利用边界元法研究声屏障屏体吸声性能布局对道路双侧声屏障插入损失的影响。对于由全反射屏体和全吸声屏体组合而成的声屏障，当两种具有不同吸声性能屏体的面积比相等时，在全吸声和全反射屏体两等分的情况下，屏体布局在多数受声点对于线性声级插入损失基本没有明显区别；在全吸声和全反射屏体四等分的情况下，插入损失最高的布局相对于插入损失最低的布局的改善量最高可达1.5 dB。计算得出，声屏障迎声面上部与底部的屏体吸声性能对声屏障的插入损失影响最大，屏体上部与底部为全吸声的布局总是具有最高的插入损失，而在上部与底部这两部分中，靠近上部屏体的吸声性能对声屏障插入损失改善的影响要比底部屏体更占主要作用。%BEM is introduced for prediction of insertion loss of hybrid parallel noise barriers with different arrangement of absorptive and reflective façades. In the situation that the area ratio of sound absorptive façade to sound reflective surface of the barrier is 1:1, no distinct difference of the linear sound level insertion losses for different arrangements can be observed as the surface is equally divided into two parts. While the improvement of the insertion loss among the four arrangements can reach 1.5 dB as the surface is equally divided into four parts. The insertion loss of the hybrid noise barrier is mainly affected by the sound absorptive characteristics of the upper and lower parts of the surface. The noise barrier with upper and lower sound absorptive surfaces always has the highest insertion loss. The sound absorptive characteristic of the upper part of the hybrid noise barrier has larger influence than the lower part on the improvement of the insertion loss.
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