本文在总结国内外拆除爆破发展动态的基础上，对楼房逐段解体爆破拆除方法运用经典力学知识，通过分析结构的失稳原理以及结构失稳后绕固定轴旋转运动规律、结构势能转化规律、应力波在固体中的传播规律，得出了框架结构逐段解体延期时间。 通过分析结构材料的力学本构模型和楼房的爆破特征，利用有限元分析软件ANSYS对框架楼房逐段解体爆破拆除进行数值模拟分析，通过选择恰当的有限元模型，设置合理的材料屈服、破坏准则，得出结构在失稳前的应力、应变、裂缝生成随时间的变化关系以及形成塑性铰的位置。根据结构失稳后旋转运动规律，利用MATLAB软件中simMechanics模块模拟出结构完全破坏后倒塌的运动过程。 最后通过对比分析塑性铰位置结构应力在整个结构解体过程中随时间的变化，得出了逐段解体延期时间与爆轰波在结构中传播时间长短无关的规律，并得出了更为合理的逐段解体延期时间。在ANSYS分析塑性铰形成过程中，根据塑性铰形成时间与加载时间和加载子步的关系，得出了塑性铰形成时间与加载时间成正比而与加载子步多少无关的规律。同时得出，延期时间决定塑性铰形成时间，塑性铰形成时间为确定延期时间提供范围下限。

In this paper, Based on the research state of demolition blasting in our country and out of country. It concluded the delay time by gradual disintegration after used classic mechanics knowledge to analyze the principle of disintegration structure becoming to unstable, the principle of structure rotation about a fixed axis after structure becoming to unstable ,the principle of converting of the structure potential energy and the principle of propagation of stress wave in solid. After analyzed material mechanics constitutive model and structure blasting feature.It adopted finite element method analysis software ANSYS to numerical simulate and analyze the frame-structure buildings by gradual disintegration blasting demolition. Provided that finite element model , yielding and destroy rule of material and solution method were rationally selected .It could conclude that the time relative to stress,strain,crack create and the location of plastic gemes distribute according to the law of rotary movement of structure after employed the simMechanics module in the MATLAB software simulating the motion process after structure destroyed absolutely . The least but not last .The primary conclusions was drawn in this paper that the law of the gradual disintegration delay time was nothing to do with the time of the detonation wave in solid by contrast analyzing the change of the stress at the plastic joint location follow time in the full course of structure collapse. It gained the more rational delay time of gradual disintegration in the course of ansys analysis. It could also conclude that the time of plastic joint form was directly proportional to the load time and was nothing to do with the load substep according to the relation of plastic joint form time and loading time and load substep. Otherwise ,It concluded that the delay time decided the time of plastic joint form and the time of plastic joint form decided the low time of delay time .