Author: Publisher:
ISBN:
Category : Pavements, Concrete
Languages : en
Pages : 107
Book Description
Evaluation of Recycled Concrete as Aggregate in New Concrete Pavements
Author: Evaluation of Recycled Concrete for Use as Aggregates in New Concrete Pavements
Author: Daniel Gilbert MjeldeEvaluation of Recycled Aggregates Test Section Performance
Author: Farhad RezaPublisher:
ISBN:
Category : Aggregates (Building materials)
Languages : en
Pages : 195
Book Description
The need to consider sustainability in design dictates that materials should be recycled and reused whenever possible. The Minnesota Department of Transportation (MnDOT) is quite progressive in allowing the use of recycled aggregates in new construction. While the use of recycled concrete aggregate (RCA) in the base course of new pavements is quite common in Minnesota and many other states, it is rarely used in the concrete pavement itself. In fact, Minnesota was one of the few states to build multiple trial projects and has one of the largest number of concrete pavements constructed using the RCA in the concrete itself. The performance of those pavements, most of which are still in service, has never been formally evaluated against similar conventional concrete pavements. This prompted the current research study. Additional objectives were to assess the current state of practice across the nation, conduct experimental investigations using RCA in concrete, assess the sustainability and in particular the economics of using RCA in concrete, and finally to provide some recommendations for guidelines on using RCA in concrete. It has been shown by the authors and other researchers that it is possible to create strong and durable concrete mixtures using RCA as coarse aggregate in volume replacement levels of natural coarse aggregate up to 100%.
Design and Control of Concrete Mixtures
Author: Steven H. KosmatkaPublisher:
ISBN:
Category : Technology & Engineering
Languages : en
Pages : 224
Book Description
Portland Cement Association reference, dealing with fundamentals, cold weather concreting, curing, admixtures, aggregates, mixing, and much more.
Evaluation of Recycled Concrete for Use as Aggregates in New Portland Cement Concrete Pavements
Author: Spencer Ray BoyleEvaluation of Recycled Concrete Aggregate Produced from Demolished Runway Panels as a Substitute for Coarse Aggregates in New Portland Cement Pavements
Author: Timothy Charles SpryNew Trends in Recycled Aggregate Concrete
Author: Jorge de BritoPublisher: MDPI
ISBN: 3039211404
Category : Technology & Engineering
Languages : en
Pages : 280
Book Description
This book is the result of a Special Issue published in Applied Sciences, entitled “New Trends in Recycled Aggregate Concrete". It identifies emerging research areas within the field of recycled aggregate concrete and contributes to the increased use of this eco-efficient material. Its contents are organised in the following sections: Upscaling the use of recycled aggregate concrete in structural design; Large scale applications of recycled aggregate concrete; Long-term behaviour of recycled aggregate concrete; Performance of recycled aggregate concrete in very aggressive environments; Reliability of recycled aggregate concrete structures; Life cycle assessment of recycled aggregate concrete; New applications of recycled aggregate concrete.
Evaluation of the use of recycled concrete aggregate for concrete pavement
Author: Christopher Charles PankeyPublisher:
ISBN:
Category :
Languages : en
Pages : 134
Book Description
Evaluation of Recycled Portland Cement Concrete Pavements for Base Course and Gravel Cushion Material
Author: Allen L. CooleyPublisher:
ISBN:
Category : Pavements
Languages : en
Pages : 106
Book Description
Based upon the work conducted in this study, it was concluded the recycled portland cement concrete pavements are available as an option for the construction of gravel cushion and aggregate base course layers.
Evaluation of Low-quality Recycled Concrete Pavement Aggregates for Subgrade Soil Stabilization
Author: Masoumeh TavakolPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Recycled concrete aggregate (RCA) is the byproduct of the demolition of concrete structures and pavements. An estimated 140 million tons of concrete waste is produced annually in the United States, most of which ends up in landfills. The use of RCA to replace quarried aggregates in paving projects is one way to utilize these materials and alleviate concerns regarding this increasing waste stream. RCA usage prevents waste concrete disposal into landfills, resulting in more sustainable use of mineral aggregate sources, and may further reduce costs associated with paving projects. However, the inferior physical properties of RCA, such as the presence of recycled mortar, complicate the incorporation of RCA into new concrete mixtures. State highway agencies such as the Kansas Department of Transportation are facing further issues with RCA from D-cracked pavements, raising the question if D-cracked aggregates should be used in paving operations. No known work has evaluated the effect of RCA from D-cracked pavements in subgrade soil stabilization. This study stabilized a low-plasticity clay in Kansas using RCA and three stabilizing materials (lime, Class C fly ash, and a combination of Portland cement and fly ash). Candidate mixtures with varying proportions of chemical stabilizers and D-cracked aggregates were evaluated using the standard Proctor, unconfined compressive strength, linear shrinkage, and California Bearing Ratio tests. Microstructure characteristics of selected mixtures were explored using scanning electron microscopy (SEM) and energy dispersive X-ray tests. Laboratory test results indicated that RCA, in conjunction with all cementitious materials except lime, improved clay strength, stiffness, and shrinkage properties. SEM results indicated that RCA caused a low void space and a dense arrangement of soil particles. RCA effectively improved evaluated mixture properties when an adequate soil-RCA bond was reached using chemical agents. The long-term performance of full-depth flexible pavements with stabilized mixtures as subgrade was assessed in the AASHTOWare Pavement ME Design (commonly known as MEPDG) software. The life-cycle cost of flexible pavements with stabilized mixtures was estimated for a 40-year design period. Economic analysis results indicated that RCA was cost effective only if it was used with a combination of fly ash and Portland cement.