Experimental Study on Resilient Behavior of Geocell-reinforced Recycled Asphalt Pavement Base Layer PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Experimental Study on Resilient Behavior of Geocell-reinforced Recycled Asphalt Pavement Base Layer PDF full book. Access full book title Experimental Study on Resilient Behavior of Geocell-reinforced Recycled Asphalt Pavement Base Layer by Manikanta Saladhi. Download full books in PDF and EPUB format.
Author: Manikanta Saladhi
Publisher:
ISBN:
Category :
Languages : en
Pages : 105
Get Book Here
Book Description
Recycled Asphalt Material (RAP) is defined as removed and reprocessed pavement materials containing asphalt and aggregates. These materials are obtained when asphalt pavements are removed for the rehabilitation and maintenance of distressed pavements. The use of RAP as a base/subbase aggregate in pavement construction is technically and environmentally a sustainable solution, and conserve use of natural resources by requiring less virgin aggregate in pavement construction. Past studies showed that the use of 100% RAP as base course lacks shear strength and can undergo large deformations. Geocells are a system of threedimensional, interconnected, honeycombed cellular structures that resist the lateral expansion of soil particles and act like a slab to distribute surface loads over a larger area of the foundation soil. Most of the recent studies on geocell-reinforced RAP bases show that they improve the pavement service life, strength and stiffness of base layer. The main objective of this research was to develop and construct a large-scale laboratory test setup, which was used to perform a series of cyclic plate load tests to examine resilient behavior of geocell-reinforced RAP bases. Six large-scale laboratory cyclic plate load tests and two static plate load tests were conducted on unreinforced and geocell-reinforced RAP base road sections. The unpaved road sections consisted of moderate subgrade, unreinforced/geocell-reinforced RAP base, and a RAP cover. The test results showed that the geocell-reinforcement improved the performance of RAP bases. The high hoop strength of the geocell reinforcement provided more confinement and offered additional resistance against lateral movement of RAP base. The geocell reinforcement significantly reduced the permanent and resilient deformations of RAP base when compared to that of unreinforced RAP bases, thereby increasing resilient modulus of the reinforced base layer. The geocellreinforced RAP base layer acted as a stiff mattress foundation and resulted in lower compression of RAP base and subgrade. The geocell reinforcement significantly reduced the permanent deformations of RAP base approximately by 50% when compared to that of unreinforced RAP base. Additionally, the geocell reinforcement had increased resilient modulus of RAP base by a factor of 3.0, compared to that of unreinforced RAP base.
Author: Manikanta Saladhi
Publisher:
ISBN:
Category :
Languages : en
Pages : 105
Get Book Here
Book Description
Recycled Asphalt Material (RAP) is defined as removed and reprocessed pavement materials containing asphalt and aggregates. These materials are obtained when asphalt pavements are removed for the rehabilitation and maintenance of distressed pavements. The use of RAP as a base/subbase aggregate in pavement construction is technically and environmentally a sustainable solution, and conserve use of natural resources by requiring less virgin aggregate in pavement construction. Past studies showed that the use of 100% RAP as base course lacks shear strength and can undergo large deformations. Geocells are a system of threedimensional, interconnected, honeycombed cellular structures that resist the lateral expansion of soil particles and act like a slab to distribute surface loads over a larger area of the foundation soil. Most of the recent studies on geocell-reinforced RAP bases show that they improve the pavement service life, strength and stiffness of base layer. The main objective of this research was to develop and construct a large-scale laboratory test setup, which was used to perform a series of cyclic plate load tests to examine resilient behavior of geocell-reinforced RAP bases. Six large-scale laboratory cyclic plate load tests and two static plate load tests were conducted on unreinforced and geocell-reinforced RAP base road sections. The unpaved road sections consisted of moderate subgrade, unreinforced/geocell-reinforced RAP base, and a RAP cover. The test results showed that the geocell-reinforcement improved the performance of RAP bases. The high hoop strength of the geocell reinforcement provided more confinement and offered additional resistance against lateral movement of RAP base. The geocell reinforcement significantly reduced the permanent and resilient deformations of RAP base when compared to that of unreinforced RAP bases, thereby increasing resilient modulus of the reinforced base layer. The geocellreinforced RAP base layer acted as a stiff mattress foundation and resulted in lower compression of RAP base and subgrade. The geocell reinforcement significantly reduced the permanent deformations of RAP base approximately by 50% when compared to that of unreinforced RAP base. Additionally, the geocell reinforcement had increased resilient modulus of RAP base by a factor of 3.0, compared to that of unreinforced RAP base.
