Internal Strain Evolution Test of Cemented Backfill Based on OFDR Technology

doi:10.12068/j.issn.1005-3026.2023.02.014

Abstract

Abstract: By using optical frequency domain reflectometer(OFDR)， a high-precision laboratory test of backfill was carried out， and the internal strain evolution law and distribution characteristics of the backfill during the early hardening process with different cement content was obtained. The results show that the internal strain evolution of the backfill is affected by the combined action of the physical sedimentation of solid particles and the chemical hydration reaction， which can be divided into four stages: physical sedimentation and stretching， hydration exothermic expansion， chemical autogenous shrinkage and basically stablestage. The internal strain distribution of the backfill mainly presents an upward convex curve in the early stage， and with the increase of curing time， it presents a multi-peak curve characteristic; OFDR technology can be used to realize high-precision distributed measurement of the internal strain of backfill and analyze the evolution characteristics of internal strain of backfill.

Key words: OFDR distributed monitoring; strain evolution; cemented backfill; spatial and temporal distribution; chemical shrinkage

CLC Number:

TD853

LI Lei， HOU Chen， ZHU Wan-cheng， YANG Liu-jun. Internal Strain Evolution Test of Cemented Backfill Based on OFDR Technology[J]. Journal of Northeastern University(Natural Science), 2023, 44(2): 258-264.

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