材料力学双语教学学习资料.docx
《材料力学双语教学学习资料.docx》由会员分享,可在线阅读,更多相关《材料力学双语教学学习资料.docx(25页珍藏版)》请在冰点文库上搜索。
![材料力学双语教学学习资料.docx](https://file1.bingdoc.com/fileroot1/2023-6/19/f84f2bca-5f81-4f53-9377-879cb055e964/f84f2bca-5f81-4f53-9377-879cb055e9641.gif)
材料力学双语教学学习资料
材料力学双语教学学习资料1
第一章绪论
Chapter1Introduction
§1-1材料力学的任务
TheTasksofMechanicsofMaterials
1*.材料力学:
MechanicsofMaterials
2.构件:
StructuralMembers
3.变形:
Deformation
4*.强度:
Strength
5*.刚度:
Rigidity
6*.稳定性:
Stability
§1-2变形固体的基本假设
FundamentalAssumptionsofSolidDeformationBodies
1.连续性假设:
Continuity
2.均匀性假设:
Homogeneity
3.各向同性假设:
Isotropy
§1.3外力及其分类
ExternalForcesandClassification
1.分布力:
DistributedForce
2.集中力:
PointForce
3.静载荷:
StaticLoad
4.动载荷:
DynamicLoad
§1.4内力、截面法和应力的概念
ConceptsofInternalForces,MethodofSectionandStress
1*.内力:
InternalForce
2*.截面法:
MethodofSection
3.截面法的三个步骤:
截开,代替,平衡
Threestepsofmethodofsection:
cutoff,substitute,andequilibrium.
4*.应力:
Stress
5.平均应力:
Averagestress
6.应力(全应力):
Wholestress(sumstress)
7*.正应力:
NormalStress
8*.剪应力(切应力):
ShearingStress
§1.5变形与应变
DeformationandStrain
1.线应变:
Strain
2.剪应变:
ShearingStrain
§1.6杆件变形的基本形式
BasicTypesofDeformationsofRods
1*.拉伸或压缩:
TensionorCompression
2*.剪切:
Shear
3*.扭转:
Torsion
4*.弯曲:
Bending
第二章拉伸、压缩与剪切
Chapter2Tension,CompressionandShear
§2.1轴向拉伸与压缩的概念和实例
TheConceptandExamplesofAxialTensionandCompression
1.拉杆:
TensileRod
2.压杆:
CompressiveRod
3.受力特点:
外力合力的作用线与杆轴线重合CharacteristicoftheExternalForces:
Theactinglineoftheresultantofexternalforcesiscoincidedwiththeaxisoftherod.
4.变形特点:
杆沿轴向伸长或缩短
CharacteristicofDeformation:
Rodwillelongateorcontractalongtheaxisoftherod.
§2.2轴向拉伸或压缩时横截面上的
内力和应力
InternalForceandStressofAxialTensionorCompressionontheCrossSection
1*.横截面:
CrossSection
2*.轴力:
NormalForce
3*.轴力图:
DiagramofNormalForce
§2.3直杆轴向拉伸或压缩时斜截面上的应力
StressofAxialTensionorCompression
ontheSkewSection
1.斜截面:
SkewSection
2.
§2.4材料在拉伸时的力学性能
MechanicalPropertiesofMaterials
withTensileLoad
1.标准试件:
Specimen
2.低碳钢(C≤0.3%):
LowCarbonSteel
3.弹性阶段:
ElasticRegion
4.屈服阶段:
YieldingStage
5.强化阶段:
HardeningStage
6.颈缩阶段:
NeckingStage
7*.σp----比例极限:
ProportionalLimit
8*.σe----弹性极限:
ElasticLimit
9*.σs----屈服极限:
YieldingStress
10*.σb----强度极限:
UltimateStress
11.延伸率:
PercentElongation
12.断面收缩率:
PercentReductionofArea
13.塑性材料:
DuctileMaterials
14.脆性材料:
BrittleMaterials
15.铸铁:
Castiron
§2.7失效、安全系数和强度计算
Failure,SafetyfactorandStrengthcalculation
1*.许用应力:
AllowableStress
2.安全系数:
SafetyFactor
3*.强度条件:
StrengthCondition
4*.强度校核:
Checkstrength
5*.截面设计:
Sectiondesign
6*.确定许可载荷:
Determineallowableload
§2.8轴向拉伸或压缩时的变形
DeformationinAxialTensionorCompression
1.弹性变形:
ElasticDeformation
2.塑性变形:
PlasticDeformation
3.纵向应变:
LongitudinalStrain
4.横向应变:
LateralStrain
5.线弹性变形:
LinearElasticDeformation
6.泊松比:
Poisson’sratio
7*.弹性模量-E:
表示材料抵抗拉压变形的
能力E-modulusofelasticity:
Indicatesthecapabilityofmaterialsforresistingtensionorcompression
8*.抗拉刚度-EA:
表示构件抵抗拉压变形的能力EA-theaxialrigidity:
Indicatesthecapabilityofconstructivemembersforresistingtensionorcompression
9*.胡克定律(Hooke’sLaw):
当应力不超过材料的比例极限时,应力与应变成正比.Thestressisproportionaltothestrainwithintheelasticregion.
