干挂饰面石材抗冻性能试验研究

EXPERIMENTAL RESEARCH ON FROST RESISTANCE OF DRY HANGING FACING STONE

以目前石材幕墙工程中常用的天然干挂饰面石材为代表,通过试验研究不相同吸水率下的花岗岩、石灰石以及砂岩经过不同的防护处理后,在冻融循环作用下压缩强度以及弯曲强度的变化。试验结果表明进行防护处理可以提升石材的抗冻性能。同时通过开展不同次数的冻融循环试验,对这三类石材的抗冻系数随着冻融循环次数的变化进行对比和分析,绘出了抗冻系数与冻融次数的拟合关系曲线,得到了抗冻系数随冻融循环次数的衰减规律并预测了这三类常用石材冻融破坏的最少冻融次数。

Taking the natural dry hanging stone which has been commonly used in stone curtain wall engineering as an example,under freeze-thaw cydes,the changes of compressive strength and flexural strength of granite,limestone and sandstone with different water absorption and protective treatments were studied through tests,the test results showed that the protective treatment could promote the frost resistance of the stone. By conducting different numbers of freeze-thaw cycling test at the same time,the frost resistance coefficients of three kinds of stones as the change of freeze-thaw cycles was compared and analyzed,the fitting curves of frost resistance coefficient and the number of freezing and thawing cycles were obtained,the attenuation law of frost resistance coefficient with the number of freezethaw cycles was obtained and the minimum number of freeze-thaw cycles of three kinds of commonly-used stones occurred damage was predicted.