Monday, February 6 | 9:45 – 11:45 am
Workshops are two hour in-depth sessions offering 2 PDH. Workshops are available at no cost to all full registrants and registrants with a One Day – Monday registration.
Geosynthetic Reinforced Embankments on Soft Foundations
Bob Holtz, PhD, PE, D.GE, Dist. M. ASCE, University of Washington
The design and construction of embankments on very soft foundations is one of most challenging geotechnical problems. Without some type of foundation soil improvement, failures are common especially on very soft sites. Soil reinforcement with geosynthetics is often the only economical solution, and some projects could not be constructed without geosynthetics. The lecture begins with a brief overview of conventional treatments for soft ground construction. Early case histories, mostly failures, are described that provided valuable lessons and concepts that we use today for design and construction. Analysis and design procedures are then outlined, along with the selection of the required properties for the geosynthetics and embankment soils. Sample specifications, cost considerations, as well as inspection and instrumentation are also described. Because proper construction is so critically important for success of these projects, a detailed discussion of construction procedures completes the course. Detailed lecture notes and copies of the course slides will be available.
Geosynthetic Stabilization of Granular Layers in Paved Roads
Erol Tutumluer, PhD, University of Illinois at Urbana-Champaign, Jorge Zornberg, PhD, PE, The University of Texas at Austin
Geosynthetic stabilization is often associated with a paved road when an aggregate base/subbase is constructed over a subgrade having CBR ranging from 3 to 8 (FHWA, 2008). The main benefits of unbound aggregate layer stabilization include (1) decreasing time-dependent rutting by providing an increased modulus of unbound aggregates at the time of construction and added confinement from compaction-induced geosynthetic tension and (2) minimizing degradation of the modulus of unbound aggregates over time by proper control of lateral displacements in unbound aggregates and maintaining initial confinement of unbound aggregates. The identified mechanism is the development of lateral restraint through tension and shear transfer to minimize the lateral displacement of unbound aggregates. Both friction and interlocking between aggregates and geosynthetics contribute to the base stabilization. Modern design procedures are needed for establishing more common use of geosynthetics for base stabilization within the framework of a mechanistic-empirical pavement design approach. This workshop is intended to present, review an discuss the latest developments in the quantification of aggregate layer stiffness characteristics of the geosynthetic-aggregate geocomposite, aka, the mechanically stabilized layer. Through presentations and discussion, a path to development of modern design procedures will be presented.
Learn The Concept of The Dewatering Tube System Through Experience
Ike Chen and Zoe Lin, ACE Geosynthetics, Marco A. Sánchez, Commercial Director, ML Ingenieria; Seva Iwinski Bray and Eddie Snell, Applied Polymer Systems; Carlos Moreno, Pavco Wavin Geosynthetics (Columbia)
Geotextile tube is proven to be a cost-effective solution for some hydraulic and civil engineering applications. In addition to this, geotextile tube is also recognized as a good approach for some dewatering needs. And there are many factors that can affect the dewatering performance of a geotextile tube; besides the characteristics of slurry, the selection of geotextile, and the selection of polymer and its dosing ratio are also key factors. This workshop will focus on understanding how the selection of geotextile and polymer’s dosing ratio affect the dewatering performance of geotextile tube by practical experiment.This is a hands-on dewatering workshop.
30 Years of Lessons Learned on Geomembrane Installation Quality
Glen W Toepfer, CQA Solutions, Ltd.
Geomembranes are a vital and primary barrier to prevent of environmental contamination. Given the critical role of geosynthetics in environmental containment systems, correctly executing field construction is imperative to successful projects. So where do you go to learn correct construction processes, quality control, quality assurance and common pitfalls? The answer for most is you don’t. As a word of mouth trade there has been a significant lack of formalization of field processes.
This workshop is here to share lessons learned from over 30-years of field CQA throughout the United States. We will share lessons learned from all project phases – from conception through operations, as each phase is critical to long-term performance of the geomembrane barrier. Issues that should have been caught are often missed or overlooked, leading to potential catastrophic long-term impacts on the ability of a geomembrane to meet its designed/required containment objectives. Lack of knowledge is a key reason things get missed during construction.
Attendees will examine physical samples from the field, view numerous photographs and/or video while given a detailed discussion of key visual indicators, consequences, preventative measures, and proper resolution of issues. Discussions will also include proven best practices that are often overlooked or not used.
Topics will include: tips for identifying potentially suspect/inferior materials before shipment to site; discussion of common and not so common pitfalls in geomembrane containment system installations which compromise quality objectives; and the often-misunderstood limitations of new/developing technologies.
Two hours may not make you an expert of Geosynthetics but it can revolutionize how your field construction is executed to ensure better projects and a better environment.