Author: Anu Muthumala George
Publisher:
ISBN:
Category : Asphalt concrete
Languages : en
Pages : 254
Get Book Here
Book Description
Reclaimed asphalt pavement (RAP) materials have been considered as one of the most sustainable and cost-effective options in the pavement industry. The use of RAP materials in pavement construction reduces natural resources depletion and the volume of construction debris discarded into the landfills. However, the low shear strength and high permanent deformation (PD) of RAP materials often limit their application in road bases. Utilization of mechanical stabilizers, such as geocell, for stabilizing RAP bases, have found to be effective in improving the pavement performance. The main objective of this study is to assess the efficacy of high-density polyethylene (HDPE) geocell reinforcements in enhancing the strength and stiffness properties of RAP bases and for mitigating PD behavior. In this dissertation research, several large-scale static and repeated load tests were performed on the unreinforced RAP base (URB) and geocell-reinforced RAP bases (GRRB) over clay subgrade. The performance of the geocell reinforcement was evaluated based on various parameters including bearing capacity (q), elastic deformation (ED), PD, resilient modulus (Mr), traffic benefit ratio (TBR), and rut depth reduction (RDR). Test results showed that the HDPE geocell layer increased the Mr and reduced the PD of the RAP base layer when compared to URB. Numerical models of the GRRB sections were developed to assess the load transfer mechanism of geocell reinforcement under static and dynamic loading. These models were developed in FLAC3D (special character) software by employing finite-difference (FD) approach. The unreinforced and reinforced FD models were validated with experimental results and a good agreement between both was observed. The validated FD model was then used to perform parametric studies to assess the factors affecting the performance of geocell-reinforced bases. Additionally, a life-cycle assessment (LCA) and life-cycle cost analysis (LCCA) were performed to estimate the current and future cost of the pavement section with GRRB. This analysis considered agency, user, environmental, and health impact costs incurred during the service life of the pavement section. Finally, an LCA-LCCA framework was developed to assess the sustainability of the pavement infrastructure using a sustainability index. The results showed that the GRRB can be successfully used as a sustainable and cost-effective replacement for virgin aggregate bases. The findings from this research would aid in the development of design charts for assessing the response of geocell-reinforced pavement bases under static and repeated loading.
Author: Christopher William LaRoche Nelsen
Publisher:
ISBN:
Category :
Languages : en
Pages : 340
Get Book Here
Book Description
Geocells are a growing type of geosynthetic product used in many applications, including the reinforcement of unbound granular materials for the construction of flexible pavements. Although significant research has been conducted to quantify the performance of geocell-reinforced soil masses, there is no universally accepted design method for these structures. The Mechanistic-Empirical Pavement Design Guide (MEPDG) is a solid framework on which to base a geocell design method. The resilient modulus of a material is constitutive relationship between the imposed stress state and the resilient strain. It is the relevant design parameter that should be modified in the MEPDG for the design of pavement structures using geocells. However, a more robust understanding of the behavior and mechanisms that contribute to the overall performance of geocell-reinforced materials is necessary to develop theoretically-sound model. As such, the materials and equipment necessary to conduct a thorough analysis of geocells were conceived and implemented as part of this study. This equipment is based around the transparent soil concept – transparent soils are two-part media consisting of solid particles and a saturating fluid with matching refractive indices. Fused quartz and mineral oil were selected as appropriate materials to use as a granular soil surrogate. The large-scale equipment consists of a steel-framed tank with cast acrylic sides. Many lessons were learned with regard to the use of transparent soil techniques in large-scale experiments. Preliminary results indicate the equipment is adequate to validate the results of prior geocell experiments. Additional improvements will allow for the full utilization of transparent soil capabilities and the direct observation of geocell reinforcement behavior and mechanisms in-situ.
