Thermal curing of fibre-reinforced UHPC

在本课题框架内，系统地研究了固化对纤维增强UHPC性能的影响。除了目前常用的90°C热处理外，还将应用温度明显更高的热固化和热压固化（高压灭菌）。因此，在正常硬化条件下反应性较低或几乎不反应的起始材料将被大大活化，在很大程度上影响微观结构，从而影响材料的性能。研究的目标是通过控制固化条件（温度、压力和持续时间）来改善UHPC的性能。为了实现这一目标，有必要获得热处理和高压灭菌胶凝系统中相的形成和稳定性的基本知识。为此，相组合的变化主要取决于不同的固化条件，并考虑纤维结合，评估其对UHPC力学性能的影响。

In the frame of the proposed research project the influence of curing on the properties of fibre-reinforced UHPC is to be investigated systematically. Besides the heat treatment at 90°C commonly used today, heat curing and heat-pressure curing (autoclaving) at significantly higher temperatures will be applied. Thus, starting materials, which are less or barely reactive under normal hardening conditions, will be activated considerably, influencing to a great extent the micro structure and consequently the performance of the material. The goal of the investigations is improve the properties of UHPC by controlling the curing conditions (temperature, pressure and duration). In order to attain this goal it is necessary to obtain fundamental knowledge of the formation and the stability of the phases in the heat treated and autoclaved cementitious system. For this purpose the phase assemblage is varied mainly by application of different curing conditions and its influence on the mechanical properties of the UHPC is evaluated considering the fibre bond.