秸秆纤维改良高含水率疏浚淤泥的干缩特性研究

开展室内干缩试验,探究秸秆纤维掺量、尺寸等对疏浚淤泥干缩特性的影响。通过测定裂缝开展临界时间T_(IC)、最大裂缝宽度、表面裂隙率等物理指标评价改良效果。试验结果表明:秸秆纤维可以有效促进疏浚淤泥干缩;随着秸秆掺量增大,T_(IC)逐渐降低并在掺量达到3%后趋于稳定;最大裂缝宽度与秸秆掺量呈负相关;表面裂隙率随纤维掺量增加而先减小后增大,纤维掺量为5%时的表面裂隙率最小;秸秆掺量≤1%时,纤维尺寸对T_(IC)、最大裂缝宽度、表面裂隙率的影响不明显,秸秆掺量1%时,3个物理参数随纤维尺寸增大均先减小后增大,且尺寸为0.6～1 mm的秸秆纤维的参数值最小。

Study on the Shrinkage Characteristics of Straw Fiber Improved Dredged Sludge with High Moisture Content

Indoor drying shrinkage test is carried out to explore the influence of straw fiber content and size on the drying shrinkage characteristics of dredged sludge. The improvement effect is evaluated by measuring the critical time TIC of crack development, maximum crack width, surface crack rate and other physical indexes. The results show that straw fiber can effectively promote the drying shrinkage of dredged sludge; With the increase of straw content, tic gradually decreased and tended to be stable after the content reached 3%; The maximum crack width was negatively correlated with the content of straw; The surface crack rate first decreases and then increases with the increase of fiber content, and the surface crack rate is the smallest when the fiber content is 5%; When the straw content is less than or equal to 1%, the fiber size has no obvious effect on tic, maximum crack width and surface crack rate. When the straw content is more than 1%, the three physical parameters first decrease and then increase with the increase of fiber size, and the parameter value of straw fiber with size of 0. 6~1 mm is the smallest.