ANALYSIS ON THE STABILITY OF THE TEMPORARY SUPPORT FRAME OF THE TUNNEL EXCAVATED IN REINFORCED SAND MEDIUM

Abstract

This paper presents the effect of sand reinforcement by pumping water into the sand around the support frame to evaluate the stability of the support frame system. The sand was collected in the Central region in Vietnam and experimented in the laboratory with different water content and void ratio. The most suitable water content for the reinforcement to achieve high efficiency is W = 15% from the experimental results. Conduct numerical tests to evaluate the working of the temporary support system before and after the sand is reinforced as well as to evaluate the effectiveness of the reinforced sand layer thickness. The research results have practical implications for the construction of tunnels in the sand.