Surface Settlement Time Lag Induced by Shield Tunneling in Urban Sandy-Pebble Stratum

Abstract:

This paper focuses on the surface settlement time lag caused by shield tunneling in sandy-pebble stratum in Chengdu. A surface collapse case during Chengdu metro construction was introduced and the mechanism of surface settlement time lag was analyzed. The process of the ground settlement was simulated using the UDEC software. It is found that: 1) over-excavation and the grouting failure are the root causes of surface settlement; 2) characteristics of the sandy-pebble stratum in Chengdu induce ground voids behind tunnel segmental lining; 3) the mechanism of surface settlement time lag can be explained by temporary ground arch in the sandy-pebble stratum.

• Periodical: Applied Mechanics and Materials (Volumes 405-408)
• Pages: 1326-1329
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.405-408.1326
• Online since: September 2013
• Authors: Shuai Man
• Keywords: Sandy-Pebble Stratum, Shield Tunnel, Surface Settlement, UDEC Software

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