Mechanistic Laboratory Evaluation and Field Construction of Recycled Concrete Materials for Use in Road Substructures

Abstract

Given the renewal of urban infrastructure and the increased costs of landfilling concrete rubble materials, opportunities exist to optimize the reclamation and recycling of portland cement concrete (PCC) and hot-mix asphalt concrete (HMAC) rubble through their innovative use in road rehabilitation. The primary objective of this study was to demonstrate the ability to reclaim, process, and recycle stockpiled concrete materials to provide improved structural mechanistic–climatic material properties and to meet or exceed the mechanical properties of conventional granular road materials. This research was based on advancements made in 2009 as part of the Green Streets Infrastructure Program in the city of Saskatoon, Saskatchewan, Canada. A second objective of this research was to pilot the field application of reclaimed and recycled HMAC and PCC rubble in typical urban road reconstruction applications. Recycled HMAC and PCC materials were used in the pilot reconstruction of a road that was exhibiting substructure moisture problems and structural failure. This study showed that recycled HMAC and PCC rubble materials could be processed to achieve mechanistic laboratory properties that exceeded those of conventional granular-based materials. This study also demonstrated efficient constructability and high end-product structural asset value of a typical rehabilitated urban road structure test section in the city of Saskatoon by using recycled HMAC and PCC rubble. On the basis on these findings, the use of quality processed HMAC and PCC rubble materials for road reconstruction was found to be a technical and environmentally sustainable solution.

Modeling in Situ Performance of Cement-Stabilized Granular Base Layers of Urban Roads

“…The granular base layer is an important component in pavement structure designs, as it protects the subgrade and provides drainage for the pavement structure (2). Areas with concentrated truck haul and poor-quality aggregate have experienced road performance that Crushed PCC and RAP can be used in a pavement structure as fill (subbase), drainage layer, and base layer (1)(2)(3)(5)(6)(7). Saskatchewan agencies have undertaken efforts to recycle and reuse concrete aggregates.…”

“…In Saskatchewan, crushed PCC and RAP material have been used as base material, backfill material, drainage rock, and subbase material. Using recycled aggregates in road construction has many environmental and economic benefits: conservation of virgin aggregates, reduction in the impact on landfills, limitations on haul distance when crushed locally, reduction in disposal and transportation costs, and reduction in overall cost compared with procurement of virgin aggregates (7). In many studies, the performance of recycled PCC in a base layer has been comparable to that of virgin granular aggregate (8-11).…”

“…Finding high-quality aggregate materials in Saskatchewan is a challenge, as good-quality aggregate sources are becoming depleted, especially in urban areas (3,7). Haul distances as long as 100 km result in higher costs, energy consumption, and haul road damage (7). Optimizing the use of locally available aggregate sources is economically and environmentally beneficial.…”

The Use of Glass to Optimize Bitumen Absorption of Hot Mix Asphalt Containing Recycled Construction Aggregates

“…Referring to available literature e.g., [ 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 ], RCA has been used in the base course and subbase course of pavements over the last two decades. However, few research studies [ 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 ] have reported the utilization of RCA in HMA.…”

Evaluation of Mechanical Properties of Recycled Material for Utilization in Asphalt Mixtures

“…Among the recycled aggregates that can be utilized in asphalt mixture, RCA obtained from construction and demolition waste constitute a major part of generated solid waste as a result of renovation and construction projects. Referring to literature survey (e.g., Arulrajah [38][39][40][41][42]. Accordingly, in this research, the properties of RCA have been thoroughly evaluated through the laboratory investigation and tests.…”