Development of a High Early-Strength Anchor Mortar for Tunnel Construction

This article describes the development of a high early strength anchor mortar that is to be used in tunnel construction to secure the outer lining of the tunnel. Anchor mortars currently available on the market have a curing time of one to several days, while the anchor may not yet be loaded. Accelerating the curing process could significantly speed up the load-bearing capacity and improve the utilisation of the anchors. In this context, the early creation of a load bearing vault plays an important role, as it would allow to reduce the thickness of the outer lining. The construction progress could be accelerated by an anchor mortar with high early strength, thus contributing to cost savings.

1 Introduction

In tunnel construction, a reduced construction time leads to significant cost savings. Therefore, the demand for faster construction processes is high. Any curing time that exceeds the required working time is an economic and technical disadvantage. Also, due to construction constraints, anchoring may be scheduled for specific time windows (e.g. night shift). This procedure requires a high early-strength anchor mortar. Furthermore, in areas where it is necessary to ensure the full load-bearing capacity of the anchor within a short period of time (e.g. fault zones), so far...

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