Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
Experimental and analytical study of shield tunnel face in dense sand strata considering different longitudinal inclination
Highlights A new 1-g experimental equipment in evaluating tunnel face stability was designed. Tunnel face failure mode induced by longitudinal inclination angle was investigated. A series of novel theoretical models were proposed.
Abstract Predicting the face support pressure and understanding the failure mode for shield tunnel with different longitudinal inclination, δ, in dense sand strata are crucial. Six laboratory model tests are conducted to explore the failure mechanism of tunnel face with δ = 15°, 0°, and −15°. It shows that the face support pressure declines sharply to the elastic limit value, and further decrease slowly to the minimum value for all δ conditions. When δ = 15° or 0°, the face support pressure rebounds slightly to a residual value. However, rebound is not prominent for δ = −15°. The influence of “soil arch” strength reduces when δ varies from −15°, 0°, to 15°. The final shape of the failure zone shows a “chimney” pattern, in which the area of the failure zone increases with δ. Similar failure patterns are obtained from the numerical simulations. Based on the measured contours of failure zones, novel theoretical models are proposed to calculate the limit face support pressure for three inclination conditions. The face support pressure, pu, is predicted to be the highest for δ > 0°, following by the cases of δ = 0° and δ < 0°, and the change in pu is higher between δ > 0° and δ = 0°.
Experimental and analytical study of shield tunnel face in dense sand strata considering different longitudinal inclination
Highlights A new 1-g experimental equipment in evaluating tunnel face stability was designed. Tunnel face failure mode induced by longitudinal inclination angle was investigated. A series of novel theoretical models were proposed.
Abstract Predicting the face support pressure and understanding the failure mode for shield tunnel with different longitudinal inclination, δ, in dense sand strata are crucial. Six laboratory model tests are conducted to explore the failure mechanism of tunnel face with δ = 15°, 0°, and −15°. It shows that the face support pressure declines sharply to the elastic limit value, and further decrease slowly to the minimum value for all δ conditions. When δ = 15° or 0°, the face support pressure rebounds slightly to a residual value. However, rebound is not prominent for δ = −15°. The influence of “soil arch” strength reduces when δ varies from −15°, 0°, to 15°. The final shape of the failure zone shows a “chimney” pattern, in which the area of the failure zone increases with δ. Similar failure patterns are obtained from the numerical simulations. Based on the measured contours of failure zones, novel theoretical models are proposed to calculate the limit face support pressure for three inclination conditions. The face support pressure, pu, is predicted to be the highest for δ > 0°, following by the cases of δ = 0° and δ < 0°, and the change in pu is higher between δ > 0° and δ = 0°.
Experimental and analytical study of shield tunnel face in dense sand strata considering different longitudinal inclination
Cheng, Cheng (Autor:in) / Jia, Pengjiao (Autor:in) / Zhao, Wen (Autor:in) / Ni, Pengpeng (Autor:in) / Bai, Qian (Autor:in) / Wang, Zijun (Autor:in) / Lu, Bo (Autor:in)
02.04.2021
Aufsatz (Zeitschrift)
Elektronische Ressource
Englisch