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梳角窃蠹ptilinus fuscus Geoffroy蛀害杨木。干材表面的蛀孔量(孔/200cm~2)与抗弯强度(kg/cm~2)间呈幂函数曲线相关,y=559.9x-0.2042,x~1=x+l,γ~2=0.7282,相关极显著。蛀毁临限的蛀孔量约为28.8孔/200cm~2。杨木被蛀断时的实际平均蛀孔量为69.68±29.49孔/200cm~2,抗弯强度仅较蛀毀临限下降7.96％左右。在蛀害程度调查中,可按蛀孔量分为5级: 0:无蛀孔; 1:3孔/200cm~2以下; 2:9孔/200cm~2以下; 3:29孔/200cm~2以下; 4:29孔/200cm~2以上。 ptilinus届窃蠹类害虫严重蛀害杨木干材的问题,正日益引起人们的关注。G、NIZI(1974)。B.VERD—COGRT(1980),最近曾先后报导过栉角窃蠹(P.pectinicomis L.)使农舍房梁折断及发现于杨树枯枝上羽化等害例。然而,在我国青海农村,梳角窃蠹P.fuscus Geoffroy则每年毁塌民房逾数千间。鉴于以往很少见有关害虫蛀损干材所造成的材性力学现象的详细论述,本文拟从杨木受梳角窃蠹蛀害后的抗弯强度变化上,试分析其蛀损规律。
Ptilinus fuscus Geoffroy The amount of bore hole on the surface of the dry material (hole / 200cm ~ 2) and the flexural strength (kg / cm ~ 2) were power function curve, y = 559.9x-0.2042, x ~ 1 = x + l, = 0.7282, the correlation is extremely significant. The amount of bore holes destroyed is about 28.8 holes / 200cm ~ 2. The actual average bore hole when the poplar was decayed was 69.68 ± 29.49 holes / 200cm ~ 2, and the flexural strength was only 7.96% lower than that of the decay. In the investigation of degree of calamity, it can be divided into 5 grades according to the amount of bore hole: 0: no hole; 1: 3 hole / 200cm ~ 2 or less; 2: 9 hole / 200cm ~ 2 or less; 3:29 hole / 200cm ~ 2 or less; 4:29 holes / 200 cm to 2 or more. The problem of pylostella infesting poplar wood pillars is gaining more and more attention. G, NIZI (1974). B.VERD-COGRT (1980). Recently, it has been reported successively that P.pectinicomis L. broke the beam of the farmhouse and was found to be exuded from the dead branches of poplar trees. However, P.fuscus Geoffroy in rural Qinghai, China, has destroyed thousands of houses every year. In view of the past rarely seen on vermicompost material damage caused by the mechanical properties of a detailed discussion, this paper from the poplar wood combing angle after the decay of the bending strength change, try to analyze the loss of law.