Analysis of a Prefabricated Vertical Drain (PVD) Soil Improvement Project

Authors : Ahmet Can MERT, Akın ÖNALP, Ersin AREL

Pages : 11521-11541

Doi:10.18400/tekderg.641218

View : 8 | Download : 2

Publication Date : 2022-01-01

Article Type : Research Paper

Abstract :A settlement analysis has been carried out for several sectors of a rail station yard improved with prefabricated vertical drains insert ignore into journalissuearticles values(PVD); in Istanbul, Turkey, that exhibited prolonged consolidation beyond the predicted values in certain sectors of the treated zone. Final settlement and End of Primary insert ignore into journalissuearticles values(EOP); settlement times have been estimated theoretically as well as using the Asaoka graphical procedure. The compliance of settlement-time curves with in-situ measurements and Asaoka solution has been investigated. A geotechnical model was developed for finite element and three-dimensional consolidation analyses. The settlement curves obtained by varying horizontal-vertical permeability coefficient ratio insert ignore into journalissuearticles values( k h / k v ); and in-situ measurements have been compared, and  k h / k v  values corresponding to 90% degree of consolidation has been computed for all sectors. The effect of drain spacing insert ignore into journalissuearticles values( s drain ); as well as drain length insert ignore into journalissuearticles values( L drain ); on the rate of consolidation have been examined for each sector, keeping the specified ratios constant. The times corresponding to 95% degree of consolidation insert ignore into journalissuearticles values( t 95 ); have been calculated using the theoretical solution and compared to in-situ measurements. Calculated  t 95 ‘s have also been compared to their estimated values   by varying the spacing insert ignore into journalissuearticles values( s drain ); and the length  insert ignore into journalissuearticles values(L drain );. Additionally, the required intervals of  s drain  and  L drain  have been obtained corresponding to the calculated  t 95  times.
Keywords : Prefabricated Vertical Drain PVD, Radial consolidation, 3D consolidation, Acceleration of consolidation, Consolidation settlement, Coefficient of permeability, Degree of consolidation, Consolidation rate, Asaoka pr