Year: 2025
Type: article
Abstract: This paper analyzes the combined effects of grout properties (mix ratio, viscosity), construction speed, grouting pressure, bolt preload, and tunnel slope on shield tunnel uplift induced by synchronous grouting. A finite-difference model incorporating 12 consecutive segments was developed, incorporating time-dependent grout parameters (static buoyancy, viscosity) fitted via exponential functions. Field tests conducted on Ningbo Rail Transit Line 8, along with 3D-printed segment experiments, confirmed model reliability. Results show that grout with a shorter initial setting time minimizes uplift, while faster construction speeds increase the magnitude of uplift. Higher bolt preload reduces uplift by enhancing joint stiffness, whereas grouting pressure has a negligible influence. The uphill tunnel slope exacerbates uplift while the downhill slope mitigates it, providing practical guidelines for slope-specific construction protocols.
Source: Scientific Reports
Institution: Ningbo University
Language: English
Subfield: Civil and Structural Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,690
Award: G5957954141
OpenAlex ID: W4416226322