材料力学教材(PDF)_clfle

1、2-12-22-32-42-52-62-72-83-13-23-33-43-53-63-73-83-93-103-113-123-13习题答案第二章轴向拉伸与压缩bi_i=35MPa,兔2=63.7MPa； b) bi_i=-63.7MPa,兔2=-31.8MPa。Z=0.043mm。F=17.25kNo75.4mm2；(2) 56.8mm2。E=2.08X 105MPa, =-2.52 X 10-3mm。l=6.67mm；尸119.6MPa。G=20kN.0=26.6。第三章 材料的力学性质 拉压杆的强度计算伍=233MPa,册=405MPa,沪27.5%, 旷58.8%。&=1.51X10

2、-3,环=60X10-3。d=18.31mm。8232 天。t=33.18oC,严15.45MPa。EE2 A】 (a 2 - a. )T 6 2 =E A + E 2 A?E E2 A2 (a 2 - a! )76 =E A + E 2 A?Gmax=58.3kN。右6.18mm,尸=108mm。0=45。Fn 1= Fn2=0.828F。6=6= 100.7MPa。6P7(略)3-143-154-14-24-34-44-54-64-74-84-94-104-114-124-135-25-35-45-75-8Fq=46.2ZTQ=112MPa,册s=141MPa, b)。(略)a) e :t

3、2bh tb3 +12罠b) e.2b 2 + 2nrb + 4r 2 4b +nrM1 =-洛Mo = M3 = 138kN m, M、= M2 = 635kN m。(1) B=100mmoIg = 3.67xl05mm4(yG = 23.3mm)。6=3=19.1MPa,=22=27.2MPa。13 bfr=1.58MPa, CJs=18.9MPao14 cJs=43.3MPa bj=6.47MPa。第七章应力与应变分析1 a)兀=62.5MPa, Ta=21.6MPa, omax=100MPa。ba=27.3MPa, Ta =27.3MPa, max=14.64MPa。ba=52.3MP

4、a, Ta =T8.7MPa, cjmax=62.36MPao2 bi=80MPa, =40MPa,仍=0。3 bi=120MPa, f2Fa38Fa3CV =9EI BC = 3Ero(1) C =込型，Ga =込型； AV =竝(3a + h)。 C8hA2h曲 h=1 Fl = 8+3 羽 FlA = 3(1+73)ET AV = 9(1+73)貢10-2310-2410-2510-2610-2710-2810-2910-3010-3110-3210-3310-3410-3510-3611-211-3比=0.020a)=0.005 13FL,EIMmax =-0.101 2Fl.b) S

5、C = 0.005 13(F + q皓,maxfrb5FS166EIl3Fni = Fn2 = Fn4 = 0.396F Fn3 =-0.604F Fn =-0.561F Fn = 0.853F。A=Q水平反力为F/na)Fnc=巻 MC=72 八b)fbh=fdh=誓;c) Fah = 2.23kN FAv = 12.5kN ； d) Fqe = 0.63F,坨=0.28FI。7当 a=l 时有 X = Fl oaGI p + 2lEI4(aGIp + lEI)第一章压杆稳定F =血Fcr = EAsin2acosa。11-4F =3n2EI4l2。11-59 =arctan(cot2 )。

6、11-6n3 Ed 412812 11-7n3 EI12。11-8聞 kl = f )11-9=7.5kN。11-10=345kN。11-11=857kN。11-12T=46.6o。11-13=118.8kN。11-14=898kN。11-15a =19.4cm。11-16dAC:=24.2mm, db(kl 。c = 37.2mm 。附录A平面图形的几何性质A-1a)2R sin 况3a(n +1)bh 、h(2a+b)XC =石厂yC =忌；C)yC = 3(a + b)d)yc = 65mm ；e)yc = 141mm ；a 5af)yc =6 = xcA-2a)T bh3 ix T x

7、 = IT； b) I*2 ah 315A-3c)I(a 2 + 4ab + b2)h3xC -36(a + b)d)Ixc =1.172xl03cm4 ；e) 1曲=4.45x10-5m4f)I = 5a 4 xC =A-4】xC =(9n2 - 64)R 472nA-5Ix =盅-b (d-t)2, Iy =出-bx 644y 6412A-6 a=12.56cm。A-7 a)Ix =瞥，Iy =譽，Ixy =誓；b)Ix = Iy = 0.56xl05mm4, = 0.775xl05mm4。A-8 a) yc = 0.885 I*c = 10.47丫b) yc = 103mm, I*c = 3.91xl07mm4。c) yc =