Mechanical response of textile-reinforced aerated concrete sandwich panels was investigated using instrumented three-point bending tests under quasi-static and low-velocity impact loads. Two types of core material were compared in the sandwich composite consisting of plain autoclaved aerated concrete (AAC) and fiber-reinforced aerated concrete (FRAC), and the stress skins were alkali-resistant glass (ARG) and textile reinforced concrete (TRC). The textile-reinforced layer promoted distributed cracking mechanisms and resulted in significant improvement in the flexural strength and ductility. Digital Image Correlation (DIC) was used to study the distributed cracking mechanism and obtain impact force-crack width response at different drop heights. A constitutive material model was also developed based on a multi-linear tension/compression strain hardening model for the stress-skin and an elastic, perfectly plastic compression model for the core. A detailed parametric study was used to address the effect of model parameters on the flexural response. The model was further applied to simulate the experimental flexural data from the static and impact tests on the plain aerated concrete and sandwich composite beams.

A paradigm shift is required in the design of sustainable structures utilizing UHPC. Using a combination of new materials formulations and closed-form analysis procedures to calculate the load-deflection response of a structure, limit-state designs aimed at the long-term durability of UHPC cement composite systems are proposed. The perspective is to meet the traditional ultimate design criteria and emphasize the perspective on serviceability measures defined in terms of durability, deflection, stiffness, and performance aspects under the service loads. Three main stages of sustainable product development will be addressed using the material properties of nonproprietary UHPC. The influence of fiber type, matrix modifications, and processing parameters under tensile and flexural loading are incorporated in constitutive material properties. The enhanced tensile behavior in the post-cracking stage is primarily governed by mechanical anchorage and bond characteristics between matrix and fibers. The residual strength under flexural loads, allows for the distribution of localization and results in additional cracking. The significant delays in stiffness loss and damage localization allows for deflection hardening applications. Innovative methods of design using combinations of reinforcement and UHPC materials are presented.