Lin C.,University of Alaska Fairbanks |
Presler W.,University of Cincinnati |
Zhang X.,University of Cincinnati |
Jones D.,TenCate Geosynthetics |
Odgers B.,TenCate Geosynthetics
Journal of Performance of Constructed Facilities | Year: 2017
Beaver Slide is near 177.8 km (110.5 mi) on the Dalton Highway and the road gradient is approximately 11%, built on a hill side. Each year, soft spots, also commonly named as frost boils, were observed starting from late April and lasting for the entire summer. The frost boils have resulted in an extremely unsafe driving condition and frequent accident occurrences. Conventional repair methods cannot effectively solve this issue. A newly developed geotextile, which has high specific surface area, was installed in the selected test section to mitigate the frost-boil issue in August 2010. This type of geotextile can provide high wettability and relatively high suction (capillary force), consequently be able to laterally transport water (a high-directional transmissivity) under unsaturated conditions. Test results over the initial 2 years had proved the effectiveness of the geotextile to alleviate frost heave and the subsequent thaw-weakening issue. However, there were still some concerns regarding its long-term performance, such as clogging of the microscopic drainage channels and mechanical failures. The data collected during the past 5 years were used to analyze and evaluate the effectiveness of the wicking fabric. A scanning electron microscope was used to explore the interaction between the wicking fabric and in situ soils, and to determine the condition of the fabric 5 years after the installation. © 2016 American Society of Civil Engineers.
Perkins S.W.,Montana State University |
Christopher B.R.,Christopher Consultants |
Lacina B.A.,TenCate Geosynthetics |
Klompmaker J.,BBG Bauberatung Geokunststoffe GmbH and Co.KG
International Journal of Geomechanics | Year: 2012
Mechanistic-empirical modeling and design solutions have been routinely used for conventional flexible pavements and have recently entered mainstream design practice through the issue of AASHTO design software. Recent work has been performed to incorporate mechanisms of base reinforcement with geosynthetics into mechanistic-empirical modeling and design. The purpose of this paper is to examine the use of this work for mechanistic-empirical modeling of reinforced unpaved roads by using the same model components used for paved roads and incorporating new components that account for the significant influence of pore-water pressure generation in the subgrade. Results from instrumented unpaved road test sections are used to calibrate and compare with the model predictions. The model provides reasonable predictions of rutting behavior for test sections where rut development is stable, where stable is defined as a rate of rutting that decreases with increasing traffic. The importance of excess pore-water pressure development in the subgrade is illustrated by the test sections and accounted for by the inclusion of steps in the model.© 2012 American Society of Civil Engineers.
Tschegg E.K.,Vienna University of Technology |
Jamek M.,Vienna University of Technology |
Lugmayr R.,TenCate Geosynthetics
Road Materials and Pavement Design | Year: 2012
Geosynthetic interlayers in asphalt systems have become a convenient technology for lifetime prolongation in road construction engineering. Durability and lifetime prediction analysis of such systems can be obtained by fatigue crack growth testing. In this paper, the fatigue crack growth properties of three different asphalt interlayer system groups with different interlayer functions: SAMI (=Stress Absorbing Membrane Interlayer), asphalt reinforcement and the combination of SAMI + asphalt reinforcement are reported. For comparison non-interlayer systems (reference) have also been tested. Instead of 3- or 4-point bending tests with beams, wedge splitting tests with drill cores from the field are used for analyzing the fatigue crack growth behaviour of these systems. Due to the temperature dependence of asphalt the tests have been performed in a climate chamber at -10°C, 0°C and +10°C. Crack growth propagation was determined visually. The results show that this new visual approach for evaluation of crack growth testing together with the wedge splitting test are practicable, reproducible and allow grading of geosynthetic asphalt interlayer systems. © 2012 Taylor & Francis.
Douglas R.A.,Golder Ltd. |
Laprade R.,TenCate Geosynthetics |
Lawrence K.,Golder Ltd.
Transportation Research Record | Year: 2015
The heaviest trucks serving shovel-and-truck mining operations have tripled in weight to more than 600 tonnes gross weight over the past 30 years. The design of haul roads to support these trucks is becoming ever more challenging. An additional problem is the huge demand for aggregates with which to construct these thick, wide roads. In this study of the problem, a numerical modeling investigation was performed for a 300-tonnc-design axle on a granular pavement consisting of a capping layer, base, and subbase (0.5, 1.0, and 1.5 m thick, respectively). Conventional linearly elastic analyses and analyses not permitting tension were carried out. While the results of the conventional elastic analysis permitting tension had indicated that there was no reinforcing effect with these geotextiles, the results of the no-tension analysis indicated a significant reinforcement effect attributable to the inclusion of high-strength geotextiles in the cross section. The results bring into uues-tion the use of analyses permitting tension in the granular pavement materials.
Jamek M.,Vienna University of Technology |
Tschegg E.K.,Vienna University of Technology |
Lugmayr R.,TenCate Geosynthetics
Fatigue and Fracture of Engineering Materials and Structures | Year: 2012
Geosynthetic interlayers in asphalt systems have become a convenient technology for lifetime prolongation in road construction engineering. Established testing methods for characterizing construction materials can be used to describe and evaluate these innovative systems. This study compares three groups of asphalt interlayer systems (stress absorbing membrane interlayer = SAMI, asphalt reinforcement, SAMI + asphalt reinforcement) represented by 10 different geosynthetic interlayers in terms of crack growth resistance and strength. The results will be presented in relation to asphalt reference systems without interlayer. The mechanical and fracture-mechanical properties were determined by means of the wedge splitting test (WST) according to Tschegg and partially by the pull-out test. Due to temperature dependences of the material properties of asphalt, the tests have been performed at -10 °C, 0 °C and +10 °C specimen temperature. © 2012 Blackwell Publishing Ltd.
