Study on the Mechanical Properties and Durability of Hydraulic Lime Mortars Based on Limestone and Potassium Feldspar

Natural hydraulic lime (NHL) can be used as an inorganic cementitious material, it exhibits low shrinkage, salt-alkali resistance, moderate strength, and good durability with cultural relics. There has been increasing interest in NHL, is considered appropriate material for the restoration reinforcement of architectural In this study, limestone potassium feldspar were mixed calcined at different ratios high temperatures, artificial (HL) was produced. According to X-ray diffraction (XRD) results, resulting products after high-temperature calcination mainly composed calcium oxide, dicalcium silicate (C2S), aluminosilicate (C2AS). As a compromise, when accounted 30% total mass, HL contains more suitable air-hardening component component. Scanning electron microscope (SEM) Energy Dispersive Spectrometer (EDS) analyses show that phases carbonate (CaCO3) hydrated (C-S-H) gradually increased prolonged curing time HL. To study partial mechanical properties HL, comparison made NHL. The investigated flexural compressive strengths shrinkage. results higher strength than but NHL smaller Accelerated aging tests indicated NHL5 led resistance water immersion, fluctuations temperature humidity, sulphate decay, alkali environment, frost–thaw action NHL2. excellent conservation stone relics future.