Investigating the soil consolidation via vacuum method by using numerical analysis

Document Type : Research Article

Authors

1 Department of Civil Engineering, Central Tehran Branch, Islamic Azad University, Tehran, Iran

2 Department of civil engineering, Central Tehran Branch, Islamic Azad University, Tehran, Iran

3 Department of Civil Engineering, Engineering Faculty, Islamic Azad University, Central Tehran Branch

Abstract

Due to increasing population and urbanization and lack of suitable land in terms of bearing capacity, construction is performed on soft soils, especially clays with low bearing capacity and excessive conventional settling characteristics. In these types of saturated soils, the construction of structures, such as large buildings, will release pore water pressure and therefore create a consolidation. One of the ways to reduce consolidation to the permissible amount specified in the regulations is to use a preload method that will require soil and embarkment operations and ultimately, necessity the removal of those embarkments. Vacuum combined with vertical drainage is an effective way to reduce the number of soil operations and associated costs, which in other words will accelerate the construction of structures and reduce costs. In this study, the effect of several parameters on the amount of consolidation was investigated by simulating soil consolidation via using the COMSOL Multiphysics and GeoStudio software. Based on the results, it was found that increasing vacuum intensity in vacuum chambers, increasing soil void ratio, and increasing bedrock depth, each of them accelerated the consolidation process. However, the number of vacuum terminals does not have a significant impact on this process.

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