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OUSD (R&E) CRITICAL TECHNOLOGY AREA(S): Advanced Materials OBJECTIVE: DTRA seeks technologies that demonstrate capabilities to detect, identify, and differentiate high performance concrete (HPC) and ultra-high performance concrete (UHPC). Ideal systems will provide the end user with a portable, lightweight system that can detect high performance concrete from a large standoff distance. In addition, it is desired for these systems to have the ability to detect flaws and vulnerable areas within concrete structures. The technologies employed to provide advancements in these capabilities may include, but not limited to ultrasonic pulse velocity (UPV), pulsed fiber lasers, laser induced plasma shockwave generation, acoustic technologies, laser-based ultrasonic testing, laser scanning technologies (ex. LiDAR), and laser-induced breakdown spectroscopy (LIBS). The purpose of these technologies is to detect high/ultra performing concrete by assessing the concrete surface, thickness, material property assessment, surface composition, and foundational crack detection. The concrete detection technologies should be able to assess and diagnose high and ultra performance concrete within a short period of time. The end user requires the ability to assess the foundational structures for evidence of HPC or UHPC. DESCRIPTION: HPC and UHPC offer enhanced performance compared to regular conventional concrete. They both offer higher strength levels, durability and resistance to environmental conditions, low porosity and permeability, enhanced ductility and can be tailored to specific project designs. These characteristics make them favored for high value targets, and their presence may be an important indicator for warfighters regarding structures of interest. The envisioned capability would allow for ground forces or drones to diagnose contrete to aid in creating targeting packages for the best selection of the sometimes limited and highly expensive warheads/weapons to be used. HPC and UHPC are both advanced types of concrete designed to exhibit superior strength, however, HPC and UHPC have distinct differences. UHPC typical has a much higher compressive and flexural strength compared to HPC. UHPC can achieve compressive strengths exceeding 21,000 psi (145 MPa), while HPC typically ranges from 6,000 to 12,000 psi (41 to 83 MPa). Similarly, UHPC exhibits higher flexural strength, often exceeding 3,000 psi (20 MPa), whereas HPC typically ranges from 500 to 1,500 psi (3.5 to 10 MPa). HPC and UHPC’s both utilize very fine powders like silica fume and have an extremely low water to cement ratio. UHPC’s may often also incorporate steel or synthetic fibers to enhance toughness and ductility. HPC tends to have lower costs for materials and is more readily available and easier to produce. UHPC requires specialized equipment and expertise to ensure the mixing, casting, and curing fits the project needs. PHASE I: PHASE I: Conceptual Design Phase I will result in a final report assessing current capabilities, comparing the technologies results and listing the most promising technologies and methods to provide the capability. Demonstrate the ability to create a device with the technologies to enable the end user to detect HPC and UHPC. Develop initial concept design and model key elements of various technologies that can be utilized within these devices. These devices should be able to identify and differentiate between HPC and UHPC, while assessing the vulnerability of concrete formations at varying distances. Develop and demonstrate prototypes that fit the listed requirements. Phase I close out requires key component technological milestones for at least two prototypes. PHASE II: PHASE II: Prototype Development Based on Phase I modeling and design, Phase II begins with prototype development. Construct and demonstrate the basic capabilities of the technology. Initial prototypes should at a minimum have an effective standoff distance of 30 feet with 5 feet variability. Complete hardware and software development and begin limited basic field-testing objectives; demonstrate the prototypes and their capabilities. Phase II should include an evaluation of the prototype in a realistic environment. PHASE III DUAL USE APPLICATIONS: PHASE III: Test and Selection Once the prototypes are developed and have demonstrated success in HPC/UHPC detection, further testing of the equipment should be conducted against various other technologies and results should be compared. Assess the ability of the devices selected to differentiate between HPC and UHPC in addition to assessing concrete foundational vulnerabilities. Testing priorities: 1. Accuracy in HPC and UHPC detection; 2. Effective standoff distance (1000ft); 3. Detecting vulnerabilities and foundational weaknesses within concrete structures. Phase III will be completed once a suitable technological device with the desired is selected. All data collected during the testing and demonstration events of the final chosen system will be included in the final report along with a user’s manual. REFERENCES: 1. High-performance concrete. High-Performance Concrete - an overview | ScienceDirect Topics. (n.d.).https://www.sciencedirect.com/topics/engineering/high-performance-concrete; 2. Wakata, S., Hosoya, N., Hasegawa, N., & Nishikino, M. (2022). Defect detection of concrete in infrastructure based on Rayleigh wave propagation generated by laser-induced plasma shock waves. International Journal of Mechanical Sciences, 218, 107039.https://doi.org/10.1016/j.ijmecsci.2021.107039.; 3. Ultra-high performance concrete. Ultra-High Performance Concrete | FHWA. (n.d.).https://highways.dot.gov/research/structures/ultra-high-performance-concrete/ultra-high-performance-concrete.; KEYWORDS: High performance concrete; sensor; WMD facilities; laser; targeting; ultrasonic pulse velocity (UPV); ultra-high performance concrete