「T-e Con^®地盤改良材」を用いた改良地盤の品質調査

技術センター木造人道橋への適用

大塚 修平^＊１・渡邊 徹^＊１・濱 健太郎^＊１・松井 秀岳^＊２・池上 浩樹^＊２・一色 裕二^＊３・岩田 曉洋^＊４

当社はカーボンニュートラル社会実現に貢献するため，CO₂排出量を大幅に削減できる地盤固化改良材「T-e Con/地盤改良材」を開発し，大成建設技術センター木造人道橋の地盤改良工事に初めて適用した。本地盤固化改良材は，高炉スラグの使用比率を高めつつ，セメントを使用しないことでCO₂排出量を抑制できるものである。本地盤改良工事におけるCO₂削減量は，従来比で1,733 kg（48 %減）と算出され，その効果が大きいことが確認された。また，本地盤改良材による地盤改良工事の施工性が従来と同様であること，特別な装置を必要としないこと，施工後の改良地盤から採取したコア供試体の圧縮強度が目標値を大きく上回ること，圧縮強度のばらつきが従来の固化材を用いた場合と同等であることなどを確認した

キーワード：T-e Concrete，地盤改良，現場施工，浅層混合処理工法，一軸圧縮強さ

＊１ 技術センター 都市基盤技術研究部 構造研究室
＊２ 技術センター 社会基盤技術研究部 地盤研究室
＊３ 設計本部 構造設計第ニ部
＊４ 建築本部 技術部

Quality Investigation of Improved Ground applying "T-e Con^®" Ground-Improvement-binder

Applying to Timber Pedestrian Bridge in Taisei Advanced Center of Technology

Shuhei OTSUKA^*1, Toru WATANABE^*1, Kentaro HAMA^*1, Hidetake MATSUI^*2, Hiroki IKEGAMI^*2, Yuji ISSHIKI^*3 and Akihiro IWATA^*4

In order to contribute to the realization of a carbon-neutral society, we have developed a ground improvement binder, "T-e Con/Ground Improvement Binder". The new binder, which can significantly reduce CO₂ emissions, was first applied to the ground improvement work of a timber pedestrian bridge at the Taisei Advanced Center of Technology. By increasing the usage ratio of blast furnace slag and eliminating cement, the binder effectively reduces CO₂ emissions. The CO₂ reduction achieved in the ground improvement work was substantial, with an estimated 1,733 kg (a 48% reduction) compared to conventional binder. Furthermore, it was confirmed that the efficiency of ground improvement work using this binder is equivalent to that of conventional methods, with no special equipment required. The compressive strength of the core sampling specimens obtained from the improved ground exceeds the target value, and the variation in compressive strength is consistent with that observed when using conventional binder.

Keywords: T-e Concrete, ground improvement, field execution, shallow mixing method, unconfined compression strength

*1 Structure Research Section, Urban Engineering Research Department, Taisei Advanced Center of Technology
*2 Geotechnical Research Section, Infrastructure Technology Research Department, Taisei Advanced Center of Technology
*3 Structural Engineering Department II, Design Division
*4 Technology Control Department, Building Construction Division

13 - TAISEI ADVANCED CENTER OF TECHNOLOGY TECHNICAL REPORT No.57 2024