Unit10DesignProcessofReinforcedConcrete钢筋混凝土的设计过程ObjectivesofDesign设计任务Thestructureengineerisamemberofateamwhosemembersworktogethertodesignabuilding,bridge,orotherstructurethatwillfulfillthespecificneedsofaclient.Inthecaseofabuilding,anarchitectgenerallyprovidestheoveralllayout,andmechanical,electrical,andstructuralengineersdesignindividualsystemswithinthebuildings.Ageotechnicalorfoundationengineerprovidesinformationnecessaryforthedesignoffoundations,basementwalls,andsoon..结构工程师是以设计满足客户特定需求的建筑，大桥或其他结构为工作的一群人的称呼。在建筑案例中，设计师通常要提供总体布局，机械系统，电力系统，而结构工程师们则设计建筑的个人系统。岩土和地基工程师提供建筑地基设计的必要信息，如地下室墙，等等。Thestructureshouldsatisfyfourmajorcriteria:结构需要满足的四个主要标准：Appropriateness.Thearrangementofspaces,spans,ceilingheights,access,andtrafficflowmustcomplementtheintendeduse.Thestructureshouldfititsenvironmentandbeaestheticallypleasingwhereverpossible.Althoughsuchdecisionsarefrequentlyinthearchitect’sdomain,thestructuralengineershouldbeartheminmindinchoosingframingsystemsforabuildingorinlayingoutstructuressuchasbridges舒适：空间，跨度，天花板高度，入口，交通流必须满足使用目的的要求。结构应该与周围的环境相协调并且尽量满足审美的要求。尽管这些决定经常在建筑师的工作范围之内，但是为了选择建筑框架结构或桥梁铺设结构，结构工程师应该把这些决定牢记在心。Economy.Theoverallcostofthestructureshouldnotexceedtheclient'sbudget.Frequently,teamworkindesignwillleadtooveralleconomies.经济：总花费不应该超过顾客的预算。通过团队设计通常可以算出总预算。3Structuraladequacy.Structuraladequacyinvolvestwomajoraspects:a.Astructuremustbesufficientlystrongtosupportsafely,withoutcollapse,allanticipatedloadings.b.Astructuremustnotdeflect,tilt,vibrate,orcrackinamannerthatimpairsitsusefulness.结构强度：结构强度主要包括两个方面：a．结构必须有足够的强度来保证安全，在所有预先考虑的荷载下不会倒塌。b．结构不能产生损害其使用的倾斜，震动或破裂。4Maintainability.Astructureshouldbedesignedtorequireaminimumofmaintenanceand/ortobeabletobemaintainedinasimplefashion.Itisestimatedthatone-fifthofthehighwaybridgesinNorthAmericaaredangeroustovaryingdegreesbecauseofinadequateattentionduringdesigntodrainage,weathering,orcorrosion,coupledwithinadequatemaintenanceduringtheirlifetimes.可维护性：结构设计应该满足需要最小限度的保养和最简单的方式保养。据估计，北美有五分之一的高速公路大桥处于