浮式平台补充2.ppt

浮式结构设计基础 2008年5月 第二章　浮式结构强度分析 www.DeepWaterC 浮式结构设计基础 2008年5月 第二章　浮式结构强度分析 第二节 设计原理 与结构总强度分析 Design Principles and Global Structure Analysis 一. Introduction to Design Theory Design can be described as the process of conceptually creating something that does not yet exist More than one feasible design ； A set of design variables； Satisfies the performance criteria (or constraints)； Some are “better” than others—optimum design； Another significant feature of design is the it is an iterative process. bjective function, for compare of feasible design . Design Optimization Minimize or Maximize fobj(dv1,dv2,dv3, ... ,dvn) subject to: fconstraint_1(dv1,dv2,dv3, ... ,dvn) compared to allowable value fconstraint_2(dv1,dv2,dv3, ... ,dvn) compared to allowable value fconstraint_3(dv1,dv2,dv3, ... ,dvn) compared to allowable value ..... fconstraint_m(dv1,dv2,dv3, ... ,dvn) compared to allowable value Where fobj = the objective function; dvi = the ith design variable n = number of design variables ; fconstraint_i =the ith constraint function; m = number of constraint functions Design vs Analysis Two separate activities 1. Analysis is the evaluation of a defined pro 2. The process of design uses the results of analysis to make decisions about the problem description.blem.? 3. In steel design, this means that being proficient using spreadsheets, MathCad, or other computer based computational tool becomes extremely useful.? Computers are particularly useful in handling repetitive tasks. Design Codes and Specifications 1. To minimize the possibility of failures, we constantly learn from the professions experience.? 2. The design codes and specifications are the means that society and the profession use to help prevent reoccurrence of the failures of the past.? 设计原理与方法—ASDLRFD 概念：