摘要
采用了四点抗弯试验和斜剪试验两种方法,并通过改变磷酸钾镁水泥(MKPC)净浆的矿物成分,研究了MKPC净浆与硅酸盐混凝土的粘结强度,同时本试验还测定了MKPC净浆的抗压强度及收缩变形,最后通过SEM对微观结构进行分析,阐明了粘结机理。试验结果表明:加入矿物掺合料可以有效提高MKPC净浆的粘结强度、抗压强度和体积稳定性。单掺10%偏高岭土的试件,其28 d粘结强度最高,单掺20%偏高岭土次之;与单掺偏高岭土的试件相比,双掺10%偏高岭土和10%粉煤灰则会使试件的28 d粘结强度有所降低,但高于空白组的28 d粘结强度;单掺10%或20%偏高岭土分别使MKPC净浆的28 d抗压强度提高了5. 91%和11. 94%,双掺粉煤灰和偏高岭土的MKPC净浆,其28 d抗压强度高达72. 9 MPa,比同龄期空白组试件提高了16. 55%;掺入偏高岭土和粉煤灰会使MKPC净浆早期微膨胀,后期收缩趋势放缓。
The bond strength between MKPC paste and silicate concrete was studied by means of four-point bending test and inclined shear test and by changing the mineral composition of potassium magnesium phosphate cement paste.At the same time,the compressive strength and shrinkage deformation of MKPC paste were measured.Finally,the microstmcture was analyzed by SEM,and the bond mechanism was clarified.The test results show that mineral admixtures can effectively improve the bond strength,compressive strength and volume stability of potassium magnesium phosphate cement paste.The 28 d bond strength of the specimens with only 10%metakaolin is the highest,followed by the addition of 20%metakaolin.Compared with the specimens only mixed with metakaolin,the 28 d bond strength of the specimens mixed with 10%metakaolin and 10%fly ash decreases,but higher than that of the blank group.The addition of 10%or 20%metakaolin alone increases the 28 d compressive strength of MKPC paste by 5.91%and 11.94%respectively.The 28 d compressive strength of MKPC paste mixed with fly ash and metakaolin is 72.9 MPa,which is 16.55%higher than that of blank group at the same age.Incorporation of metakaolin and fly ash can make MKPC paste expand early and slow down later.
作者
傅新雨
杨建明
单春明
陶涛
FU Xin-yu;YANG Jian-ming;SHAN Chun-ming;TAO Tao(Fuculty of Civil Engineering and Mechanics,Jiangsu University,Zhenjiang 212013,China;Department of Civil Engineering,Yancheng Institute of Technology,Yancheng 224051,China)
出处
《硅酸盐通报》
CAS
北大核心
2019年第7期2242-2249,共8页
Bulletin of the Chinese Ceramic Society
基金
国家自然科学基金(51578475)
江苏省高等学校自然科学研究面上项目(17KJB560012)
关键词
磷酸钾镁水泥
粉煤灰
偏高岭土
粘结强度
抗压强度
potassium magnesium phosphate cement
fly ash
metakaolin
bond strength
compressive strength
