Combining with the factual conditions at Qiandouquan Tunnel project,the paper mainly introduces the comparison between two con-struction schemes for the reconstruction of transverse tunnels into main tunnels,the small pilot drift expanding excavation method and full-enve-lope method,indicates the roof brushing,primary support parameter identification and construction precautions,achieves some meaningful conclu-sion by practice.%结合前陡泉隧道工程实际条件，详细介绍了隧道横洞转正洞“小导洞扩挖法”“大包法”两种施工技术方案，并对挑顶技术、初期支护参数确定以及施工注意事项作了论述，通过实践，得出了一些有意义的结论。
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