Reviving the Palos Verdes Reservoir

October 1, 2016

Introduction California is home to one of the most active water resource infrastructure sectors. Geosynthetics can play an enormous role with the creation and rehabilitation of these water resources. The 76-year-old Palos Verdes Reservoir in Los Angeles County provides an exemplary case (Photo A). The 360-million-gallon cell is currently undergoing an update that will greatly …

Members Only  

Wetlands restoration at San Pablo Bay

August 1, 2016

How geofoam, as lightweight structural fill, solved a variety of construction challenges on a roadway embankment project in support of wetlands restoration in Northern California Introduction As those in the design and construction community know well, every project is slightly different from the last regardless of how many times similar challenges have been faced. When …

Members Only  

Accelerated geosynthetic closure of a mine refuse site

Case history: Cambria Site 93 in Pennsylvania Introduction During the coal mining process—underground or surface—other unwanted soil and rock materials are mined along with the coal. A separation technology is used to best segregate the coal from the “refuse material.” After separation, various amounts of coal still exist in the refuse piles of material left …

Members Only  

State-of-the-art fuel storage facility at Point Loma

Refueling the life span: Effective secondary containment system Introduction In 2008, an eight-year military construction project was approved to replace the aging Point Loma Navy fuel storage facility that had been intermittently constructed between 1917 and 1954. Located at Defense Fuel Support Point (DFSP) Point Loma, San Diego, this was the largest construction project ever …

Members Only  

Questions and answers from the GMA Techline

Geosynthetic filter failure Q: I am interested in your upcoming webinar on geosynthetic filters and was hoping to get a little clarification on the content. I’m most interested in how geotextile fabrics are used with riprap but I also understand these fabrics are perhaps more commonly associated with roadway construction. How much does this webinar …

Members Only  

Recycled materials reinforcement?

June 1, 2016

Questions and answers from the GMA Techline We are soliciting information on the use of recycled materials in the reinforced zone of MSE walls. I recall you as the keeper of many case histories. Do you have any success or failure stories about such recycled content in a reinforced zone? I’m mindful of chemical attack …

Members Only  

Weld or sew?

Questions and answers from the GMA Techline We have a liner contractor who would like to wedge-weld geotextile rather than sew it. The material is simply a cushion layer below the 40-mil geomembrane and the contractor is concerned the sewn seams will affect wedge welding of the above geomembrane. Do you have a recommendation on …

Members Only  

Geosynthetics: The science that makes green roofs work

Green roofs 101­–From bottom to top Introduction Most green roofs use a variety of geosynthetic materials to support healthy and sustainable installations. Geosynthetics contribute in many ways to the operational success and long-term sustainability of green roof systems. Because they are lightweight, they reduce green roofs’ structural loading on buildings and also reduce the energy …

Members Only  

Strength test?

Questions and answers from the GMA Techline Something that has always puzzled me while performing the CQA for liners is the strength test for a weld using the extrusion gun. I always thought that if the weld does not pass for elongation, that has more to do with the sheet than how well the weld …

Members Only  

Environmental applications of geosynthetics in pipeline installations

Geo + Pipeline 101 Geosynthetics often play an important role on the environmental side of pipeline installations. During construction, actions must be taken to protect water quality, stabilize soil, and prevent soil erosion. Pipeline right-of-ways traverse many different types of landscapes, passing through sensitive resource areas such as streams and wetlands. Geosynthetics are used in …