为了研究水泥粉煤灰不同掺量对超盐渍土的力学性能影响规律,分别以1%,3%,5%水泥和20%、25%、30%粉煤灰掺入宁夏平罗县姚伏镇的超盐渍土中对其进行固化,并进行7 d 和28 d 龄期的三轴 UU 试验。结果表明：7 d 龄期,相同掺量粉煤灰固化超...为了研究水泥粉煤灰不同掺量对超盐渍土的力学性能影响规律,分别以1%,3%,5%水泥和20%、25%、30%粉煤灰掺入宁夏平罗县姚伏镇的超盐渍土中对其进行固化,并进行7 d 和28 d 龄期的三轴 UU 试验。结果表明：7 d 龄期,相同掺量粉煤灰固化超盐渍土的摩擦角和粘聚力随水泥掺量的增加呈近似线性增加；28 d 龄期,相同掺量粉煤灰固化超盐渍土的摩擦角随水泥掺量的增加趋势呈先慢后快；粉煤灰掺量为20%时,摩擦角随龄期的增加而增加,粉煤灰掺量为25%和30%时,摩擦角随龄期的增加而减小；固化超盐渍土轴向应变较小时,水泥和粉煤灰对主应力差的影响较小,随着轴向应变的增大,水泥粉煤灰固化超盐渍土的作用逐渐增强。建议利用水泥粉煤灰固化超盐渍土时,当固化盐渍土地基三向约束较强时,可以采用1%~3%水泥和20%~25%粉煤灰固化超盐渍土,反之,采用5%水泥和30%粉煤灰或更高掺量的水泥粉煤灰固化超盐渍土。展开更多
45 and 50 composite soil samples were collected, respectively, from twoagricultural fields, that were enclosed and reclaimed from coastal tidal-flat areas in 1996 and 1984respectively, in Shangyu of Zhejiang Province,...45 and 50 composite soil samples were collected, respectively, from twoagricultural fields, that were enclosed and reclaimed from coastal tidal-flat areas in 1996 and 1984respectively, in Shangyu of Zhejiang Province, China, to investigate the physico-chemicalproperties and the hyperspectral characteristics of the saline soils and to make an assessment ontheir relationships. The reflectance spectra of saline soils were measured using a spectroradiometerin laboratory. The mean spectral curves of the saline soils from the two sites different inreclamation year showed that the saline soil taken from the recently reclaimed land with highersalinity demonstrated a lower reflectance intensity in the spectral region from about 550 nm to 2300nm. In addition, nine absorption bands, i.e., 488 nm, 530 nm, 670 nm, 880 nm, 940 nm, 1400 nm, 1900nm, 2 200 nm and 2 300 nm, were chosen as the spectral bands to investigate the relationshipsbetween soil physico-chemical properties by means of Pearson correlation analysis. Finally, thefirst two principal components were calculated from nine absorption bands and used to discriminatethe saline soil samples taken from two sampled fields. The results indicate that it is feasible todetect physico-chemical properties of saline soils from fields reclaimed for varying time periods onthe basis of the hyperspectral data.展开更多
文摘为了研究水泥粉煤灰不同掺量对超盐渍土的力学性能影响规律,分别以1%,3%,5%水泥和20%、25%、30%粉煤灰掺入宁夏平罗县姚伏镇的超盐渍土中对其进行固化,并进行7 d 和28 d 龄期的三轴 UU 试验。结果表明：7 d 龄期,相同掺量粉煤灰固化超盐渍土的摩擦角和粘聚力随水泥掺量的增加呈近似线性增加；28 d 龄期,相同掺量粉煤灰固化超盐渍土的摩擦角随水泥掺量的增加趋势呈先慢后快；粉煤灰掺量为20%时,摩擦角随龄期的增加而增加,粉煤灰掺量为25%和30%时,摩擦角随龄期的增加而减小；固化超盐渍土轴向应变较小时,水泥和粉煤灰对主应力差的影响较小,随着轴向应变的增大,水泥粉煤灰固化超盐渍土的作用逐渐增强。建议利用水泥粉煤灰固化超盐渍土时,当固化盐渍土地基三向约束较强时,可以采用1%~3%水泥和20%~25%粉煤灰固化超盐渍土,反之,采用5%水泥和30%粉煤灰或更高掺量的水泥粉煤灰固化超盐渍土。
基金Project supported by the National Natural Foundation of China(No.40001008),by the German Federal Ministry of Education and Research (BMBF)(No.AZ39742),and by the Science and Technology Department of Zhejiang Province(No.001110445).
文摘45 and 50 composite soil samples were collected, respectively, from twoagricultural fields, that were enclosed and reclaimed from coastal tidal-flat areas in 1996 and 1984respectively, in Shangyu of Zhejiang Province, China, to investigate the physico-chemicalproperties and the hyperspectral characteristics of the saline soils and to make an assessment ontheir relationships. The reflectance spectra of saline soils were measured using a spectroradiometerin laboratory. The mean spectral curves of the saline soils from the two sites different inreclamation year showed that the saline soil taken from the recently reclaimed land with highersalinity demonstrated a lower reflectance intensity in the spectral region from about 550 nm to 2300nm. In addition, nine absorption bands, i.e., 488 nm, 530 nm, 670 nm, 880 nm, 940 nm, 1400 nm, 1900nm, 2 200 nm and 2 300 nm, were chosen as the spectral bands to investigate the relationshipsbetween soil physico-chemical properties by means of Pearson correlation analysis. Finally, thefirst two principal components were calculated from nine absorption bands and used to discriminatethe saline soil samples taken from two sampled fields. The results indicate that it is feasible todetect physico-chemical properties of saline soils from fields reclaimed for varying time periods onthe basis of the hyperspectral data.
