Advanced cementitious materials, commonly referred to as ultra-high performance concretes (UHPCs), are developing rapidly and show promise for civil infrastructure and protective construction applications. Structures exposed to blasts experience strain rates on the order of 102 s-1 or more. While a great deal of research has been published on the durability and the static properties of UHPC, there is less information on its dynamic properties. The purpose of this report is to (1) compile existing dynamic property data—including compressive strength, tensile strength, elastic modulus, and energy absorption—for six proprietary and research UHPCs and (2) implement a single-degree-of-freedom (SDOF) model for axisymmetric UHPC panels under blast loading as a means of comparing the UHPCs. Although simplified, the model allows identification of key material properties and promising materials for physical testing. Model results indicate that tensile strength has the greatest effect on panel deflection, with unit weight and elastic modulus having a moderate effect. CEMTECmultiscale® deflected least in the simulation. Lafarge Ductal®, a commonly available UHPC in North America, performed in the middle of the five UHPCs considered.

In August of 2021, unexpected cracking was discovered in the concrete of newly constructed apartment towers and parking garages at Camp Walker, Daegu, South Korea. Initial evaluation by U.S. Army Corps of Engineers Far East District (USACE-POF) determined the towers to be safe for continued occupation. Out of an abundance of caution a team from the Engineer Research and Development Center (ERDC) conducted an independent evaluation of these structures to further verify life safety. Additionally, this evaluation sought to determine the potential causes of this cracking and remediation schemes both to inform future construction, but also to lay the groundwork for a more in-depth lifecycle evaluation by an Architectural/Engineering (AE) firm specializing in structural forensics. The ERDC evaluation consisted of on-site inspection, non-destructive testing, materials sampling and testing, and review of particular design and construction documentation provided by the Far East District. The results of the evaluation confirmed the Far East District’s findings that there was not a threat to life safety in these structures. Furthermore, the results of the ERDC evaluation indicated that drying shrinkage was the most likely causes of the observed cracking. In the areas where this cracking was the most severe, repair with epoxy injection was recommended for continued structural safety. In areas with moderate cracking, sealing of cracks was recommended to prevent long-term durability issues decreasing the lifespan of the structures.