Abstract
The floc structures of sediment in microscale are analyzed based on the use of a scanning electron micrograph (SEM). This analysis makes it possible to directly determine the sizes of flocs and primary particles, leading to an easier determination of the fractal dimension. Further, a method to estimate the effective density of the flocs using the SEM results is evaluated by comparing with the effective density calculated from the settling velocity. It was found that the particle size of the primary particles was normally distributed, which is averagely a half of the floc size. Moreover, the effective density determined from the SEM results was in excellent agreement with that determined from the settling velocity, indicating that the proposal method using the SEM results is valid in the calculation of the effective density of sediment.
