In projects that involve surcharge and prefabricated vertical drains (PVDs) systems for the treatment of weak underlying layers, embankment failures, tension cracks, and differential settlements, surficial heaves, and foundation failures were addressed in various literature. Overestimation and unrealistic design assumptions made by geotechnical and structural engineers are the main reasons for most of the cases. In all these cases a simple collaboration between different parties in the project ranging from designers to field engineers could have decreased or prevented these undesirable outcomes. The problem of neglecting the infiltration of the embankment in the ground as a new distinct layer with all the necessary requirements, and also disturbance caused as a result of PVDs installation in four cases: preloading case, fill removal, main structure construction, and post- construction phase are discussed. A few design recommendations are given regarding the stated issues. Since after the completion of soil treatment operations, the soil engineering parameters and in some cases even soil stratification had changed, care should be taken to use the new treated parameters in the final design process, not the preliminary site report parameters. Neglecting this issue may lead to severe malfunctions and even unpredictable failures. BIM technology has the possibility of integrating all aspects, and complexities of geotechnical engineering in the structural-architectural platform as a whole, which would revolutionize the construction industry. Till now only the structural-architectural part is done and further research and investment are necessary for the geotechnical aspect. Manuscript profile

One of the most challenging parts of every project including prefabricated vertical drains (PVDs) with surcharge preloading for ground improvement in construction period is lateral displacements that occur in toe of embankment. In this paper Finite element Geostudio 2018 was used for modeling and verification of the full-scale test embankment which were constructed to study the effectiveness of PVDs combined with surcharge preloading at Bangkok airport. The surcharge preloading was modeled by staged construction using a coupled analysis which gives best results for primary consolidation cases. Different depths were modeled and the results were compared and analyzed. It was shown that by increasing the installation depth of PVDs the lateral displacement increased underneath but lateral displacement at ground surface remain approximately constant. In the case of decreasing PVDs length the lateral displacement remains constant for ground surface and decrease slightly with respect to verified model. Although it should be mentioned that like any geotechnical big scale project because of distinct soil characteristic of clay soils and layers properties of any project, complete investigation and modeling is essential prior to finalizing the ultimate design by competence geotechnical consultants. Manuscript profile