Main Article Content
The water hyacinth which is a weed of rapid growth and is a cause of water pollutions. To solve this problem and provide benefit in term the area under cultivation increasing, this research is focus to study the relationship between floating raft crops thickness and the mass raft drowned fit. Another objective was to investigate the suitable linear equation of above relationship from computational method and experimentalmethod. The results shown that the average density of dried water hyacinth was equal to 0.111 g/cm3 which could not drown. Next, the buoyancy force and mass raft drowned fit were calculated in each raft thickness level, including 4 6 8 and 10 cm. The result from computational method could explained that the raft of water hyacinth to support the weight of the mass increased with increasing thickness of the raft. The raft
thickness 10 cm, it could support the maximum weight of the mass at 6.72 kg and predict the linear equation to y = 0.7398x - 1.089, R2
= 0.9495. For the experimental method, the floating rafts were designed the width and length was equal 50 cm on both sides and desired thickness were divided into four levels as same as the
computational method. The stem of water hyacinth stacked layers in each thickness level and test weights that fit raft drowned. The results showed that the floating raft got the maximum support weight at 7.192 kg at 10 cm thickness and predict the linear equation to y = 0.8259x - 1.0343, R 2 =0.9983. Moreover, the standard deviation was less (0.162 – 1.029) by the mass raft drowned fit comparing between the computational
method and the experimental method, or the both method was not significantly differences in p ≤ 0.05. When a clay which its bulk density is 2.09 g/cm3 and 30 cm of thickness, was placed on the floating raft crops. The raft’s thickness is 191.04 cm that can make it drown, must be designed and built. Therefore, they were further applied the linear equation of both method to construct and design floating raft crops. Moreover, this study is a way to solve the problem of water hyacinth and increase a planting area.