In an open letter to geotechnical engineers and agencies that specify geosynthetics on their projects, the Geosynthetics Manufacturers Association (GMA) has requested that specifiers use the correct standards when referring material properties of geotextiles and other geosynthetics. For example, they refer to two standards that are now out of date, The Mullen Burst Strength and the Puncture Test which were both originally designed for paper. The correct standard is the Static (CBR) Puncture ASTM D6241. See the entire letter on Geosyntheticsmagazine.com. (Photo of Geotextiles from Nilex.com)
Sample Guide Specifications for Construction of Geosynthetic Reinforced Soil-Integrated Bridge System (GRS-IBS)
This guide was issued to provide guidelines for construction of the geosynthetic reinforced soilintegrated bridge system (GRS-IBS). Refer to Geosynthetic Reinforced Soil Integrated Bridge System Interim Implementation Guide for GRS-IBS design and construction guidelines. This […]
Univ. of Missouri’s Historic Memorial Union, Built to Honor WWI Dead, Gets New Life with TerraThane Geotechnical Foam
MOUNT AIRY, NC—The Univ. of Missouri’s iconic Memorial Union, with its Gothic architecture and central bell tower, was built to commemorate the 117 Mizzou alumni who lost their lives in WWI, and has been under silent attack. Like all buildings built atop the ancient dry riverbeds of the tributary valleys of the Missouri River, the soil beneath is a mixture of sand, clay, and fine rock particles and highly susceptible to erosion from water. So, while hundreds of thousands of students walked the hallways of the building, water escaping steam pipes far beneath caused severe drying of the soil and destabilized it enough so that erosion created voids, or cavities in the soil, some as large as four feet. In turn, this caused the concrete slab floors atop the voids to become uneven, and the eventual danger of even greater problems loomed large.
A team of engineers went after the problem, including MU alums, Matt VanderTuig, P.E., of Bartlett & West, Jefferson City, MO, and Mark Whitehead, P.E. with extensive structural design and environmental engineering management experience. They suggested to Chris Hentges, president of SIRCAL Contracting, Jefferson City, the general contractor in charge of the job, that instead of using the older method of mudjacking, a highly involved and intrusive process of drilling large holes in the slabs—sometimes removing the slabs entirely—and pumping “mud”, ultra-heavy Portland cement-based grout, into the void, then leveling the slabs, that the university might better be served by using the newer polyurethane foam system method called “foamjacking” or “polyjacking.”
[Editor] Be sure to click through for the rest of the interesting project from GeoPrac sponsor NCFI Polyurethanes and TerraThane! [/Editor]
Most geotechs are familiar with the Journal of Geotechnical and Geoenvironmental Engineering (JGGE), one of the (if not the) premier journal in the industry. It’s published by the ASCE’s Geo-Institute (G-I) and accounts for about 20% of the revenue of the G-I organization.
The G-I’s President, Dr. Jean-Louis Briaud, convened a task force in early 2009 to investigate if the JGGE is “adequately serving as a venue for practice oriented papers.” According to the final report from the Proposed "Journal of Geotechnical Engineering Practice" Task Force, the reason for the task force is that: