含铝酸钙水泥(CAC)的耐火材料因其优异的机械抗性而常用于冶金和石化行业,即使在超过1000°C的温度下,并且不需要额外的加固。这项研究旨在通过开发超高性能结构来促进这种实践,这些结构可以提供建筑物的防火和防爆保护。这种结构需要钢筋以承受意外的拉应力,债券的性能变得至关重要。然而,这些材料的抗压强度可能与它们在高温条件下的抗粘结性无关。这项研究调查了带肋不锈钢奥氏体钢筋在结构工程典型耐火材料中的粘结性能。该分析考虑了三种基于古铜色的成分,即,具有25重量%CAC的常规浇注料(CC),含12重量%CAC的中等水泥浇注料(MCC),低水泥浇注料(LCC),和低水泥铝土矿基浇注料(LCB);LCC和LCB浇注料含有7wt%的CAC。前三种耐火组合物被设计成实现100MPa的冷抗压强度(CCS)。而LCB混合比例设定为达到150MPa的CCS。在400°C处理后进行机械和拔出测试,600°C,800°C,和1000°C;参考样品不进行额外的温度处理。本研究使用X射线荧光(XRF),X射线衍射(XRD)和扫描电子显微镜(SEM)方法来捕获材料的变化。测试结果表明,粘接电阻,以拉出变形能表示,与抗压强度没有直接关系,支持研究假设。
Refractory materials containing calcium aluminate cement (CAC) are commonly used in the metallurgical and petrochemical industries due to their exceptional mechanical resistance, even at temperatures exceeding 1000 °C, and do not require additional reinforcement. This study seeks to advance this practice by developing ultra-high-performance structures that offer building protection against fire and explosions. Such structures require bar reinforcement to withstand accidental tension stresses, and the bond performance becomes crucial. However, the compressive strength of these materials may not correlate with their bond resistance under high-temperature conditions. This study investigates the bond behavior of ribbed stainless austenitic steel bars in refractory materials typical for structural projects. The analysis considers three chamotte-based compositions, i.e., a conventional castable (CC) with 25 wt% CAC, a medium-cement castable (MCC) with 12 wt% CAC, a low-cement castable (LCC), and a low-cement bauxite-based castable (LCB); the LCC and LCB castables contain 7 wt% CAC. The first three refractory compositions were designed to achieve a cold compressive strength (CCS) of 100 MPa, while the LCB mix proportions were set to reach a CCS of 150 MPa. Mechanical and pull-out tests were conducted after treatment at 400 °C, 600 °C, 800 °C, and 1000 °C; reference specimens were not subjected to additional temperature treatment. This study used X-ray fluorescence (XRF), X-ray diffraction (XRD), and scanning electron microscopy (SEM) methods to capture the material alterations. The test results indicated that the bonding resistance, expressed in terms of the pull-out deformation energy, did not directly correlate with the compressive strength, supporting the research hypothesis.