Research on the Characteristics of Rapid-hardening and High-strength Grouting Mortar in Deep Foundation Pit
JIAO Wei-gang;DING Yan-jie;CHE Yu-long;GUO Yi-xian;YANG Yi;BGI Engineering Consultants LTD;School of Mechanics & Civil Engineering,China University of Mining & Technology;
In order to solve the problems that the hardening time is long and anchoring force is insufficient in deep foundation pit engineering,the traditional bolt grouting material with admixture was improved design,the rapid-hardening and high-strength grouting mortar was researched by intensity,shrinkage characteristics and microcharacteristic analysis. The results showed that ① the modification slurry intensity of 7 d was 23. 32 MPa,the intensity of 28 d was 28. 06 MPa,and it was 1. 434 times of the pure slurry with the same water cement ratio; ②the micro expansion characteristics of modified slurry was significant,the micro expansion rate was 0. 314%,and it was 1. 82 times of the pure slurry with the same water cement ratio; ③ the results of XRD test showed that the compressive strength of modified slurry was effected great by tricalcium silicate( M3) and brownmillerite,the strength was increased with the incorporation of alum,and the increase of the sum of the two substances content; ④the results of SEM test showed that the " needle" and " filaments" crystal was appeared in internal structure after adding admixtures,the crystals was intertwined more chlsely,and the big hole was less,finally the overall internal structure is more uniform and reasonable.
【CateGory Index】： TU753