饱和地基条件下建筑物振动的屏障隔振控制研究

Traffic, machine operations, pile driving and other human activities can generate ground vibrations, which can which can cause distress to adjacent structures and annoyance to residents, and disturb the operation of precision instrument and equipment. Consequently, the isolation of the vibrations has become an important issue in recent years. Generally, these adverse effects of vibrations can be eliminated or prevented by installation of various types of wave barriers, such as open or in-filled trench and multi-row of piles, between the source and the structure to be protected. In the research, the investigation is focused on effects of using wave barriers for the reduction of nearby building vibration response induced by ground motivation in saturated soil. The coupled semi-analytical boudary element method -finite element method (SemiBEM-FEM) algorithmare will be developed for the numerical analysis of the current problem. Unlike most of the previous formulations, this model completely consider the soil-structure interaction effect and directly determines the effect the wave barriers on the structural vibration response. Effect of the model parameters on effectiveness of vibration isolation by wave barriers is investigated and discussed in detail, including the vibration source charactersistic, the installation position of wave barriers, the geometrical and material properties of the barriers, and the type of upper structure and foundation.Finally, the field test will be carried out to verify the actual isolation effectiveness of wave barriers. Finally,combined the results of field test with numerical analysis, the design guidelines for vibration isolation by wave barriers under complex foundation will be brougt forward. By using the couple SemiBEM-FEM, the calculation error in FEM model caused by the truncation of boundary can be eliminated and the difficulty of BEM to simulate building structure also can be avoid.Therefore, the method brought forward in the research can be used to simulate the dynamic interaction between the saturated soil and structures effectively and accurately.

交通、工程施工以及工业生产中动力机器运行等人类活动引起的振动污染日益频繁，不仅干扰邻近居民的正常生活，还会引起邻近建筑物的损失，干扰精密仪器和设备的正常使用。因此，人工振动污染的治理是目前的研究热点之一。 屏障隔振是振动污染治理的一种有效手段，本课题提出运用SemiBEM(半解析边界元法)-FEM耦合方法，研究饱和地基中屏障隔振技术在建筑物振动控制中的应用问题；通过建立振源-饱和地基-屏障-建筑物的数值计算模型，并结合现场试验，研究饱和地基中屏障对建筑物振动的隔振机理，分析影响屏障隔振效果的主要参数，建立饱和地基中屏障隔振的设计准则,为隔振屏障设计提供了理论基础。本课题利用半解析边界元法模拟饱和软土地基，有限元法模拟建筑物，避免了有限元法模型边界截断产生的计算误差，以及边界元法难以分析建筑结构的难题。本课题研究可为饱和地基中土与复杂结构物动力相互作用分析提供一种高效、精确的计算方法。

在地基中设置屏障是人工振动污染治理的一种有效手段，本课题通过数值模拟和现场试验相结合的手段，研究了空沟、填充沟、排孔和排桩对饱和地基上明置基础产生振动污染的主动隔振问题。首先，采用SemiBEM(半解析边界元法)建立了稳态集中荷载作用下饱和地基上明置刚性基础的二维和三维振动计算模型；在此基础上，推导了饱和地基上明置基础-空沟、填充沟二维主动隔振的边界元方程和明置基础—排孔、排桩三维主动隔振的边界元方程。其次，为解决计算规模较大时SemiBEM程序效率不高的问题，基于SPMD并行结构开发了SemiBEM的并行计算方法，大大提高了计算效率。再次，采用编制的SemiBEM程序计算分析了隔振屏障的几何参数、填充沟（排桩）材料参数、屏障距振源的距离等因素对屏障主动隔振效果的影响。为验证隔振屏障的实际隔振效果，进行了空沟和排孔的现场主动隔振试验，结果表明实际工程中空沟具有更好的隔振效果。最后，运用SemiBEM(半解析边界元法)-FEM耦合方法，建立了明置基础—饱和地基—屏障—建筑物的数值计算模型，推导了屏障对建筑物振动隔振控制的SemiBEM-FEM耦合方程，并开发了相应的计算程序，由于模型前处理工作较为复杂、计算规模较大，屏障对建筑物的隔振控制问题的研究工作正在进行。综合上述成果，本研究为饱和地基中屏障对明置基础振动影响的主动隔振控制问题奠定了坚实的工作基础，同时为建筑物的振动控制提供了一种可行的手段。本项目已撰写完成5篇论文，正在投稿外审中。培养硕士生3名，其中1名已经取得硕士学位，2名在读。项目投入经费25万元，支出16.5476万元，各项支出基本与预算相符。剩余经费8.4524万元，剩余经费计划用于本项目研究后续支出。