Temperature inside mats of high-frequency, hot pressed, glued and laminated bamboo

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To obtain variation in the temperature law for glued and laminated bamboo （GLB）, mats were hot pressed during two phases: fast heating and slow heating, with high-frequency at different moisture contents and amount of spreads. A statistical analysis on temperature variation inside the mats was conducted by Microsoft Excel software using ANOVA two-factor with replication analysis at a 95% confidence level. Results showed that when moisture content increased from 6% to 18%, the amount of spread increased from 200 to 300 gm－2, during the first phase, temperature inside the mats increased slowly with increasing moisture content below 12%, amount of spread below 250 gm－2, and pressing time, and increased sharply with moisture content above 12% and amount of spread above 250 gm－2; whereas, during the second phase temperature influence on moisture content and amount of spread inside the mats was very small at all conditions. Also during the second phase, the heating rate of the core layer decreased with an increase in pressing time. Optimum high-frequency hot pressing technological parameters for GLB manufacturing were as follows: amount of spread--300 gm－2, moisture content of bamboo splits--12%, and pressing time--7 min. It mean that temperature inside the mats are satisfactory, is necessary to make high quality of GLB in order to improve the performance of GLB.［Ch, 3 fig. 4 tab. 18 ref.］