Author: Sujit Kumar Dash
Publisher: Frontiers Media SA
ISBN: 2889667413
Category : Technology & Engineering
Languages : en
Pages : 107
Get Book Here
Book Description
Author: Sunil K. Sirigiripet
Publisher: ProQuest
ISBN: 9780549319061
Category : Civil engineering
Languages : en
Pages :
Get Book Here
Book Description
Natural aggregates derived from a variety of source rocks have been used as a road base material. But the extraction of natural aggregates resources is increasingly being constrained by urbanization, increased costs and environmental concerns. Thus, increased amounts of reclaimed materials are being used to supplement natural aggregates in road construction. Recycled Asphalt Pavement (RAP) material is one of the important recycled materials used in the present geotechnical applications. Many agencies are constantly seeking to reap the benefits of utilizing RAP. Main advantages of utilizing RAP include the preservation of the existing profile, conservation of asphalt and aggregate resources, conservation of energy, and reduction in life-cycle cost. Therefore, it is no surprise that state highway agencies have been moving toward increasing the percentages of RAP in their HMA pavements. The 1993 EPA report mentioned that approximately 73 million tons of asphalt pavement material was recycled annually, which amounts to about 80% of the asphalt removed from pavements each year. Quarry by-products are another important recycled materials showing good performance in many geotechnical applications. These are generally obtained from crushed natural stone. One of the fines obtained from limestone stone quarries are becoming popular. These fines when they are stabilized with some cementing materials can be used in any geotechnical applications. About 159 million metric tons (175 million ton) produced annually is thought to be used in many geotechnical applications. In a recent survey, three states (Arizona, Illinois, and Missouri) indicated that quarry by-products have been used as an embankment material and three other states (Florida, Georgia, and Vermont) indicated some use of quarry by-products in base or subbase for the pavement applications. These are also used as mineral filler in asphalt paving. In this present research, a comprehensive experimental program was performed on two recycled materials which include RAP and Cemented Quarry Fines (CQF) which were used as a pavement base material. All the tests provided repeatable and reliable results. Unconfined Compressive Strength (UCS) tests showed a peak stress of 1200 kPa for the CQF which was 12 times more than the untreated sample. UCS for the RAP material showed a strength of 340 kPa which was expected for the RAP materials. Peak values for the resilient modulus for RAP and CQF were 330 MPa and 370 MPa respectively. These samples required more number of cycles to know the actual resilient modulus. Untreated sample showed a peak value of 220 MPa. Values for the swell tests was zero for the CQF whereas for the untreated sample was around 6%. RAP showed a less strain of 0.7% which is negligible for these materials. Consolidation Indices for these recycled materials showed values less than 0.001. Field monitoring data showed that the settlements and pressures were in permissible limits. Results from the experimental program along with field monitoring data showed that these recycled materials are very best suited as a pavement base material. Based on these results these recycled materials can be used for future research projects.
