Conference Agenda

Concrete piles and geosynthetic reinforcements are commonly used to reduce settlements at the top of embankments. The use of geosynthetic layers at the embankment bottom leads to several advantages: (i) faster construction, (ii) better control of differential settlements and (iii) a fewer number of piles is needed for equal admissible settlements at the embankment top. Because of the latter point, the use of geosynthetic reinforcement reduces the Embodied Carbon related to concrete. Unfortunately, since existing design methods for Geosynthetic-Reinforced and Pile-Supported embankments do not allow to calculate settlements at the embankment top, they cannot be used to optimize the number of concrete piles to increase sustainability. In this note, an innovative model for assessing settlements induced by the embankment construction pro-cess is applied to the preliminary design stage of a practical example. The mass of CO2 saved by using geosynthetics and optimizing the number of piles is calculated.

<p>During the PVC geomembrane installation for waterproofing of tunnels and structures and in order to mechanically protect the product, we usually pour a 6 cm thick slab of concrete. This screed allows the installation of bars for the internal structure.</p>

<p>After dynamic and static tests, we realize that we can use cementitious geocomposites instead of this on site poured concrete. In fact the presence of big quantity of polypropylene fibers in the product offers a subsequent resistance which is sufficient in most of the cases.</p>

<p>It has a real impact on resiliency as the use of this type of product instead of a thick concrete slab is reducing: 1. the depth for the digging and 2. the quantity of concrete poured on site.</p>

<p>The example of this use in tunneling application can be used in many other situation for protection: basins, basements, buried structures, temporary protection… offering on each project a reduction of energy comparing to traditional solutions.</p>

<p>Lowering the Carbon Footprint is one of the strongest advantages by using HDPE geomembranes instead of traditional way for waterproofing as compacted clays.</p>

<p>A 1.5mm HDPE liner could give similar watertight as 0.60m compacted of high quality and homogeneous clay with lower permeability than 1x10-11 m/sec (ASTM D 5887). Based on several scientist survey, considering all resources and energy to become either products as waterproofing barrier, the geosynthetics (geomembrane HDPE 1.5mm) takes up lower carbon dioxide equivalent, therefore it is more environmentally friendly solution.</p>

<p>Features of HDPE Geomembrane and its Carbon Footprint.</p>

<p>The main component of HDPE is the monomer ethylene, which is polymerized to form polyethylene. The main catalysts are aluminum trialkylitatanium tetrachloride and chromium oxide.</p>

<p>The polymerization of ethylene and co-monomers into HDPE occurs in a reactor in the presence of hydrogen at a temperature of up to 110º Celsius degrees (230 degrees Fahrenheit).</p>

<p>The resulting HDPE powder is then fed into a pelletizer to make pellets.</p>

<p>Then, SOTRAFA, as a manufacturer with latest technology in calandred system (flat die), makes geomembrane Alvatech HDPE from these pellets. The Geomembrane Alvatech HDPE keeps its outstanding features constantly either dry season or wet season.</p>

<p><strong>The Paragon Park phase 3 project consisted of constructing a 9.5m high noise bund 400m in length between a new housing development and a metal recycling facility located in Coventry, Stoney Stanton Road which is located in a densely populated area.</strong></p>

<p><strong>One challenging aspect of the project was the soil conditions and the fill material, where site won material was to be considered to reduce the overall cost therefore avoiding the use of imported material which would also reduce the disturbance to the local community and travelers during the day. The face of the bund was also a challenge as the client wanted an aesthetic face therefore we had to consider what possible solutions could be installed on the 70 degree steep face. </strong></p>

<p><strong>The bund was built on top of a well prepared and compacted started layer and the site won material was used for the build-up of the bund with multiple layers of geogrid at various length to reduce the material cost. Within the face a rivel mesh system was used to keep the topsoil soil retained at the face with the use of the erosion control mat wraparound and help achieve the 70 degrees as each layer was constructed to the height of 9.5m. </strong></p>

<p><strong>The key elements used to construct the bund: Geotextile Ekotex (nonwoven) used for separation between the different soil materials used for the project, Geogrid Strata to strengthen each layer of the bund, Erosion Control Landlok to achieve a vegetated face and a rivel mesh system to help achieve a 70deg face throughout each layer of buildup.</strong></p>

<p><strong>The project was designed using the programs of Reslope and Ressa following the British Standards BS8006:2010 internal stability, Partial Factors and Interaction Factors.</strong></p>

The uncontrolled generation and dispersion of plastic debris and microplastics in the environ-ment and particularly in the oceans has become a global problem. The present paper intends to critically analyse the source and quantities of microplastic debris produced by geosynthetics vs the environmental benefits afforded by geosynthetics. The paper considers the environmental innovation in the geosynthetics industry. Some fake news which associate geosynthetics to detrimental effects like the generation of plastic debris and microplastics are critically ana-lysed. It is shown that in reality the advantages of geosynthetics are much larger than disad-vantages, while detrimental effects are absolutely minimal. The conclusions highlight the un-disputable fact that the generation of plastic debris and microplastics from geosynthetics is very limited, and lower than the quantities of microplastics generated by alternative solutions.

<p>The use of reinforcement geosynthetics to prevent localized collapses over cavities is now relatively common. During the REGIC (Reinforcement using Intelligent Geosynthetics over Natural or Anthropic Cavities) research project, an innovative geosynthetic solution has been developed. It includes a specific reinforcement geosynthetic coupled with an autonomous and remote warning device to detect, to locate and then monitor a localized collapse or sinkhole under an embankment. This warning system includes a network of optical fibre sensors placed on the geosynthetic and connected to a measuring box. This monitoring system allows providing an interesting solution for a quick and efficient risk management. The objective of this study is to identify technically and environmentally the implementation conditions validating the expected benefits of this innovative instrumented geosynthetic solution compared to the traditional reinforcement solution. The Life Cycle Analysis is realized to carry out this comparison from an environmental point of view. The results of this comparative study aim to provide information on the environmental performance of the developed instrumented solution in a research and development framework. A sensitivity analysis is carried out to identify the most influential parameters. This analysis gives an overview of the environmental performance of the solution developed during the REGIC project. This detailed analysis is then extended to most current other possible solutions responding to the reinforcement of a cavity, which provide the same level of performance and safety to the client. This life cycle analysis finally resulted in the publication of an EPD® for the geosynthetic range concerned.</p>

Pit Thermal Energy Storages sealed with geomembranes have proven to be vital applications for long term storage of solar thermal energy or excess heat in large volumes at affordable costs. Energy content and its utilization depends on the system integration, so does the tem-perature profile, which impacts the liner material lifetime. During the transformation of ener-gy systems a thorough demand for energy storage can be expected in the future. The project in Høje Taastrup vastly increases scope of functions as permanent high temperatures (≥90°C) enable more advanced operation strategies with additional measurable economic outcomes for operators. For lifetime prediction of liner materials, a methodological approach was imple-mented based on micro-specimen. Due to the reduction of specimen thickness an acceleration factor of up to 20 was achieved. The best performing novel PP-HTR liner material revealed a predicted lifetime of up to 35 years at a temperature loading profile ranging from 60-90°C.