Study On The Variance Of Wood Structure And Properties Of Catalpa Bungei C.A.Mey

The anatomic properties, physical and mechanical properties of three Catalpa bungei C.A.Mey wood from Lianyungang Forest have been determined systematically by experiments, analyzed and discussed by means of mathematical statistics in order to seek the wood quality characters and the variance regularity. The results are as follows:(1) The average value of anaul ring width was 0.889 mm, the average basic density was 0.418 g/cm3, the difference of anaul ring width and basic density were significant at level of 0.05.(2) The average of fiber length, fiber width, fiber double-wall thickness, ratio of length to width, ratio of thickness to lumen diameter and ratio of lumen diameter to width were respectively 962.16μm, 17.93μm, 7.09μm, 56.72, 0.67, 0.60. The difference of fiber length, the ratio of lumen diameter to width were significant at 0.05 level. The others were slight at 0.05 level.(3) The average of vessel length, vessel width, ratio of length to width were respectively 375.37μm, 19.74μm, 19.01. The difference of vessel length, vessel width, ratio of length to width were slight at 0.05 level.(4) The average of microfibril angle and cysstallinity were respectively 24.48°and 37.61%, the difference of microfibril angle was significant at 0.05 level, but the cysstallinity was slight at 0.05 level.(5) The air-dried density and oven-dried density of wood were 0.628 g/cm3 and 0.499 g/cm3; the tangential, radial and volume oven-dried shrinkage were respectively 5.34%, 4.04%, 9.84%; the tangential, radial and volume air-dried shrinkage were respectively 3.53%, 2.72%, 6.55%; the ratio of tangential shrinkage to radial shrinkage at oven-dried condition and air-dried condition were 1.49 and 1.30; the tangential, radial and volume swelling from oven-dry to air-dry were respectively 1.91%, 1.38%, 3.52%; the tangential, radial and volume swelling from oven-dry to wet were respectively 5.65%, 4.23%, 10.93%;(6) The compressive strength parallel to gain, bending strength, MOE and toughness of wood were respectively 50.10 MPa, 82.37 Mpa, 8.25 GPa, 57.83 KJ/m2.(7) The boundary between the juvenile wood and mature wood was around the age of 41 year. Catalpa bungei C.A.Mey’s integrated intensity value within the range of 111~170MPa is the moderate wood, composite quality factor greater than 2156×105Pa is high quality material.