A new test method was introduced to measure fiber distribution in steel fiber reinforced mortar by using image analysis technique. Through specimen preparation, image acquisition, fiber extraction, and measurement of ...A new test method was introduced to measure fiber distribution in steel fiber reinforced mortar by using image analysis technique. Through specimen preparation, image acquisition, fiber extraction, and measurement of related fiber parameters, quantitative analysis of fiber distribution could be obtained by two parameters, namely dispersion coefficient and orientation factor. Effect of boundaries, size and steel fiber content on fiber distribution was discussed. Results showed that, steel fiber distribution was affected by boundary effect, which would be weakened with the increase of specimen size. If the length and width remained constant, the specimen height had a significant effect on orientation factor of fiber, while its influence on dispersion coefficient was not so obvious. With the increase of steel fiber content, dispersion coefficient decreased slightly, and orientation factor deviated from 0.5.展开更多
A series of tests were performed to investigate the macroscopic properties and the stabilization mechanism of calcium lignosulphonate modified expansive soil.Compared with natural soil,soil modified by 4%calcium ligno...A series of tests were performed to investigate the macroscopic properties and the stabilization mechanism of calcium lignosulphonate modified expansive soil.Compared with natural soil,soil modified by 4%calcium lignosulphonate showed 56.5%increased 28 days unconfined compressive strength and 23.8%decreased free expansion rate.The X-ray diffraction analysis results indicate the existence of cation exchange and the reduction of montmorillonite interplanar spacing.The X-computed tomography results demonstrate that calcium lignosulphonate decreased the porosity and optimized the pore distribution.The calcium lignosulphonate also increased the stability of the suspension system according to the Zeta potential results.Moreover,the results of rheological tests show that the moderate amount of calcium lignosulphonate enhanced the yield stress and the plastic viscosity,proving the formation of a strong connection between soil particles.展开更多
基金National Basic Research Program of China (973 Program) (No. 2009CB623200)National Natural Science Foundation of China (Nos. 50908104 and 50978126)
文摘A new test method was introduced to measure fiber distribution in steel fiber reinforced mortar by using image analysis technique. Through specimen preparation, image acquisition, fiber extraction, and measurement of related fiber parameters, quantitative analysis of fiber distribution could be obtained by two parameters, namely dispersion coefficient and orientation factor. Effect of boundaries, size and steel fiber content on fiber distribution was discussed. Results showed that, steel fiber distribution was affected by boundary effect, which would be weakened with the increase of specimen size. If the length and width remained constant, the specimen height had a significant effect on orientation factor of fiber, while its influence on dispersion coefficient was not so obvious. With the increase of steel fiber content, dispersion coefficient decreased slightly, and orientation factor deviated from 0.5.
基金Funded by National Natural Science Foundation of China(Nos.51890904 and 51508090)National Key Technology R&D Program of China(No.2017YFB0309904)the National Basic Research Program of China(973 Program)(No.2015CB655100)。
文摘A series of tests were performed to investigate the macroscopic properties and the stabilization mechanism of calcium lignosulphonate modified expansive soil.Compared with natural soil,soil modified by 4%calcium lignosulphonate showed 56.5%increased 28 days unconfined compressive strength and 23.8%decreased free expansion rate.The X-ray diffraction analysis results indicate the existence of cation exchange and the reduction of montmorillonite interplanar spacing.The X-computed tomography results demonstrate that calcium lignosulphonate decreased the porosity and optimized the pore distribution.The calcium lignosulphonate also increased the stability of the suspension system according to the Zeta potential results.Moreover,the results of rheological tests show that the moderate amount of calcium lignosulphonate enhanced the yield stress and the plastic viscosity,proving the formation of a strong connection between soil particles.