Plaut R.H.,Virginia Polytechnic Institute and State University |
Stephens T.C.,TenCate Geosynthetics
Geotextiles and Geomembranes | Year: 2012
Geotextile tubes are often used to dewater contaminated or other material. Slurry is pumped into the tube, some of it permeates out through the fabric, and some or all of the particles in the remaining slurry consolidate at the bottom of the tube. This process is often repeated a number of times until the consolidated material (fill) takes up most of the volume in the tube. Interface friction between the fill and the tube may cause a significant increase in the maximum tension in the tube, and may induce failure by tearing. In the analysis of this system here, the tube is assumed to be long and a cross section is analyzed. The tube material is assumed to be inextensible with no bending stiffness, the tube weight is neglected, the foundation is rigid and horizontal, the slurry is modeled as a liquid, and friction acts between the fill and the tube. The relevant parameters are the tube circumference and height, the specific (unit) weights of the slurry and the fill, the height of the fill, and the coefficient of friction. The equations are derived and solved numerically, and the effects of the parameters on the tube behavior are investigated. Friction has a negligible effect on the cross-sectional area. However, the maximum tension, occurring at the top of the tube, increases as the coefficient of friction increases, and can be significantly greater than the value predicted by standard procedures that neglect friction. © 2012 Elsevier Ltd.
Lacina B.A.,TenCate Geosynthetics
American Association of Textile Chemists and Colorists International Conference 2010 | Year: 2010
The discussions in this document have conclusively shown that geotextiles are a time-proven and cost-effective method for providing a durable solution for long-term and short-term roadway performance. The proper geotextile can reduce long-term maintenance costs for a permanent roadway, as well as reduce up-front construction material costs, if so desired. We have also shown that subgrade stabilization using geotextiles can significantly reduce undercut requirements for soft subgrade soils and allow site access for construction equipment where it would otherwise be impossible. With the very high benefit to cost ratio that geotextiles provide in roadway applications, we have to wonder why they are not routinely used in all roadway construction. Based on the readily available information from credible sources such as FHWA, AASHTO and profuse research publications, it seems that owners are throwing their hard-earned money away by not using geotextiles in construction of their roadways. In today's economic climate, cost savings and project life-cycle improvement are imperative, meaning geotextiles should be used in every roadway project. By not using the available geotextile knowledge base, we are not providing the public the best possible and most economic roadway construction solutions.
Lostumbo J.M.,TenCate Geosynthetics
Geotechnical Special Publication | Year: 2010
Yeager Airport was constructed atop mountainous terrain near Charleston, WV in the 1940's. Construction consisted of excavating 7 hilltops and filling surrounding valleys to create a flat site for the runways. Due to this dramatic terrain, development to meet FAA safety regulations was extremely difficult, and some concessions were allowed. However, the airport recently needed to extend Runway 5 approximately 150 meters (500 feet) in order to meet current FAA safety regulations. Bridges, walls and reinforced slopes were evaluated as options to extend the runway. The geosynthetic reinforced slope option provided the most economical alternative; plus, the "green" faced system allowed for a more aesthetically pleasing alternative to blend into the surrounding green hills. The reinforced structure is a 1H:1V (45 degree) geosynthetic reinforced steepened slope, 74 meters (242 feet) high. This is the tallest geosynthetic reinforced green faced 1H:1V slope constructed in the United States. © 2010 ASCE.
Artieres O.,TenCate Geosynthetics
Optics InfoBase Conference Papers | Year: 2010
A textile fibre optics composite sensor aims to monitor geotechnical structure and to generate early warnings if it detects and localizes the early signs of malfunctioning, such as leaks or instability. This is a customizable solution: Fiber Bragg gratings, Brillouin and Raman scattering can be built into this system. These technologies measure both strain and temperature changes in soil structures. It can provide a leak and deformation location within accuracies resp. 0.02% and 1 l/min/m. © 2010 Optical Society of America.
Gale S.M.,Gale Tec Engineering Inc. |
Kurtz M.,TenCate Geosynthetics |
Chuck F.,TenCate Geosynthetics |
Janse D.,TenCate Geosynthetics
Geosynthetics | Year: 2013
The article reviews the types of geotextiles and geogirds used on various subgrades and water conditions for high-demand, short-term gravel access roads on renewable wind energy projects throughout Europe and North America through a series of case histories. The location of a renewable energy project is based on many technical and political issues. The European Union (EU) installed 9.6 gigawatts of wind energy construction in 2011, bringing the total installed capacity to nearly 94 GW, enough to supply 6% of the EU's electricity demand according to the European Wind Energy Association. Germany has the most installed EU capacity followed by Spain, France, Italy, and the UK. It was concluded from some of the early test sections within highway projects in the Netherlands that elongation at break for reinforcing geotextiles should be below 10% fabric modulus at the working load should be in the range of 5% elongation, and the strength should be at least 150 kN/m.