Abstract
In recent years, environmental concerns related to the overexploitation of natural resources and the need to manage large amounts of wastes arising from construction activities have intensified the pressure on the civil engineering industry to adopt sustainable waste recycling and valorisation measures. The use of recycled construction and demolition (C&D) wastes as alternative backfill for geosynthetic-reinforced structures may significantly contribute towards sustainable civil infrastructure development. This paper presents a laboratory study carried out to characterise the interaction between a fine-grained C&D material and two different geogrids (a polyester (PET) geogrid and an extruded uniaxial high-density polyethylene (HDPE) geogrid) through a series of large-scale pullout tests. The effects of the geogrid specimen size, displacement rate and vertical confining pressure on the pullout resistance of the geogrids are evaluated and discussed, aiming to assess whether they are in line with the current knowledge about the pullout resistance of geogrids embedded in soils. Test results have shown that the measured peak pullout resistance of the geogrid increases with the specimen size, imposed displacement rate and confining pressure. However, the pullout interaction coefficient has exhibited the opposite trend with the specimen size and confining pressure. The pullout interaction coefficients ranged from 0.79 and 1.57 and were generally greater than or equal to the values reported in the literature for soil-geogrid and recycled material-geogrid interfaces.
Highlights
Recent years have witnessed an increasing environmental awareness and the recognition of the importance of reducing the production of wastes and the exploitation of non-renewable natural resources in order to foster sustainable development
The aim of the present study is assessing whether the effects of the different parameters with influence on the pullout resistance of geogrids when they are embedded in a construction and demolition (C&D) recycled material are in line with the current knowledge about the pullout resistance of geogrids in soils
The plotted data show that, regardless of the confining pressure applied in the tests, the increase in specimen size from 200 mm × 600 mm to 250 mm × 750 mm led to an increment in the peak pullout resistance of the geogrid
Summary
Recent years have witnessed an increasing environmental awareness and the recognition of the importance of reducing the production of wastes and the exploitation of non-renewable natural resources in order to foster sustainable development. Geotechnical design and construction, which is often placed early in a civil engineering project, can significantly contribute to enhance the overall sustainable development by incorporating sustainable practices, among which is the use of alternative, environment friendly materials and the reuse of waste materials, such as the C&D wastes [4,5,6]. In Europe about 40% of the natural aggregates are consumed in unbound layers of transportation infrastructures [7]. This suggests that the reliance on natural aggregates in geotechnical applications is high and the inclusion of recycled aggregates can contribute significantly to preserve the environment. In view of the above, several studies have recently been conducted to evaluate the feasibility of using recycled C&D wastes in diverse geotechnical applications, such as ground improvement works [8,9], pipe bedding and backfilling [10,11], construction of paved and unpaved roads [12,13,14,15,16,17,18] and backfilling of geosynthetic-reinforced structures [19,20,21,22]
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call