Do You Always Adjust Test Results to 12 Percent Moisture Content? No!

作者：Patterson David W^*; Hartley Jonathan I

来源：Forest Products Journal, 2013, 63(3-4): 125-127.

After conducting mechanical tests, the moisture content (MC) of the test specimens is determined. If the MC is not 12 percent, the standard procedure is to adjust the test value to equal those at 12 percent MC. With new treatments such as high-temperature heat treating, however, 12 percent MC may not be an appropriate value for adjustment. Tests were conducted using three species (southern pine [Pinus taeda], red oak [Quercus sp.], and sweetgum [Liquidambar styraciflua]), three temperatures (100 degrees C, 150 degrees C, and 200 degrees C), and three conditioning environments (conditioning chamber, outside air, and enclosed over water). The results indicated that the higher the treatment temperature, the more difficult it was to reach 12 percent MC. For example, the MC of the samples treated at 200 degrees C in the conditioning chamber was 7 or 8 percent, whereas the MC of the controls was 13 percent. These results imply that adjusting test values to 12 percent MC would be inappropriate if all specimens were conditioned in the same environment.

• 出版日期2013