A Simplified Approach to Design Jet-Grouted Bottom Sealing Barriers for Deep Excavations in Deep Aquifers

This paper presents a simplified methodology for the design of jet-grouted bottom sealing barriers (temporary water-tightness structures) for deep excavations that was undertaken in deep aquifers. The bottom sealing barriers are usually required to prevent uplift failure against the water head below. Additionally, jet-grouted bottom sealing barriers are never perfect due to the uncertainties of jet grouting columns at the site, so the design must carefully consider the analysis of seepage. For these reasons, the proposed calculation procedure focuses on two different failure mechanisms (i.e., “instability failure” and “seepage failure”) of massive bottom sealing barriers. Subsequently, the design parameters of the jet-grouted bottom sealing barriers (e.g., depth and thickness) for an excavation case were determined while using the proposed design procedure. The field pumping test results show that the water-tightness performance of bottom-sealing barriers performed at site is good, which ensures that the water level inside the excavation can reach the desired level and the groundwater drawdown outside can be minimized. The leakage flow rate of bottom-sealing barriers is lower than the designed maximum allowable seepage when the water level inside stabilizes at the final period of the pumping test.

Abstract licence: CC BY

A person counts once a day per paper. We keep no cookie and no address: a reader is a hash that changes every day. Any month under five reads shows no number.