Various methods are used to determine grain size in the civil engineering. One of them is the use of software that, through captured photographs of the area, analyse and produce aggregate grain results.
The purpose of this master's thesis is to compare two different image analysis programs to determine the grain size of the coarse-grained aggregate and sediments and to compare the accuracy of the results with the sieving analysis performed. A sample of the coarse-grained aggregate was taken at the foot of the Belca earth collapse site (31,05 kg), and the gravel sample was took along the Sava Dolinka river in Dovje (41,6 kg). In both cases, 1 square meter of material was confiscated.
The WipFrag program is primarily intended for coarse-grained aggregates, while Basegrain is more suitable for rounded river sediment. After analysing the samples, it can be argued that WipFrag is more accurate in both cases and gives results closer to sieving analysis, but still slightly underestimates the grain size. The use of the latter program itself is much more comprehensible and easy. In other words we notice that in some cases the Basegrain analysis gave a big difference in results (up to 100 % fort he coarse-grained aggregate from the height 1 m and 0,5 m). When determining the height from which the material is taken, it is better to choose a height between 3,5 m and 1,5 m at WipFrag, and there is no specific difference between different heights at Basegrain.
For someone who is working fort the first time with an image analysis program, it is suggested to use WipFrag based on the results found in this master's thesis.
|