Abstract:

Wucunshan Tunnel of Xiamen which is designed as shallow large span structure needs to go through dense buildings in Punan territory, and construction difficulties is unusual both at home and abroad. By in-situ building lifting test and monitoring, two levels of building lifting by grouting can be seen: the first level is controlling and cutting building subsidence, the second is named building lifting strictly. The in-situ lifting tests show that the first level can be achieved with dynamic tracking and retrieving grouting successfully, whereas the second level requires much more refined grouting techniques. On one hand, the fulfilling of building lifting must be on the premise of the first level of retrieving grouting, finishing wall for grouting, and enforcing foundation soil. On the other hand, it depends on adequate grouting technologies, grouting amount, pressure, arrangement of grouting holes, holes and depths, etc. Related monitoring results make clear that land lifting is standing out, and building subsidence is distinctly slowed down, however, building lifting is only light and fluctuant, and finally trend to subside. And they also show that there is great difference between land and building liftings, only large range, stable, uniform, undissipated land lifting can make safe and effective building lifting, By analytical and numerical methods, lifting grouting parameters will be optimized and gained, and building lifting deformation can be predicted, which can generally meet the engineering needs.

Key words: building lifting by grouting, shallow large span, going through buildings, monitoring, numerical modeling