Infrastructure is essential for commerce. Planners and stakeholders want to develop infrastructure that is resilient to both chronic (e.g., material degradation) and episodic (e.g., earthquake) hazards. Accuracy in service life prediction remains elusive, particularly when episodic events are experienced in an aging structure that might no longer have the designed properties. This Program will develop and deploy measurement science to promote resilient infrastructure with a focus on materials properties by
This project would enable stakeholders to better manage US infrastructure assets through improved assessment of existing infrastructure and science-informed selection of materials for more resilient infrastructure.
Objective - To develop and deploy measurement science to reliably assess the current and future performance of engineered materials in support of resilient infrastructure given exposure to chronic (e.g., materials degradation) and episodic (e.g., earthquakes) hazards.
What is the technical idea?
To ensure that materials perform as needed for the expected service life of infrastructure, knowledge and prediction of the service life of the materials are necessary. Today, the selection of materials for new construction and the estimate of the remaining service life of materials already in place is left to the engineer and the inspector, respectively. The technical idea is to enable solutions to these two needs that would ensure a resilient infrastructure:
To maintain resilience, it is necessary to build or repair infrastructure with the appropriate materials to achieve the desired level of performance for the anticipated hazards for the planned service life. Thus, tools are needed to ensure that the selection of materials is done using science-based predictive methodologies that forecast the performance of materials under actual operating conditions both in new construction and in repair. NIST will develop tools and methodologies to predict the performance of materials, starting with concrete and polymeric materials, needed for new construction and for repair.
To have a resilient community, it is necessary that the infrastructure is operational at all times. Operational infrastructure implies that all the parts of a structure (from roads to schools, hospitals, power/energy generation & distribution, communication) operates as designed. Thus, tools and methodologies are needed to assess an existing structure’s current state or level of performance. NIST will develop tools and methodologies to assess the performance of materials used in an existing structure and predict its remaining service life.
These two thrusts will enable prediction of service life of infrastructure. It will allow development of tools for engineers, inspectors, and owners to make decisions on materials based on an accurate projection of the time and exposure dependent conditions of the structure.
If the information is known for each material in a structure, the next stage would be to determine the status of the entire structure by combining all the material service curves for the structure and working directly with the NIST Engineering Laboratory Resilience Programs to conduct validation studies. It could be assumed that the structure would fail (no longer functional) if the most critical component fails or is sufficiently deteriorated. This information could then be integrated with other programs in the resilience goal to ensure that models have the materials parameters needed to inform a community for planning resilience.
What is the research plan?
Traditionally, this program has limited its research to two materials, concrete and polymers. To better address the resilience of structures, this program will develop a strategic plan that identifies the most important measurement science challenges for achieving resilient buildings and infrastructure by material selection and assessment for all infrastructure materials, such as concrete, steel, wood, ceramics, and polymers, as it applies to the leading chronic and episodic hazards. It will also pursue activities that would enhance the capabilities for research on any material, including those listed below in five projects.
Once the strategic plan is completed, all resources are to be directed towards the resilience measurement science challenges identified in the strategic plan. The goal is to ensure development of tools for the industry to address two main thrusts: Material Selection and Material Assessment.
The projects objectives are listed here as per the two thrusts:
Outputs from the projects will go into a materials database, comparable to the MML Materials Data Curation System framework, and will consist of materials properties as a function of a variety of environmental stressors or other variables so that stakeholders can use the data to develop predictive models for their products. NIST will collaborate closely with the industry to ensure that any tools developed will be quickly adopted as standards.