Notwithstanding the advance in tunnel constructions made by the rapid development in shield tunneling techniques, it is still difficult to precisely determine the structural response of the segmental lining due to uncertainties in the construction process and ground condition. This study presents a field measurement of the first underwater high-speed railway shield tunnel in China to gain a direct and deeper understanding of the structural response of segmental lining during and after the construction. The pre-installed sensors collected concrete strains of three measurement rings in soft ground, soil-rock layer, and rock stratum, respectively. The internal forces of segmental lining deriving from measured strains are analyzed and discussed according to the construction process. The results have shown that the field dataset captures the structural response characteristics from the assembling process to the stable stage. Construction activities, like the assembling process, jacks action, and deflection of shield attitude, etc., have a significant influence on the internal forces of segmental lining no matter during construction or in long-time. What’s more, the influence of the grout layer on structure response is investigated based on measured data by bedded-beam method. The results show that it is necessary to consider the impact of the grout layer on the subgrade modulus to get a reasonable estimation of the bending moment in the serviceability stage. The sensitivity of segmental ring internal forces to variations in grouting layer stiffness increases with increasing ground stiffness, whereas it gradually decreases as the stiffness of the grouting layer increases. This study provides a good engineering practice reference for slurry TBM tunnelling in mixed strata.
Wang et al. (Mon,) studied this question.