工字钢也称为钢梁（英文名称IBeam)，是截面为工字形状的长条钢材。工字钢分普通工字钢和轻型工字钢，H型钢三种。工字钢广泛用于各种建筑结构、桥梁、车辆、支架、机械等。I-steelbeam(alsoknownasEnglishnameIBeam),isanH-shapedsteelstripsection.I-steelisdividedintothreekinds:ordinaryI-steelandlightI-steel,Htypesteel.I-steeliswidelyusedinvariousarchitecturalstructures,bridges,vehicles,stents,machineryandsoon.板材是指一般的压型钢板\平板等,都是较薄的钢板,通常都作为屋面或围护墙等用型材是指热轧的\冷弯的如工字钢\H钢\C型钢Z型钢,通常都作主结构用。Platereferstothegeneralprofiledsteelplate,flatplate,etc.,whicharethinsteelplates,usuallyusedasroofingorretainingwalls.Profilesrefertohotrolledcold-formedones,suchasI-steel,\Hsteel,\CsteelandZsectionsteel,whichareusuallyusedformainstructure.①胶合板有正反面的区别。挑选时，胶合板要木纹清晰，正面光洁平滑，不毛糙，要平整无滞手感。②胶合板不应有破损、碰伤、硬伤、疤节等疵点。1.thedifferencebetweentheplywoodandtheandnegativesides.Whenselecting,plywoodshouldbeclear,***ooth,***ooth,and***ooth.2.Plywoodshouldnotbedamaged,bruised,hardorscarred.)