The paper describes the performance of an extensively instrumented trial field of vacuum assisted fill loading with prefabricated vertical drains in the area of Texcoco Lake (2228 m a.s.l.) for the construction of the new International Airport of Mexico City. A vacuum preloading of approximately 60 kPa was applied on top of drains over a period of 180 days using the drain to drain technique combined with cylindrical capped drains (Star Drains) installed at 1.2 m interval on a triangular grid. The loading fill consisted of 2 m thick locally available low density volcanic material ("Tezontle"). Soil profile in the area is characterized by very soft Mexico City clay having notoriously very poor geotechnical properties. A final settlement close to 2 m was recorded at the central point of the fill corresponding to a consolidation degree of approximately 70%. Settlements measured both on the ground surface and at depth were in good agreement with predictions by numerical analyses.
Subjects: None provided
Author: Vito Nicola Ghionna, Prof., Luiz Guilherme de Mello, Prof., Valeriano Pastore, Managing Director, Roberto Andrighetto and Luca Pereira Cammarota
Publisher: DFI, EFFC