中文摘要：

应用VC.net编译平台,开发了邓肯—张模型的DLL动态链接库文件,通过FLAC^3D程序的预留接口导入程序。介绍了邓肯—张模型的基本原理及其在FLAC3D程序中实现的关键技术和具体实现方法。通过对三轴加卸载试验的仿真模拟,分析了试样的Z向和Y向位移变化形态和规律,研究了（σ1-σ3）-εa关系曲线的变化形态,及其在极限情况下曲线的发展规律。从而验证了邓肯—张本构模型在有限差分程序中的准确性和适用性。另外,对一个基坑开挖及其支护过程进行了模拟分析,并通过基坑壁水平位移计算值和监测值的对比,验证了编译的邓肯—张（E-B）模型对工程的适用性,以及应用于其他类似问题的通用性,解决了FLAC2D程序中邓肯—张本构模型（E-B）的应力敏感性及其不能应用于实际工程等问题。

英文摘要：

Duncan-Chang model＇s DLL Dynamic Link Library document is developed by using the debug platform of VC. net, and the model is implanted to FLAC^3D program by the reserved connection of the program. The Duncan-Chang model＇s basic principle is introduced, and the key technologies and the concrete method, which have been realized in the FLAC^3D procedure, are explained. Through numerical simulation of loading and unloading experiment, the change shape and rule of Z and Y displacements for the test specimen are analyzed, and the （σ 1- σ3 ） - εa relationship curve＇s change shape and development rule in the ultimate case are also studied. As a result, it can be concluded that the secondary development of the Duncan-Chang model in finite-difference program has correctness and applicability. By modeling the excavation and retaining of the foundation pit, and comparing calculation horizontal displacements with practical ones, it is found that the Duncan-Chang model （E-B） is adapted to engineering. It also has versatility for using in other similar questions. It can solve the problems in FlAC2D program in which the Duncan-Chang model has sensitivity of stress and inapplicability to the practical project.