

5.1 test material sawing and test specimens were according to GB/T 1929-2009 the provisions of Chapter 3.

5.2 Sample size is 30mm × 20mm × 20mm, a length along the grain direction. Tone sample preparation requirements and inspection, the sample moisture content Whole, were referring to GB/T 1928-2009 Chapter 3 and Chapter 4 requirements.

5.3 for the production of sample strips of test material from the continuous intercept bark inwardly north-south direction, according to the sample size and leave enough shrinkage allowance.

6 Test procedure

6.1 In the central sample length, width and thickness measurements, accurate to 0.1mm.

6.2 The sample at the center of the spherical bearing activities of the testing machine, at a uniform rate of loading within the sample broken 1.5min ~ 2.0min Bad, that tester pointer returned or significant figures show a significant reduction in the load. The record breaking load, load allows the measured accuracy 100N.

6.3 destruction of the sample, the entire sample reference GB/T 1931-2009 Determination of the moisture content of the sample.

7 Results Calculation

The aqueous sample was 7.1 W when the compressive strength parallel to grain, shall be calculated the formula (1), accurate to 0.1MPa.

sigmaW =

Pmax