（1）综合各种路面结构类型的特性，提出更具体化具有降噪的路面结构组合，

（1）综合各种路面结构类型的特性，提出更具体化具有降噪的路面结构组合，以实现隧道内良好的声学环境。<br>（2）虽然降噪路面较传统路面降噪效果优，但都或多或少存在一定问题。多孔降噪路面因孔隙率大而容易发生堵塞问题，导致易产生松散、剥落等病害，影响其降噪性能，降低路面使用寿命；橡胶沥青生产时产生大量有害气体，影响人健康等。如何解决降噪路面或多或少带来的不可忽视的影响仍是目前亟待研究解决的问题。<br>（3）加强对双层排水降噪路面的长期观测，其具体在使用过程中较单层排水路面、密级配路面的在结构与功能特性上的规律是如何的尚未知。

(1) Based on the characteristics of various types of pavement structures, a more specific combination of pavement structures with noise reduction is proposed to achieve a good acoustic environment in the tunnel.<br>(2) Although the noise reduction effect of road surfaces is better than that of traditional roads, there are still some problems to some extent. Porous noise reduction pavement is prone to blockage due to its high porosity, leading to diseases such as looseness and peeling, which affects its noise reduction performance and reduces the service life of the pavement; The production of rubber asphalt produces a large amount of harmful gases, which affect human health, etc. How to solve the undeniable impact of noise reduction on road surfaces is still an urgent issue to be studied and solved.<br>(3) Strengthening long-term observation of double-layer drainage and noise reduction pavement, it is still unknown how the specific structural and functional characteristics of single-layer drainage pavement and dense graded pavement are observed during use.

(1) Combining the characteristics of various pavement structure types, a more concrete pavement structure combination with noise reduction is proposed to achieve a good acoustic environment in the tunnel.<br> (2) Although the noise-reducing pavement has better noise-reducing effect than the traditional pavement, there are still some problems. Porous noise-reducing pavement is prone to blockage because of its large porosity, which leads to diseases such as looseness and peeling, which affects its noise-reducing performance and reduces the service life of pavement. A large number of harmful gases are produced in the production of rubber asphalt, which affects people's health. How to solve the more or less noticeable influence of noise-reduced pavement is still an urgent problem to be studied and solved at present.<br> (3) Strengthen the long-term observation of the double-layer drainage noise-reducing pavement, and it is unknown how the structure and functional characteristics of the double-layer drainage pavement and dense graded pavement are compared in the use process.