東紀州命の道　熊野尾鷲道路最後のトンネルを貫く: 国道42号　新鹿トンネル

摘要

国道42号熊野尾鷲道路は,三重県尾鷲市と熊野市を結ぶ延長18.6kmの自動車専用道路で，紀勢自動車道と一体とな り高速道路ネットワークを形成する道路である.周辺地域の産業開発や世界遺産の熊野古道のある東紀州地域への 観光アクセス向上への責献が期待され，平成25年度に全線開通予定である.このうち，新鹿トンネルは熊野新鹿IC の西側に位置し，環境省快水浴場100選に選定されている新鹿海水浴場に近接する．工事には平成22年4月に着手し ，工事用搬入路の施工時期が遅れたが，平成23年4月に掘削を開始，平成24年2月に貫通した.本稿では，トンネル 掘削，トンネル覆工などにおいて，さまざまな工夫を実施したので，その概要を報告する．%National Route 42 Kumano-Owase Road is a limited-access route of 18.6 km that links Owase city and Kumano city in Mie Prefecture and forms an expressway network as part of the Kisei Expressway. It is hoped that this will contribute to industrial development in the surrounding area and improving access for tourists to the Higashi-Kishu area which includes Kumano Kodo, the World Heritage Site and entire lines are expected to open in fiscal 2013. The Atashika Tunnel on this route is on the west side of Kumano Atashika Interchange and is adjacent to the Atashika swimming beach which has been selected as one of the top 100 bathing places by the Ministry of the Environment. Work was begun in April, 2010 and the construction schedule for the works service roads was delayed but excavation started in April, 2011 and penetration was achieved in February, 2012. This report gives an outline of the various innovations that were implemented in tunnel excavation and lining work.