壳结构的仿真分析算法是计算力学领域重要的研究内容，是保障我国CAE软件自主开发能力的重要技术。等几何壳分析适应了CAD/CAE融合的需求，但也存在着等参框架下位移场列式带来的闭锁、应力精度差等问题。本项目将拟协调壳结构分析方法推广到基于精确几何模型的仿真框架中，提出无闭锁、高精度的精确几何拟协调壳单元算法。通过几何方程弱化、位移和应变场同时逼近和半解析基函数等技术，有效解决闭锁问题，解决应力求解的效率和精度的矛盾，并对相关理论和算法进行试验验证和应用推广。本项目瞄准壳结构仿真算法这一经典问题，提出创新性的面向CAD/CAE融合的精确几何拟协调壳分析技术，为壳结构的设计-分析一体化提供新颖理论和高效算法。

Numerical simulation of shell structure is an important content of computational mechanics, which is essential to assure the development ability of domestic CAE software. The isogeometric analysis can effectively promote the combination of design and simulation, while which applies the isoparametric framework and have severe locking problems and poor stress results. In this project isogeometric analysis is combined with quasi-conforming method, and an exact geometry based quasi-conforming shell analysis mechanism is proposed. Locking free and high-precision shell elements are obtained through discretization of strain-displacement function, approximation of both displacement and strain and analytical approximations for strain fields. The shell analysis system will be developed and the numerical and laboratory experiments to verify the theory will be carried out. This project aims to provide novel theory and method for CAD based shell analysis, and to get locking free algorithm with high stress precision. The research findings will provide innovative theory for shell analysis and promote the seamless combination of simulation and design.