LIQUEFACTION COUNTERMEASURE STRUCTURE FOR GROUND

摘要

PROBLEM TO BE SOLVED: To provide a liquefaction countermeasure structure that is relatively inexpensive and easy to construct and prevents coseismic uneven settlement while maintaining the function of a ground when an excess pore water pressure is higher.SOLUTION: In a liquefaction countermeasure structure 20 for a liquefaction ground 10, an improved ground layer 21 is formed above a liquefaction layer 13 all over a parking area 7, and a horizontal drain layer 22 is formed above the improved ground layer 21 all over the parking area 7. In the parking area 7, a plurality of vertical drains 24 dispersively arranged and connected to the horizontal drain layer 22 are formed in the approximately vertical direction to reach the liquefaction layer 13, and drainage ditches 25 are provided. Excess pore water generated by the liquefaction of the liquefaction layer 13 is carried via the vertical drains 24 and the horizontal drain layer 22 into the drainage ditches 25 to prevent uneven settlement.