線路下の道路函体71mをHEP&JES工法で施工: 名古屋都市計画道路椿町線

摘要

JR東海は,名古屋市の都市計画道路椿町線が鉄道と交差する箇所に,アンダーパス工事をHEP&JES工法で施工している.そのうち,本施工区間では施工延長が約71mと長大掘進長を有しており,矩形断面ではJR東海で過去最長の掘進長である.本稿では当アンダーパスの構造概要を紹介したうえで,HEP&JES施工時の技術開発,計画時における課題•対策,および実施工時の課題克服策として実施した「想定外支障物への対策」「掘進中の出水に対する対策」「JR東海で初となる鉄道下の土留めの盛替え工法」について詳細を報告する.%JR Tokai is currently constructing an underpass of the Tsubakicho Road as a Nagoya City Planning Road where it passes under JR railways using the HEP & JES method. JR Tokai is in charge of about 71m stretch to excavate and build it. It is the company's longest rectangular cross-section excavation on record. This report contains an outline of the underpass construction as well as details of technological developments during use of HEP & JES technique, problems and measures during planning, and various measures against problems faced during construction: a measure against unexpected obstacles, dewatering during excavation and JR Tokai's first use of earth retaining replacement method under railway tracks.