地铁所致某音乐排练厅室内二次结构噪声测试与仿真

近年来,随着地铁建设的迅速发展,地铁运行时所产生的振动对邻近建筑室内的二次结构噪声影响逐渐引起人们的关注。为研究室内二次结构噪声数值预测方法,以北京地铁某正线邻近二层音乐排练厅为例,首先对建筑墙、楼板的振动及室内噪声状况进行多点同步详细测试,通过实测数据分析得到地铁运行所致建筑室内振动及二次结构噪声特性;然后采用大型有限元软件Ansys建立隧道-岩土-建筑-声场三维精细化数值仿真模型,对地铁列车通过时的室内二次结构噪声进行仿真计算,并与实测数据进行对比分析。结果表明:地铁列车运行引起的建筑室内二次结构噪声在63 Hz处出现峰值;在100 Hz以下频率范围内仿真结果与实测结果吻合较好;受模型网格划分尺寸影响,100 Hz以上振动和二次结构噪声数值计算结果小于实测值,考虑到地铁运行引起的振动频率主要分布在1 Hz至100 Hz范围内,其对100 Hz以上的振动及二次结构噪声影响相对较小,因此可认为所采用的数值计算方法是科学可靠的,可为类似地铁沿线建筑室内二次结构噪声预测评价提供参考。

Test and Simulation Analysis of Ground-borne Noise in a Rehearsal Hall Caused by Subway Operation

With a rapid development of rail transportation, Ground-borne noise induced by passing-by trains addresses serious public concern. In order to research the Ground-borne noise by numerical simulation method, this paper takea rehearsal room beside two subway lines in Beijing as a example. Initially, a series of vibration tests on structural floors and walls have been conducted, and the sound pressure at the room center has been simultaneously measured. The characteristics of the vibration and the ground-borne noise caused by trains are summarized. Moreover, a coupled 3D finite element model of the tunnel, soil, and structure is established along with the acoustic field to study the ground-borne noise and its distribution in space. The comparison between test data and numerical data shows that the numerical data is agree with the test under 100Hz, and particularly, a peak is found at 63Hz in both results. Above 100Hz, however, difference is found between them because of the mesh size which needs to be finer for the simulation at higher frequencies (above 100 Hz). As the vibration caused by passing-by trains is usually in the range of 1-100Hz, the simulation in this paper is appropriate and has sufficient accuracy. The proposed model provides a reference for similar cases in the prediction of the ground-borne noise induced by passing-by trains.