§2.12应力集中的概念
TheConceptofStressConcentration
1.由于截面尺寸的突然变化,使截面上的应力分布不再均匀,在某些部位出现远大于平均值的应力,称应力集中。
Discontinuitiesofcrosssectionmayresultinhighlocalizedorconcentratedstresses.
2.理论应力集中系数K:
TheoreticalStress-concentrationFactor-K
§2.13剪切和挤压的实用计算
PracticalCalculationofShearandBearing
1*.剪切:
Shear
2.剪切面:
ShearingPlane
3*.剪切面上的内力-剪力:
InternalForceinShearingPlane-ShearingForce
4.剪切的实用计算:
PracticalCalculationofShear
5.挤压的实用计算:
PracticalCalculationofBearing
6.挤压强度条件:
工作中的挤压应力不应超过许用挤压应力。
Strengthconditionofbearing:
Workingbearingstressshouldnotexceedthe
allowablebearingstress.
第三章扭转
ChapterThreeTorsion
§3.1扭转的概念和实例
ConceptandExamplesofTorsion
1.电动机:
Generator
2.涡轮:
Turbine
3*.扭转的受力特点:
杆件的两端作用着大小相等,方向相反,且作用面垂直于杆件轴线的力偶。
Characteristicofloads:
Shaftisloadedbyatorsionalcoupleinplanesthatareperpendiculartotheaxisoftheshaft.
4*.变形特点:
杆件的任意两个横截面发生绕轴线的相对转动。
Characteristicofdeformation:
anytwocrosssectionswilltwistalongtheaxis.
5*.轴:
Shaft
§3.2外力偶矩的计算扭矩和扭矩图
Calculationoftheexternaltorque
InternaltorqueandItsdiagram
1.扭转外力偶矩的计算:
Calculationoftheexternaltorque
2*.扭矩:
InternalTorque
3.符号规定:
Signconvention
4*.右手螺旋法则:
Righthandscrewrule
5*.扭矩图:
DiagramofInternalTorque
§3.3纯剪切
PureShear
1.薄壁圆筒的扭转实验:
Experimentofthin-walledcirculartubeundertorsion
2.变形特点:
Charactersofdeformations:
截面间的距离不变;所有横截面的位置不变;所有纵向线转过了一个角度γ。
Distancesbetweenthesectionsremain
unchanged,Allcrosssectionsremainunchanged,Allthegeneratinglinesrevolvethroughanangleγ.
3*.切应力互等定理:
Theoremofcomplementaryshearingstresses
4*.切应变:
Shearingstrain
5*.剪切虎克定律:
Hooke’slawofshear
6*.剪切弹性模量G:
Modulusofelasticityofshearing
第四节圆轴扭转时的应力
Stressesinaroundshaftundertorsion)
1*.Ip(极惯性矩)---polarmomentof
inertia
2*.Wp(抗扭截面系数)----sectionmodulus
intorsion
§3.5圆轴扭转时的变形
1.扭转角:
Theangleoftwist
2*.抗扭刚度GIp:
thetorsionalrigidity
3*.扭转的刚度条件:
Rigidityconditionintorsion
4.单位长度扭转角:
Theangleoftwistperunitlength
Exercises
1.Abracket(支架)isshowninthefigure,Thecross-sectionareaofthesteelbarABisA1=6cm2;thecross-sectionareaofthewoodenbarBCisA2=300cm2,Knowingtheallowablestressofsteelis[σ]=140MPa,theallowabletensilestressofwoodis[σ]L=8MPa,andtheallowablecompressivestressofwoodis[σ]Y=4MPa.TrydeterminetheallowableloadPofthebracket.
2.Awoodentenon(榫)jointisshowninthefigure.Knowingthatthequantitiesarea=b=12cm,h=35cm,c=4.5cmandP=40KN.Trytodeterminetheshearingstressandbearingstressforthejoint.
3.Twoboardsareboltedtogetherasshown.Eachboardhasathickness(δ)of2mm,andawidth(b)of15mm.Thediameterdoftheboltis4mm.Allthepartsaremadefromthesamematerialandhavethesameallowablestresses
160MPa,
=100MPa,
300MPa.TrytodesignthetensileforceF.
4.Atensilebarandtwocoverboardsareboltedtogetherasshown.Eachcoverboardhasathicknessof8mm.Allthepartsaremadefromthesamematerialandhavethesameallowablestresses
80MPa,
=60MPa,
160MPa.Thethicknessofthebar
=15mm,thetensileforceF=120KN.Trytodesign
(1)thediameterdofthebolt.
(2)thewidthbofthetensilebar.
5.构件在外力作用下抵抗破坏的能力称为;构件在外力作用下抵抗变形的能力称为;构件在外力作用下保持原有平衡状态的能力称为。
(PleasefillintheblankswithproperwordsinEnglish.)
