Join us at DFI 44th Annual Conference on Deep Foundations in Chicago

October 11, 2019

The Deep Foundation Institute (DFI) 44th Annual Conference will held in Chicago, IL on October 15-18, 2019.

Ali Ghandeharioon, Ph.D, P.Eng., one of KCB’s geotechnical engineers, will be presenting a poster about the “Site Development and Foundation Planning for a Wastewater Treatment Plant Expansion”. The paper for this poster was co-authored with Steven R. Ahlfield, M.Sc., P.Eng., Principal Geotechnical Engineer at KCB's Power and Transportation Group.

The poster will be on display throughout the conference in the Exhibit Hall, Salons C & D, Lower Level, Hilton Chicago. Ali will be at the poster display on Wednesday, October 16, 2019, from 6:00 p.m. to 8:00 p.m. to network with conference attendees and answer questions.

Presentation Summary

A wastewater treatment plant, commissioned in 1978, is undergoing a major expansion. Planning various phases of the 80,000 m2 expansion at this site requires an understanding of the static and dynamic site response during and after construction, and the potential impact on adjacent properties and infrastructure. The expansion project requires nominally 5 m of site grading fill for flood protection. The site is underlain by loose to compact fine sand over firm to very stiff clay stratum that extends to great depths. The large areal extent of the site grading fill will cause stress changes to great depths and settlement in the compressible fine-grained soils. Ground improvement is required to mitigate the liquefaction hazard in the fine sand stratum, and preloading is proposed to reduce post-construction settlements in the deep clay. Analyses were carried out to assess the effects of past loading, proposed preload and surcharge heights, lateral extents and durations as well as vibro-replacement ground improvement on post-construction settlements. Two design options were considered for the preload footprint across the site and foundation system for proposed facilities. It is shown that limiting the preload extent and founding some of the proposed structures on deep friction piles reduce the predicted settlements of adjacent infrastructure and result in reasonable performance for the proposed facilities.

Full conference program: