Chúng tôi đặt câu hỏi về các inthe gỗ cánh khá thường xuyên ở đây. Có thể là một điều tốt để có trong Tài Handy. Đó là khoảng 200 trang. Tám trang dành cho các bảng nội dung. Tôi đã có bản sao của tôi. | I. I L L c L L L L L I L L I L L r Figure 2-26 Plot ơ equation 2 70 . in which jr _-S tcM gw -ị A EfwEfz b EA1 r a Ej m the number of half-wave lengths in the shape of the buckled panel defined by the inequality m 1 r v Yỉ m 1 Case II. Loaded edges simply supported. Remaining edges clamped. r _4tt2 r 2_j_3 c 9 _ mZ 16 rJ 2_ 2 74 ạ 771 m 1 v 3 r -y m m 1 y3 Ji- A Case III. Two loaded edges clamped. Remaining edges simply supported. For one half-wave 48 T J For two half-waves For three half-waves 2 75 H Ĩ2Õ V v 20t For four half-waves H w r2 Y-344 The value of He that is least for the particular panel involved should be used. Case IV. All edges clamped. For one half-wave ff j 3 4-2i For two half-waves a y 16rM-i L-40fc For three half-waves Ht t2r2 ịÌ4-10i- For four half-waves a 6Y 16r2 136 2 76 68 j L L L L L L L L L L L I L L L L L Figure 2-27. Plot of equation 2 76 . The value QĨHc that is least for the particular panel involved should be used. . Shear fi 0 or 90 . The critical buckling stress of flat rectangular plywood panels subjected to uniform shear stress is given by the following formula ref. 2-50 . F r s. 2 77 in which values of 77 are obtained from figure 2-28 for panels having simply supported edges and from figure 2-29 for clamped edges. The symbols a and b are assigned to the dimensions of the panel . . 1a TyA1 4 1 .1 in such a way that T I IS less than or r 0 ri y equal-to unity. . Combined compression and shear j3 0 or 90 . The critical buckling stresses of flat rectangular panels subjected to combined compression and shear may be obtained by use of the fol lowing interaction formula ref. 2-50 Ay A 1 2 78 in which the ratio of her to jeer is given by the particular problem to be solved. This equation is accurate only for isotropic plates but is not greatly in error for plywood if 3 0 or 90 . . Compression shear and combined compression and shear fi any angle . When the direction of the face grain of the plywood makes an angle other .
