Vertical drains can be employed in reduced permeability soils (clays, silts) and will noticeably improve the charge of consolidation. Prefabricated vertical drains include a flexible plastic core (flat or cylindrical in form) wrapped in a very spun-bond filter fabric and can be installed to depths of greater than fifty m. https://truevalueoflife87776.thelateblog.com/33677250/facts-about-top-engineering-companies-in-bd-revealed