泥浆体流变试验的比测

A COMPARING EXPERIMENT FOR SOIL AND WATER MIXTURE ON DIFFERENT KINDS OF VISCOMETER

这次泥浆体流变试验的比测使用了五种不同规格的旋转式粘度计,并把其测试结果与毛管式粘度计的测试结果作了对比。对比结果表明:若用旋转式粘度计测试具有非牛顿体特性的泥浆体,应尽可能采用具有转筒半径比(α=外筒半径R_c/内筒半径R_b)较小的测试室;若是用具有α>1.05的测试室测试,所得的数据则应作特殊处理。毛管式、旋转式两种粘度计的测试结果基本一致,并具相仿的精度。测试结果的离散程度超过仪器的测试误差。这有待进一步研究、查明原因。

After the comparing experiments of rheologic test for the mixture of soil and water on capillary viscometers have been finished in 1990, the next one with different kinds of viscometer are carried out. Five different types of rotational viscometer are used in the experiments, three of them are commercial and two are developed by researcher-selves. The test results are compared each other and also with those from capillary viscometer. The results of this comparison are as follows.1.Because the mixture of soil and water is a non-Newtonian fluid, the distribution of shear rate of the sample in the testing gap of rotational viscometer becomes more complicated, and the deviation of the estimating shear rate will increase in the data processes. Therefore, the test cell with smaller ratio of radius of outer cup to inner bob (a = Re/Ro) should be adopted. If a>1. 05, the eq. (4,5) should be employed and more attention should be paid in the data processes.2.The values and accuracy of test results from these rotational viscometers are similar to that from capillary viscometer. The accuracy is ±0% for rigidity coefficient and±40% for Bingham shear stress. It confirms that the test results from these two kinds of viscometers are coincident with each other.3.The deviations of rheologic factors obtained from rotational or capillary viscometers are in several times greater than the measuring errors of these equipments. The extra deviations over the measuring accuracy may be caused by the comlexity of the property of mixture.