[The Mechanical Properties of Wood by Samuel J. Record]@TWC D-Link bookThe Mechanical Properties of Wood PART III TIMBER TESTING[56]
[Footnote 56: The methods of timber testing described here are
for the most part those employed by the U 65/101
Care should be taken to avoid as much as possible the storage of green material in any form. _Air-dry material_: The material to be air-dried will be cut into sticks 2-1/2" X 2-1/2" X 4'.
The ends of these sticks will be paraffined to prevent checking.
This material will be so piled as to leave an air space of at least one-half inch on each side of each stick, and in such a place that it will be protected from sunshine, rain, snow, and moisture from the ground.
The sticks will be surfaced and cut to length just previous to test. _Order of Tests_ The order of tests in all cases will be such as to eliminate so far as possible from the comparisons the effect of changes of condition of the specimens due to such factors as storage and weather conditions. The material used for determining the effect of height in tree will be tested in such order that the average time elapsing from time of cutting to time of test will be approximately the same for all bolts from any one tree. _Tests on Green Material_ The tests on all bolts, except those from which a comparison of green and dry timber is to be gotten, will be as follows: _Static bending_: One stick from each pair.
A pair consists of two adjacent sticks equidistant from the pith, as _N_7 and _N_8, or _H_5 and _H_6. _Impact bending_: Four sticks; one to be taken from near the pith; one from near the periphery; and two representative of the cross section. _Compression parallel to grain_: One specimen from each stick. These will be marked "1" in addition to the number of the stick from which they are taken. _Compression perpendicular to grain_: One specimen from each of 50 per cent of the static bending sticks.
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