随着经济的快速成长，交通运输也随之蓬勃发展，其中交通运输时间的缩短及运输燃料的节省更为重要，又因工程技术及材料的提升，因而促使隧道工程成为工程规划及设计上的首选，其虽可能导致工程经费的增加，但却大幅缩短运输时间及能源损耗，并增加行车舒适性，对于社会效益之提升具有相当大之帮助。隧道的利用首在确保其畅通性，除隧道内部的结构设计需抵抗地层应力，以维护隧道安全及空间利用外，山岳隧道洞口上方之边坡防护尤为重要，盖因洞口的防护除攸关隧道两端的通畅性外，另与隧道灾变后之救灾与人员逃生有绝对相关。一般隧道洞口的设计及施工均无可避免地对隧道洞口上方边坡稳定性及地表植被产生造成一定程度的影响，若采用喷浆或混凝土框梁等护坡方式时，对生态及环境将产生永久性的影响。预应防护网工法为可取代上述传统混凝土工法且无其缺点的一种新型护坡工法，将可使隧道洞口的设计及施工更加弹性及符合环境保护目的，本文旨在介绍该设计及施工更具弹性、非混凝土结构护坡方式且无需砍伐树木的护坡新工法，以供工程界于设计及施工时之参考。

It is important to shorten transportation time and to save fuel. Tunnel planning and designing is the first choice for the upgrade of engineering technologies and materials and the reason mentioned above. Although tunnel engineering may led to cost increasing, but it can sharply shortened the transport time and reduce the energy loss and increase the driving comfort rate, and it can help the social benefits a lot. Tunnels should be unrestricted. The structure design of the tunnel should meet the requirement of ground stress, so as to keep the tunnel safe. As a result, the protection of slope at tunnel entrance, which can guarantee the patency of the tunnel and can provide escape passage when disaster occurs, is important. Influence of normal tunnel entrance design on slope stability and plants can not be avoided, and internal destroy would be occurred when using shotcreting and concrete frame. Prestressed protection net is a good choice without disadvantages and no damage will occur.