6.杆件的基本变形一般有 、 、
、 、四种。
(PleasefillintheblankswithproperwordsinEnglish.)
第四章弯曲内力
ChapterFourInternalForcesinBending
§4-1弯曲的概念和实例
§4-1TheConceptsandExamplesinBending
1*.梁:
beam
2.轴线:
axis
3.纵向对称面:
longitudinalplaneofsymmetry
4*.平面弯曲:
planebending
5*.弯曲的受力特点:
作用于杆件上的外力或外力偶矩矢垂直于杆件轴线。
Characteristicsofloads:
externalforcesorexternalthecouplevectorperpendicular
totheaxisoftherod.
6*.弯曲的变形特点:
杆件的轴线由直线变为曲线。
Characteristicsofdeformations:
theaxisoftherodchangeintocurvefromoriginalstraightlines.
7*.弯曲变形:
杆件在垂直于杆轴线的外力或两个外力偶的作用下,杆的轴线由直线变为曲线,这种变形称为弯曲变形。
BENDING:
Theactionoftheexternalforceorexternalthecouplevectorperpendicular
totheaxisoftherodmakestheaxisoftherodchangeintocurvefromoriginalstraightlines,thisdeformationiscalledbending.
§4-2受弯杆件的简化
§4-2SimplificationofBendingRods
1.集中力:
concentratedforce
2.分布力:
distributedload
3.均布载荷:
uniformload
4.支座:
support
5*.简支粱:
simplesupportedbeam
6*.外伸梁:
overhangingbeam
7*.悬臂梁:
cantileverbeam
§4-3剪力和弯矩
§4-3ShearingForceandBendingMoment
1.弯曲内力:
internalforcesinbending
2*.剪力:
shearingforce
3*.弯矩:
bendingmoment
4.内力的正负规定:
signconventions
fortheinternalforces
§4-4剪力方程和弯矩弯矩方程
剪力图和弯矩图
§4-4TheEquationsofShearingForceandBendingMoment
TheDiagramsofShearingForceandBendingMoment
1*.剪力方程:
equationofshearingforce
2*.弯矩方程:
equationofbendingmoment
3*.剪力图:
diagramofshearingforce
4*.弯矩图:
diagramofbendingmoment
§4-5载荷集度、剪力和弯矩间的关系
§4-5RelationsamongtheIntensityofDistributedLoad,ShearingForceandBendingMoment
1*.微分关系:
differentialrelations
2*.规律法:
methodofregulation
3*.控制截面法:
methodofcontrolsections
4.水平直线:
horizontalstraightline
5.斜直线:
inclinedstraightline
6.突变:
suddenchange
7.增函数:
increasingfunction
8.减函数:
decreasingfunction
9.盆状抛物线:
basin-likecurve
10.坟状抛物线:
tomb-likecurve
11.折向与P相反:
flexibleoppositetoP
第五章弯曲应力
ChapterFiveStressesinBending
§5-1纯弯曲
§5-1PureBending
1.横力弯曲:
transversebending
2*.纯弯曲:
purebending
3.平面假设:
横截面变形后仍为平面,只是绕中性轴发生转动,距中性轴等高处,变形相等。
Hypothesisofplanesection:
Thecrosssectionsremainstillplanes,andonlyrotatethroughsomeanglesaroundtheirneutralaxesafterdeformation.
4*.中性层:
neutrallayer
5*.中性轴:
neutralaxis
6.纵向对称轴:
longitudinalaxisofsymmetry
§5-2纯弯曲时的正应力
§5-2NormalStressinPureBending
1.几何关系:
geometricrelation
2.物理关系:
physicsrelation
3.静力关系:
staticrelation
4*.抗弯刚度EIz:
flexuralrigidity
§5-3横力弯曲时的正应力
§5-3NormalStressinTransverseBending
1*.抗弯截面系数W:
sectionfactorofbending
2*.弯曲的强度条件:
strengthconditioninbending
§5-4弯曲切应力
§5-4ShearingStressinBending
1.矩形截面梁:
thebeamwithrectangular
section
2.工字形截面梁:
wide-flangebeam
3.翼缘:
flange
4.腹板:
web
5.静矩:
staticmoment
6*.惯性矩:
momentofinertia
6.焊接:
melt
7.铆接:
rivet
§5-6提高弯曲强度的措施
§5-6MeasuresofIncreasingStrengthinBending
1.合理安排梁的受力情况:
arrangetheloadsofbeamreasonably
2.跨度:
span
3.梁的合理截面:
reasonablesectionofbeams
4*.等强度梁:
equalstrengthbeams
第六章弯曲变形
ChapterSixDeformationsinBending
§6-1工程中的弯曲变形问题
§6-1TheProblemsofDeformationDuetoBendinginEngineering
1.车床主轴:
principalaxisoflathe
2.振动:
vibrate
3.噪声:
noise
§6-2挠曲线的微分方程
§6-2