Construction

Self-Consolidating Concrete for Cast-in-Place Bridge Components

TRB recorded a series of videos in February 2017 that featured research from National Cooperative Highway Research Program (NCHRP) Report 819: Self-Consolidating Concrete for Cast-in-Place Bridge Components. The report presents recommended guidelines for the use of self-consolidating concrete (SCC) in cast-in-place highway bridge components. These guidelines address the selection of constituent materials, proportioning of concrete mixtures, testing methods, fresh and hardened concrete properties, production and quality control issues, and other aspects of SCC. The videos discuss the research scope and approach, small-scale lab-mixed concrete specimens, full-scale ready-mixed concrete specimens, and proposed changes to the AASHTO Load and Resistance Factor Design (LRFD) Bridge Design and Construction Specifications. The videos are available on-demand at no cost.

The slides are available.

Selecting and Specifying Concrete Surface Preparation for Sealers, Coatings, Polymer Overlays, and Concrete Repair

This guide provides owners, designers, specifiers, contractors, and manufacturers with the tools needed to select and specify the methods for preparing concrete surfaces prior to the application of a protective system or repair material. Surface preparation is the process by which a sound, clean, and suitably roughened surface is produced on a concrete substrate. Surface preparation includes the removal of laitance, dirt, oil, films, paint, coatings, sound and unsound concrete, and other
materials that will interfere with the adhesion or penetration of a sealer, coating, polymer overlay, or repair material. Proper surface preparation will open the pore structure of the concrete substrate and establish profiles suitable for the application of the specified protective system or repair material.

Download the Guide (.pdf)

Construction Procedures and Specifications for Bonded Repair and Retrofit of Concrete Structures using FRP Composites

Construction Procedures and Specifications for Bonded Repair and Retrofit of Concrete Structures using FRP Composites is designed to assist State Department of Transportation (DOT) construction and maintenance operation staff develop knowledge of project requirements of FRP repairs, substrate surface preparation methods, and procedures and steps for installation of FRP systems.

Topics covered in this course include:

• • Specifications, including scope, definitions, tolerances, and site considerations
  • Submittal requirements, including working drawings and quality control/quality assurance plans
  • Storage, handling, and disposal requirements, including shelf life, safety hazards, personnel and work place protection, and clean up
  • Various aspects of substrate repairs and surface preparation of concrete structures
  • Use of externally-bonded and near-surface mounted FRP systems for repairs
  • Procedures and steps for installation of externally bonded FRP systems
  • Procedures and steps for installation of near-surface mounted FRP systems
  • Environmental considerations for FRP installation
  • Identification of defects and appropriate solutions of FRP applications

The success of repairs and retrofit of concrete structures using FRP Composite is dependent on State Department of Transportation (DOT) construction personnel taking an active role in ensuring construction procedures and specifications are adhered to. Hence, knowledge of proper construction procedures and specifications for FRP projects is necessary to control quality of work.

Register for the Web-based Training

FHWA Post-Tensioning Installation and Grouting Manual

FHWA recently completed updating the Post-Tensioning Installation and Grouting Manual.  This manual has been a valuable and frequently referenced resource for the bridge community and the updated manual has incorporated many recent changes in the post-tensioning state-of-practice, including new post-tensioning components, new testing procedures, and detailing criteria for longer service life- protection levels.

Download the Manual (.pdf)