Author: Mehran Mazari
Publisher:
ISBN:
Category : Concrete, Pavement
Languages : en
Pages :

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Book Description

Author: Xiong Zhang
Publisher:
ISBN:
Category :
Languages : en
Pages : 0

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Book Description
"Conventional density-based methods of compaction quality assurance (QA) using nuclear density gauges (NDG) have been the practice for many years. However, NDG testing becomes less desirable because of safety, regulatory, and cost concerns. In addition, density is not a direct input to the structural design of the pavements and is not directly linked to pavement performance. In recent years, modulus-based compaction QA of unbound materials is gaining attention, as it can not only result in a better constructed product but also provide the engineering properties critical for better understanding of the connection between pavement design and long-term pavement performance. Moisture content is one of the main factors influencing soil modulus and should also be performed concurrent with field modulus measurement. However, existing LWDs do not have the function to measure moisture content. In this study, a national survey on acceptance of LWD and a substantial literature review were firstly carried out to study the current status of LWD application. Then, four types of representative soils from two projects provided by MoDOT were selected to investigate the implementation of LWD for construction acceptance of unbound materials. Four LWD devices including three Zorn ZFG 2000 and one Zorn ZFG lab 3.0, were used in laboratory and field tests. Furthermore, two moisture content analyzers including Aggrameter and Ohaus MB120 were chosen to evaluate their practicability of quick moisture content measurement in the field. Based on the results of considerable laboratory and field tests, it was concluded that the modulus-based construction quality assessment method using LWD and moisture content analyzer Ohaus MB120 worked well at four construction sites. In addition, a guideline was created for the use of the modulus-based method in the appendix"--Abstract.

Author: Harold L. Von Quintus
Publisher: Transportation Research Board
ISBN: 0309117771
Category : Nondestructive testing
Languages : en
Pages : 123

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Book Description
At head of title: National Cooperative Highway Research Program

Author: Leslie Struble
Publisher: Springer
ISBN: 3319616331
Category : Science
Languages : en
Pages : 366

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Book Description
This volume includes a unique group of chapters focusing on new advances in materials for infrastructure sustainability. Chapters have been well-organized and handled by a group of international experts in order to discuss a timely topic with regards to the sustainable infrastructures. This volume is part of the proceedings of the 1st GeoMEast International Congress and Exhibition on Sustainable Civil Infrastructures, Egypt 2017.

Author: Andreas Loizos
Publisher: CRC Press
ISBN: 1351585789
Category : Technology & Engineering
Languages : en
Pages : 3209

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Book Description
Bearing Capacity of Roads, Railways and Airfields includes the contributions to the 10th International Conference on the Bearing Capacity of Roads, Railways and Airfields (BCRRA 2017, 28-30 June 2017, Athens, Greece). The papers cover aspects related to materials, laboratory testing, design, construction, maintenance and management systems of transport infrastructure, and focus on roads, railways and airfields. Additional aspects that concern new materials and characterization, alternative rehabilitation techniques, technological advances as well as pavement and railway track substructure sustainability are included. The contributions discuss new concepts and innovative solutions, and are concentrated but not limited on the following topics: · Unbound aggregate materials and soil properties · Bound materials characteritics, mechanical properties and testing · Effect of traffic loading · In-situ measurements techniques and monitoring · Structural evaluation · Pavement serviceability condition · Rehabilitation and maintenance issues · Geophysical assessment · Stabilization and reinforcement · Performance modeling · Environmental challenges · Life cycle assessment and sustainability Bearing Capacity of Roads, Railways and Airfields is essential reading for academics and professionals involved or interested in transport infrastructure systems, in particular roads, railways and airfields.

Author: Anand J. Puppala
Publisher: Transportation Research Board
ISBN: 0309098114
Category : Technology & Engineering
Languages : en
Pages : 139

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Book Description
At head of title: National Cooperative Highway Research Program.

Author: W. Griffin Sullivan
Publisher:
ISBN:
Category :
Languages : en
Pages : 204

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Book Description
Cement stabilized material used for subbase or base pavement layers has been a widely accepted practice by many state Departments of Transportation (DOTs); particularly, for DOTs with limited access to quality crushed aggregates for pavement construction. Despite over 100 years of use, construction specifications governing cement stabilized pavement layers have largely remained the same and are primarily method based specifications (i.e. individual components evaluated and construction methods prescribed) rather than evaluating or testing mechanical properties of the end product. With the recent emergence of the Plastic Mold compaction Device (PM Device), multiple agencies are looking to depart from method based soil-cement specifications by implementing the PM Device for design and construction quality control and quality assurance (QC/QA) testing. Prior to this dissertation, PM Device protocols have been validated under lab conditions but only limited field validation had been performed. Additionally, time delay between initial mixing and compaction of cement stabilized soils is a known issue, which can affect compaction of PM Device specimens as well as construction target density values determined through AASHTO T134 Proctor testing. The main objectives of this dissertation are to investigate time delay effects on cement stabilized soil compactability during Proctor testing, develop a nationally recognized Standard Practice for PM Device specimen fabrication, and perform PM Device field evaluations for QC/QA testing. Lab experiments were conducted to investigate time delay effects and finalize PM Device Standard Practice protocols. Five field projects were evaluated to validate PM Device QC/QA applications and Standard Practice protocols in a construction environment. Time delay was observed to have a notable detrimental influence on compactability during AASHTO T134 Proctor testing and PM Device specimen fabrication. Recommended guidance was provided to characterize compaction delay effects. AASHTO PP92-19 was developed and published by AASHTO's Committee on Materials and Pavements to standardize specimen fabrication for the 3x6 inch and 4x8 inch versions of the PM Device. The PM Device fared well for construction activities when benchmarked relative to density, strength, and modulus of cores taken from constructed cement stabilized pavement layers. The PM Device was recommended for implementation consideration by state DOTs and other agencies.

Author: E. Tutumluer
Publisher:
ISBN:
Category : Aggregates (Building materials)
Languages : en
Pages : 180

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Book Description
"TRB's National Cooperative Highway Research Program (NCHRP) Synthesis 445: Practices for Unbound Aggregate Pavement Layers consolidates information on the state-of-the-art and state-of-the-practice of designing and constructing unbound aggregate pavement layers. The report summarizes effective practices related to material selection, design, and construction of unbound aggregate layers to potentially improve pavement performance and longevity."--Publisher website.

Author: Soheil Nazarian
Publisher:
ISBN:
Category : Pavements
Languages : en
Pages : 17

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Book Description
"TRB's National Cooperative Highway Research Program (NCHRP) Research Results Digest 391: Modulus-Based Construction Specification for Compaction of Earthwork and Unbound Aggregate develops a modulus-based construction specification for acceptance of compacted geomaterials." -- publisher's description

Author:
Publisher:
ISBN:
Category : Pavements
Languages : en
Pages : 178

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Book Description