Development of a leaf-vein-pattern fracture grouting method for soil liquefaction countermeasures

¹ Centre for Railway Earthquake Engineering, Railway Technical Research Institute, Tokyo, Japan
² R&D Centre, Raito Kogyo Co. LTD, Tsukuba, Japan
³ Structural Engineering Centre, East Japan Railway Company, Tokyo, Japan

^* Corresponding author: This email address is being protected from spambots. You need JavaScript enabled to view it.

Abstract

This study proposes a novel fracture‑grouting method that injects grout in a leaf‑vein pattern, enabling efficient densification of liquefiable ground with a relatively low grouting ratio of approximately 10% by volume. Large‑scale trial tests were conducted to verify the feasibility and effectiveness of the method. Grouting was performed in a soil pit using a dynamic injection technique, followed by in‑situ investigations including Piezo drive cone tests (PDC), seepage tests, PS logging, and other in‑situ tests. Shaking table tests were also conducted to evaluate liquefaction resistance under earthquake loading. The results confirmed successful formation of leaf‑vein pattern grouted bodies in loose saturated sand and demonstrated significant increases in soil properties. The improved ground exhibited liquefaction resistance comparable to ideally compacted dense sand. These findings indicate that the proposed method provides an economical and practical solution for mitigating liquefaction hazards in extensive sandy deposits, contributing to enhanced seismic resilience of infrastructure.