Construction of a new building founded on a clayey soil was completed in January $2010 .$ In January $2014,$ the average consolidation settlement of the foundation in clay was recorded as $10 \mathrm{~mm} .$ The ultimate consolidation settlement was estimated in design as $40 \mathrm{~mm}$. Considering double drainage to occur at the clayey soil site, the expected consolidation settlement in January 2019 (in $m m,$ round off to the nearest integer $)$ will be
Construction of a new building founded on a clayey soil was completed in January $2010 .$ In January $2014,$ the average consolidation settlement of the foundation in clay was recorded as $10 \mathrm{~mm} .$ The ultimate consolidation settlement was estimated in design as $40 \mathrm{~mm}$. Considering double drainage to occur at the clayey soil site, the expected consolidation settlement in January 2019 (in $m m,$ round off to the nearest integer $)$ will be