Precision Estimates Of Aashto T 201 Aashto T 202 And Aasto

TRB's National Cooperative Highway Research Program (NCHRP) Research Results Digest 350: Continuing Project to Synthesize Information on Highway Problems is a digest of the progress and status of NCHRP Project 20-5, "Synthesis of Information Related to Highway Problems."

"This digest summarizes key findings obtained in 2009 and 2010 from continuing NCHRP Project 9-26A, "Data Mining and Interlaboratory Studies to Prepare Precision Statements for AASHTO Standard Test Methods." Project 9-26A was conducted by the AASHTO Materials Reference Laboratory under the direction of the principal investigator, Haleh Azari. This digest is based on the contractor's task reports, which are available online as NCHRP Web-Only Documents 163 through 166."

Design related project level pavement management - Economic evaluation of alternative pavement design strategies - Reliability / - Pavement design procedures for new construction or reconstruction : Design requirements - Highway pavement structural design - Low-volume road design / - Pavement design procedures for rehabilitation of existing pavements : Rehabilitation concepts - Guides for field data collection - Rehabilitation methods other than overlay - Rehabilitation methods with overlays / - Mechanistic-empirical design procedures.

For courses in Civil Engineering Materials, Construction Materials, and Construction Methods and Materials offered in Civil, Environmental, or Construction engineering departments. This introduction gives students a basic understanding of the material selection process and the behavior of materials — a fundamental requirement for all civil and construction engineers performing design, construction, and maintenance. The authors cover the various materials used by civil and construction engineers in one useful reference, limiting the vast amount of information available to the introductory level, concentrating on current practices, and extracting information that is relevant to the general education of civil and construction engineers. A large number of experiments, figures, sample problems, test methods, and homework problems gives students opportunity for practice and review.

Integral abutment (IA) construction has become the preferred method over conventional construction for use with typical highway bridges. However, the use of these structures is limited due to state mandated length and skew limitations. To expand their applicability, studies were implemented to define limitations supported by rational analysis rather than simply engineering judgment. Previous research investigations have resulted in larger length limits and an overall better understanding of these structures. However, questions still remain regarding IA behavior; specifically questions regarding long-term behavior and effects of skew. To better define the behavior of these structures, a study was implemented to specifically investigate the long term behavior of IA bridges. First, a field monitoring program was implemented to observe and understand the in-service behavior of three integral abutment bridges. The results of the field investigation were used to develop and calibrate analytical models that adequately capture the long-term behavior. Second, a single-span, quarter-scale integral abutment bridge was constructed and tested to provide insight on the behavior of highly skewed structures. From the acquired knowledge from both the field and laboratory investigations, a parametric analysis was conducted to characterize the effects of a broad range of parameters on the behavior of integral abutment bridges. This study develops an improved understanding of the overall behavior of IA bridges. Based on the results of this study, modified length and skew limitations for integral abutment bridge are proposed. In addition, modeling recommendations and guidelines have been developed to aid designers and facilitate the increased use of integral abutment bridges.