Posiva publishes Working Reports and Posiva Reports. From the year 2006 nearly all the reports have been published on our webpage and they can be found in the databank. In the databank you can also find our Annual Reviews and some other publications as well. You can also find print-quality pictures and useful links in the databank.

Recent publications

Workreport 2016-53



Initial Buffer and Backfill Wetting: Pellet-Filling Component


Martikainen, J., Schatz, T.



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Three series of laboratory tests (called pellet box tests) were performed at different configurations to investigate the effects of initial groundwater inflow into a deposition hole or tunnel using current Posiva buffer and backfill pellet-filling designs. Series 1 tests were carried out using a 1 m × 1 m × 50 mm (length × height × width) effective pellet box size, series 2 tests were carried out using a 2 m × 1 m × 50 mm effective pellet box size and series 3 tests were carried out using a 2 m × 1 m × 250 mm effective pellet box size. Series 1 and 2 tests were concerned with buffer pellet-filling design (50 mm gap) and series 3 tests with backfill pellet-filling design (250 mm gap).

 Inflows of interest were introduced into the pellet-filled volumes and the distribution of the inflowing water, resistance to inflow and heaving (uplift) response were assessed. As these tests were simulating the initial saturation behaviour in deposition holes and tunnels, they were conducted under open conditions to approximate 1) deposition holes prior to the placement of overlying backfill and 2) deposition tunnels during backfill installation. The distribution of infiltrating water and subsequent heaving response of the pellet-filled volumes were mainly dependent on inflow rate and design (buffer or backfill type).


Water infiltration, initial state, wetting behaviour, heaving, buffer, backfill, pellet-filling, MX-80, Cebogel QSE


WR 2016-53_web (pdf) (15.4 MB)


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