Extensive damage of sewage pipes was caused by past large earthquakes such as the 2004 Niigataken-Chuetsu earthquake. Typically, their uplift was induced by liquefaction of backfill soils, and several measures have been taken against it. Since the solidification method as one of the countermeasures still needs to be studied from a view point of the long term mobilization of sufficient strength, a series of unconfined compression tests was conducted on a lime-treated waste soil. Under the test conditions employed for the current study, strength reduction was observed at the initial stage of curing under water, which was followed by rather a stable strength mobilization up to 1 year of curing. [This abstract is not included in the PDF]