Anchorage Design and Detailing for Fabric-Reinforced Cementitious Matrix Retrofits of Transportation Concrete Structures
The repair and rehabilitation of transportation structures is urgently needed to restore structural capacity, slow deterioration caused by aging, overloading, and environmental stressors, and minimize disruptions associated with large-scale replacement projects. State DOTs and the Federal Highway Administration (FHWA) have implemented several advanced rehabilitation techniques, including fiber-reinforced polymer (FRP) composites, ultra-high-performance concrete, and fiber-reinforced cementitious matrix (FRCM) systems. FRCM consists of an open-grid textile made of FRP or steel strands embedded within an inorganic cementitious matrix. The system offers multiple advantages over traditional FRP, including mechanical compatibility with concrete and masonry substrates, improved fire and elevated-temperature performance, vapor permeability, durability in moist or cold environments, and ease of application in field conditions. As an externally bonded strengthening system, the performance of FRCM is governed by the ability of the FRCM–substrate interface to maintain composite action and to transfer forces effectively. Premature interfacial slip, end debonding, or localized interface damage are commonly reported for unanchored FRCM systems. These brittle failure modes often occur at loads far below the tensile capacity of the textile, limiting the effectiveness of the strengthening system to 30–60% of its potential and undermining both safety and return on investment. Introducing anchorage mechanisms into FRCM systems provides an engineered means to restrain interfacial slip, delay debonding, promote more favorable failure modes, and enable the textile to mobilize higher tensile strains. However, the existing literature on FRCM anchorage is sparse, fragmented, and lacking in unified, design-oriented guidance. Quantitative provisions addressing anchor geometry, capacity, and interaction with the primary FRCM reinforcement remain absent from current codes and standards. The primary objective of this research is to advance the understanding, design, and implementation of anchorage systems for FRCM-strengthened concrete members, with the goal of mitigating premature debonding and achieving ductile, and efficient strengthening outcomes. Specifically, the project aims to: (a) synthesize and critically evaluate the current state of knowledge on FRCM anchorage; (b) develop and experimentally validate practical anchorage systems including transverse wraps, mechanical anchors, and spike anchors; and (c) produce a design-oriented framework for selecting, proportioning, and detailing anchorage systems. Two coordinated experimental programs are proposed: (1) bond-level tests to characterize the effects of anchorage presence and type on joint force transfer, slip response, and failure mechanisms; and (2) flexural tests on reinforced concrete beams strengthened with anchored and unanchored FRCM reinforcement, to evaluate the translation of bond-level behavior to member-level performance and to verify design expressions under combined shear and normal stresses. The proposed research will equip state DOTs with validated anchorage solutions, support cost-effective preservation strategies, and accelerate the adoption of durable composite materials for extending the service life of transportation infrastructure.
Language
- English
Project
- Status: Active
- Funding: $136,582.00
-
Contract Numbers:
69A3552348308
-
Sponsor Organizations:
Office of the Assistant Secretary for Research and Technology
University Transportation Centers Program
Department of Transportation
Washington, DC United States 20590 -
Managing Organizations:
Center for Transformative Infrastructure Preservation and Sustainability
North Dakota State University
Fargo, North Dakota United States 58108-6050 -
Project Managers:
Tolliver, Denver
-
Performing Organizations:
Civil & Environmental Engineering
Brookings, SD United States -
Principal Investigators:
Jawdhari, Akram
- Start Date: 20260322
- Expected Completion Date: 20280321
- Actual Completion Date: 0
- USDOT Program: University Transportation Centers Program
- Source Data: CTIPS-072
Subject/Index Terms
- TRT Terms: Anchorages; Bonding; Cement; Concrete structures; Fiber reinforced materials; Flexural strength; Rehabilitation; Retrofitting
- Subject Areas: Bridges and other structures; Design; Highways; Maintenance and Preservation; Materials;
Filing Info
- Accession Number: 01985475
- Record Type: Research project
- Source Agency: Center for Transformative Infrastructure Preservation and Sustainability
- Contract Numbers: 69A3552348308
- Files: UTC, RIP
- Created Date: Apr 12 2026 11:52PM