Author: Kenneth Reifsnider
Publisher: Woodhead Publishing
ISBN: 012818261X
Category : Technology & Engineering
Languages : en
Pages : 464
Get Book Here
Book Description
Durability of Composite Systems meets the challenge of defining these precepts and requirements, from first principles, to applications in a diverse selection of technical fields selected to form a corpus of concepts and methodologies that define the field of durability in composite material systems as a modern discipline. That discipline includes not only the classical rigor of mechanics, physics and chemistry, but also the critical elements of thermodynamics, data analytics, and statistical uncertainty quantification as well as other requirements of the modern subject. This book provides a comprehensive summary of the field, suited to both reference and instructional use. It will be essential reading for academic and industrial researchers, materials scientists and engineers and all those working in the design, analysis and manufacture of composite material systems. Makes essential direct and detailed connections to modern concepts and methodologies, such as machine learning, systems controls, sustainable and resilient systems, and additive manufacturing Provides a careful balance between theory and practice so that presentations of details of methodology and philosophy are always driven by a context of applications and examples Condenses selected information regarding the durability of composite materials in a wide spectrum of applications in the automotive, wind energy, civil engineering, medical devices, electrical systems, aerospace and nuclear fields
Author: Noor Amila Wan Abdullah Zawawi
Publisher: CRC Press
ISBN: 1498781519
Category : Science
Languages : en
Pages : 567
Get Book Here
Book Description
Engineering Challenges for Sustainable Future contains the papers presented at the 3rd International Conference on Civil, Offshore & Environmental Engineering (ICCOEE2016, Kuala Lumpur, Malaysia, 15-17 August 2016), under the banner of World Engineering, Science & Technology Congress (ESTCON2016). The ICCOEE series of conferences started in Kuala Lumpur, Malaysia 2012, and the second event of the series took place in Kuala Lumpur, Malaysia 2014. This conference series deals with the civil, offshore & environmental engineering field, addressing the following topics: • Environmental and Water Resources Engineering • Coastal and Offshore Engineering • Structures and Materials • Construction and Project Management • Highway, Geotechnical and Transportation Engineering and Geo-informatics This book is an essential reading for academic, engineers and all professionals involved in the area of civil, offshore and environmental engineering.
Author: Sita Timsina
Publisher:
ISBN:
Category :
Languages : en
Pages : 118
Get Book Here
Book Description
The recycled materials such as, Recycled Crushed Concrete Aggregates (RCCA) and Reclaimed Asphalt Pavement (RAP) treated with cement has been widely used as the alternative granular base in pavement construction in different states in USA due to the depletion of natural resources of virgin aggregates. While a number of factors drive the use of these recycled materials, the two primary factors are economic savings and environmental benefits. In the flexible pavement systems, the base layer contributes to the structural capacity of the pavement systems, so, the quality performance of this layer is essential. However, presence of fine particles in the pavement system promotes the contamination of coarse granular material due to migration of fines from the subgrade which might adversely affect the strength and stiffness of flex-base. As such, the main purpose of this study was to examine the effect of fine contents in granular base materials in terms of strength and stiffness. In this research, a comprehensive experimental program was designed to characterize resilient and compressive behavior of recycled materials in the presence of soil in both natural and stabilized forms. For this study, RAP and RCCA were mixed at different proportions from 0% to 100% with different amount of soil mixture varying between 0% and 24% with cement content ranging from 0% to 6% at 2% interval. Different laboratory tests were conducted to determine the Optimum Moisture Content (OMC), Maximum Dry Density (MDD), Unconfined Compressive Strength (UCS) and Resilient Modulus (MR) of the mixes of RAP, RCCA, soil and Ordinary Portland Cement (Type I/II). Based on the preliminary data, it was found that with the intrusion of fines in cement treated as well as untreated recycled granular bases, both the strength and stiffness decrease as compared with the same specimens without fine particles. With the addition of 12% and 24% of soil in the combination of 30% RAP + 70% RCCA and 50% RAP + 50% RCCA, the value of resilient modulus decreased in the range of 30 -55% in the cement stabilized as well as natural forms. For example,the Mr value of (30/70) RAP/RCCA with 2% cement ranged between 10,000 psi and 45,000 psi, it was reduced to a range of 10,000-30,000 psi with 12% soil intrusion. Similarly, at 6% cement content the Mr value of (30/70) RAP/RCCA the highest value of resilient modulus of 75,000 psi was observed whereas with the 12% soil, the moduli value was reduced to 38,000 psi at the given maximum confining pressure of 20psi.
Author: Woosung Kim
Publisher:
ISBN:
Category :
Languages : en
Pages : 372
Get Book Here
Book Description
Author: David Jones
Publisher: CRC Press
ISBN: 0203073010
Category : Technology & Engineering
Languages : en
Pages : 560
Get Book Here
Book Description
Pack: Book and CDInternationally, full-scale accelerated pavement testing, either on test roads or linear/circular test tracks, has proven to be a valuable tool that fills the gap between models and laboratory tests and long-term experiments on in-service pavements. Accelerated pavement testing is used to improve understanding of pavement behavior,
