中文摘要：

根据隧道洞口围岩特点，阐述了隧道洞口施工原则和地表预加固技术及适用范围，总结隧道洞口地表预加固技术的应用和进展情况，并在楚雄至大理一级公路大风坝隧道中应用了该项技术，取得预期效果．通过地表预加固措施，可改善围岩物理力学性能，提高围岩的自稳性，缩小围岩松弛区范围，减小围岩对初期支护的压力．锚杆、注浆管可起到悬挂岩土体作用．超前注浆可加固充填坍塌体，封堵地表水下渗通道．

英文摘要：

Construction principles and the technique of advanced reinforcement from ground for tunnel entrance projects are expounded based on surrounding rock characteristics of the tunnel entrances. The application areas and advantages of the technique are analyzed. The application and development trends about the technique are summarized. The technique of advanced grouting from ground was carried out at Dafengba tunnel in Grade 1 highway from Chuxiong to Dali in south-western China and the expected effects were achieved. After the surrounding rock is reinforced by advanced reinforced measurement from ground, its physical and mechanical properties will be improved, its self-stability will be promoted, and its loosen area and pressure on primary support will be reduced. Anchors and grouting tubes can play a role of hanging surrounding rock. Advanced grouting can reinforce and fill the land slide mass, preventing water from seeping into ground.