基于脱脂奶粉联合诱导碳酸钙沉淀技术的古建筑修复加固

Restoration and reinforcement of ancient buildings based on the combined induced calcium carbonate precipitation technology of skimmed milk powder

为研究诱导碳酸钙技术修复与加固砖石古建筑的效果,采用胶结液中添加脱脂奶粉的方法对微生物诱导碳酸钙沉淀(microbially induced carbonate precipitation,MICP)技术和酶诱导碳酸钙沉淀(enzyme induced carbonate precipitation,EICP)技术进行改良,对比分析碳酸钙的沉淀质量、X射线衍射(X-ray diffraction,XRD)下的晶型、扫描电子显微镜(scanning electron microscope,SEM)下的晶貌及砖石抗折强度的修复效果。结果表明:EICP生成碳酸钙沉淀质量最多;脱脂奶粉作为添加剂,能够改变MICP的碳酸钙晶型,使原有8.3%球霰石的沉淀完全转化为方解石沉淀;通过抗折试验得到MICP技术能修复与加固古建筑砖石,特别是在添加脱脂奶粉后,其抗折强度能达到原有砖石抗折强度的121.69%。因此,添加脱脂奶粉的MICP技术更适用于砖石古建筑的修复与加固。

Microbially induced carbonate precipitation(MICP)technology and enzyme induced carbonate precipitation(EICP)technology were improved by adding skimmed milk powder into the cementing solution to repair and strengthen the ancient masonry buildings with induced calcium carbonate technology.The precipitation quality of calcium carbonate,crystal shape under X-ray diffraction(XRD),crystal appearance under scanning electron microscope(SEM)and restoration effect of brick and stone fracture strength were compared and analyzed.The results show that the quality of calcium carbonate precipitation generated by EICP is the highest.As an additive,skimmed milk powder can change the calcium carbonate crystal shape of MICP and completely convert the original 8.3%aragonite precipitation into calcite precipitation.The MICP technology can repair and reinforce ancient architectural bricks and stones through folding resistance test.Especially after adding skimmed milk powder,it reached 121.69%of the original brick and stone folding strength.Therefore,MICP technology,as an additive of skimmed milk powder,is more suitable for the restoration and reinforcement of brick and stone ancient buildings.