| Of soils discharged from construction sites、 those that have insufficient strength or are otherwise unsuitable for use as foundation material have been disposed of until recently in Hokkaido. With the growing interest in effective recycling of such soils、 they are now being modified with solidifying agents and are often used as filling material. Construction projects have grown in scale、 and to create employment opportunities、 construction often extends well into the winter. [*]Recycled soils modified with solidifying agents are becoming used in cold weather、 bringing concerns over the effects of low temperature on the final strength of the material. Curing temperatures are known to affect strength when unsuitable soil is modified with cement or lime. The temperature is low during winter construction、 but it rises in spring、 and this change in air temperature could affect the strength of modified unsuitable soil. However、 few studies have examined the effect of temperature changes on the strength of modified soil. [*]This research obtained unconfined compressive strengths in modified soils that were cured under various temperatures and curing durations. The results have revealed that the strength varies according to the curing temperature; even with low initial curing temperatures、 the final strength is greater when subsequent curing temperatures are higher; and the strength does not increase with time under freezing conditions. |
