古建水硬性石灰材料的制备与耐久性能

Preparation and Durability of Hydraulic Lime Used as Repairing Materials for Architectural Heritage

以气硬性石灰、白水泥、活性微粉、添加剂、纤维等为主要原料,设计制备了水硬性石灰砂浆作为古建修补材料;探究了加速碳化对水硬性石灰砂浆力学强度发展的影响,并以相对动弹性模量、质量损失率为主要评价指标,系统研究了水硬性石灰砂浆在单一因素(冻融、硫酸盐)与多因素耦合(干湿循环-硫酸盐)作用下的耐久性能.结果表明:加速碳化能显著提高水硬性石灰砂浆的力学强度,传统石灰砂浆加速碳化3d的抗压强度是自然养护条件下的7.5倍;掺加质量分数为0.1%的聚丙烯纤维能显著提高水硬性石灰砂浆的抗冻性,经历116次冻融循环后水硬性石灰砂浆未出现明显的冻融破坏;掺加质量分数为1%的铝制外加剂能明显改善水硬性石灰砂浆的抗硫酸盐侵蚀性能.

A novel hydraulic lime was prepared as repairing materials for architectural heritage using airhardetaittg lime,white cement,reactive powders,additives and fiber as the main material.The effect of accelerated carbonation on the mechanical properties and the durability of hydraulic lime mortar were investigated.The modulus of elasticity and the mass loss were the main evaluation indicators in univariate（freeze-thaw cycle,sulfate）and multivariate coupling（dry-wet cycle and sulfate）conditions.Results show that strength of hydraulic lime mortar after 3 dof accelerated carbonation is 7.5 times that under the natural curing conditions.The frost resistance of hydraulic lime mortars is significantly improved by adding0.1%（by mass）polypropylene fibers and no visual damage occurred to the mortar after 116 freeze-thaw cycles.Additionally,the resistance to sulfate attack of hydraulic lime mortar is also greatly improved by adding 1%（by mass）aluminum additives.