Posts Categorized: GEOWEB Geocells for Unpaved Roads & Pavement Reinforcement

Build a Stronger Foundation for Infrastructure Projects with 3D Soil Confinement

It’s no secret that America’s infrastructure is desperately in need of investment. The American Society of Civil Engineers (ASCE) gave the country’s infrastructure an overall grade of D-plus in its 2017 Infrastructure Report Card—dangerously close to an outright failing grade. The ASCE estimates that the U.S. will need to spend nearly $4.5 trillion by 2025 to fix the country’s roads, bridges, dams, and other infrastructure. Our nation’s roads and bridges—commonly referred to as the “backbone” of the U.S. transportation system—received grades of D and C-plus, respectively. These transportation systems are deteriorating due to advancing age, increasing use, and inadequate funding. This degradation leads to a significant cost to users in terms of time, money, and safety. There are over 4 million miles of road in the United States, and the cost to maintain these roadways can vary greatly by state. Several factors determine maintenance costs, including the type of pavement surface, its current condition, its geographical location, average precipitation, number of annual freeze/thaw cycles, and frequency of use. Three-Dimensional Geocells Provide Solutions to Aging Infrastructure The long-term performance of infrastructure construction projects depends on the strength of the underlying soil. Through an interconnected honeycomb-like network, 3D geocells confine and stabilize… Read more »

Why Geocells Outperform Geogrids for Road Construction

Written By: Bill Handlos, PE, Director of Presto Geosystems Geocells (cellular confinement) offer a more effective and practical 3D design solution to load support challenges than multilayered 2D geogrid efforts. Geocells transfer applied loads instantaneously, delivering practical soil stabilization in a product that is fast and easy to install.        How do geogrids work? Geogrids rely on rutting, displacement and lateral movement of the road material to activate the load support reaction of the product. As shown below, failure of the driving surface must occur before the geogrid reacts. As a result, rutting and soil displacement is a prerequisite reality to the system. Since the geogrid is two-dimensional, material not located directly within the plane occupied by the geogrid is free to move, shift and displace. It is essential that geogrids are placed in a flat or a pre-tensioned manner—but that is not practical in a construction environment. It is common to see geogrids unrolled over a prepared grade with an undulating surface. As aggregate is placed over the top of the geogrid, the material kinks and waves, further warping the 2D plane. The geogrid is rarely pulled tight during installation which does not allow full tension under… Read more »

Highway Stormwater Control: Porous Vegetated Road Shoulders

Written by William G. Handlos, P.E. Highway Stormwater Control: Porous Vegetated Drivable Road Shoulders Gravel road shoulders are not porous. Rainwater sheet flowing off highway pavement passes right across the aggregate shoulder carrying with it sediment and other pollutants that ultimately end up in freshwater creeks and rivers. Aside from pollutant loading, re-grading shoulders is a continuous activity for State and County crews to repair eroded sections after several rain events. Some counties have taken a smart solution approach to this problem and are using geocell cellular confinement systems to reduce maintenance costs and to improve water quality.  Shown below are the cross sections detailing a GEOWEB® geocellular drivable vegetated shoulder solution. The infill to the geocell is made up of 2/3rd clear stone aggregate (void ratio 30 – 40%) and 1/3rd topsoil. The topsoil remains uncompressed within the interstitial spaces between the stone, and the stone is the structural component that carries the load. The topsoil allows for the vegetation roots to grow and feed upon the nutrients and water in the topsoil.  This system percolates runoff from the highway while offering proper load support for vehicles that pull off the side of the road. The GEOWEB® cells confine the… Read more »