Following the 10th freeze-thaw cycle the particles began to fragment with the diameter of the particles diminished, i.e., the result of the freeze-thaw effect that led to the diminution of particle’s roundness in Figure. 7. As a whole, with the increasing number of freeze-thaw cycles the percentage amount of smaller roundness values diminished, and the percent amount of large roundness was higher, which suggested that the shape of the particle was closer to a circular shape.1 After 50 and 100 freeze-thaw cycle the roundness of particles increased. i.e. it is like the example in Fig. 7 where the freeze-thaw phenomenon caused being a rounder particle. This is due to an increase in the aspect ratio for smaller values while a decline in the aspect ratio for high values. This is in line with the varied pattern of roundness of the sample (FS) in Fig.1
8. Furthermore the roundness span for specimen (L) is the most extensive and is being followed by that of specimen (FS) (FS) and specimen (CS) and the most compact that of the specimen (VFS). Specimen (FS) particle images following those freeze-thaw cycles ( zero freeze-thaw cycles (b) 5 freeze-thaw cycle; 10 freeze-thaw cycles 50 freeze-thaw cycles, e 100 freeze-thaw cycles).1 On the whole, the roundness of the specimen (VFS) has the biggest and highest concentration. Analyses and discussions. The change in percentage of a certain amount of roundness four soil specimens following several freeze and thaw cycles. ( an Specification (L) and B Specification (CS) (VFS); C Specificimen (VFS) (d The Specimen (FS)).1
The shape and texture of particles is tightly linked to the geological setting. Comparing the roundness of loess before freeze-thaw and following 100 freeze-thaw cycles, the roundness increased of the loess by 0.0636, the roundness of coarse sand was increased by 0.1715 while that of fine sand was increased by 0.0452 as well as the roundness of fine sand was increased by 0.0129.1 According to an introduction in the book the shape and appearance of these particles can provide important information regarding their origin of deposition and transport history 5,6,7 and 8,9,10,11 . It is apparent how the roughness grew the most, which means how round the particles that have big particle size has increased by the largest amount.1 In an aeolian setting there are three methods by which soil particles are transported by wind including surface creep, saltation and suspension 15,27 and 28 . Particularly, the particulary, specimen (VFS) is considered an example to analyze.
Because of the size-selective nature of transport and saltation abrasion, Eolian ecosystems are the majority of subrounded, well-sorted grains 15,16,17,18 .1 From the diagram of roundness changes of the specimen (VFS) It can be observed that the particle’s roundness improves overall after 5 freeze-thaw cycles in addition, the size of the particles also increases after the 10th freeze-thaw. The roundness of aeolian deposit particles increases as the distance to the area of the source 30 .1 This indicates that after 5 freeze-thaw cycles the shape of the particle gets rounder After 10 freeze-thaw cycle, the particle’s shape gets rounder which implies that during the freeze-thaw cycle of 0-10 cycles The freeze-thaw effects increase the particle’s roundness. Similarly, when the transport mode is fluvial transport, the particle size decreases and the roundness and sphericity increase due to the shape sorting and increase of transport distance 31,32,33,34,35,36,37,38 .1 After the 50th cycle of freeze-thaw when compared to the roundness of the particles following the 10th freeze-thaw cycle it is found that the roundness of the particle has reduced, which is caused by the freeze-thaw effects that causes particle fragmentation, which results in the reduction of roundness of particles.1 In the previous literature we can see that both wind and fluvial transport may cause growth of the roundness of particles.
When you go through 100 cycles of freeze-thaw, the particle roundness is increased and is higher than at the end of 10 freeze-thaw cycles, this indicates that freeze-thaw effects makes the particle rounder.1 The freeze-thaw effect alters the particle’s morphology that differ from aeolian or river transport methods, and have distinct specific characteristics. In other words, when you go through zero to 100 freeze-thaw cycles, the samples (VFS) was subjected to the first the rounding process (0-10 freeze-thaw cycles) before dispersing (10-50 freeze-thaw cycles) before finally rounds (50-100 freeze-thaw cycles).1 The process of determining the size of the particle dimension, aspect ratio , and roundness changes due to freeze-thaw effect are depicted in the concept diagrams.
As illustrated by the concept diagram in Fig. 7. The diagram is shown in Fig. 10. Conceptual diagram showing the variation in the roundness of particles caused by freeze-thaw cycles.1 There are two primary stages of the freeze-thaw phenomenon that causes particle size, aspect ratio , and roundness alteration.
In the analysis above we can conclude that the freeze-thaw cycle could modify the particle’s roundness as well as repeated freeze-thaw cycles could cause an increment or decrease in the particle roundness.1 In the first caused by the tension in the temperature and the alteration of the water phase on the surface, the cracks appear in the surfaces of the coarse particles. To describe the impact of freeze-thaw upon particle roundness The conceptual diagram is explained as follows: As a result of the freeze-thaw effect particles break up and the roundness decreases and the size decreases.1
When water penetrates into the cracks the water phase transforms into an ice (volume rises by 9%) which causes the expansion and penetration of the cracks. The fragmented particles are characterized by edges with small roundness. This eventually results in particle fragmentation. particle size shrinks, roundness, and aspect ratio changes.1 Repeated freeze-thaw cycles result in fragmentation of the edges of particles and an increase in roundness.
In the second phase with the freeze-thaw process, the sliding of particles happens, the edges of particles gets broken, while the roundness the particles increase. In the study of Fig. 6, it is conclusively concluded that repeat freeze-thaw cycles may cause an increment or decrease the particle roundness.1 When repeated freeze-thaw actions are performed, an aspect ratio for particles diminishes, and the proportion of particles that have an aspect ratios that is 1.26 is the most common. Figure 7 shows that with repeated freeze-thaw cycles, particle size can change as roundness decreases for the same particles.1
Conceptual diagram of freeze-thaw effects altering particle aspect ratio as well as circularity (Note that this drawing can be applied to larger sizes of particles). To analyze the relationship between the size of the particle and roundness in freeze-thaw cycles, a chart of roundness and size of particles changes for all types of soil following freeze-thaw cycles has been drawn (Fig. 8).1 In the roundness analysis of four samples it was discovered in the course of 100 freeze-thaw cycles, the roundness of the particles is increased. Changes in the size and roundness for each type of soil following freeze-thaw cycles. ( an Specification (L) and B (Specimen (CS) (VFS); the c Specificimen (VFS) (d the Specimen (FS)).1
In other words, the cryogenic weathering process can cause an increase in roundness of the particle. In figure. 8, the green dot line shows the initial distribution of roundness in the specimen. This is consistent with the fact that when the transport is a fluvial medium The roundness of particles increase following a certain distance of flow transport .1 It is apparent in the graph that the roundness decreases in loess as particles grow in size, whereas rough sand’s roundness, extremely fine sand and fine sand do not diminish, but is fluctuating within a particular interval. This is in accordance by the observation that the most important shape of particles is well-sorted subrounded particles in the aeolian environment 15,16,17,18 .1 In general, roundness for very fine sand is by far the biggest, then fine sand and coarse sand.
So, the increased roundness of particles following 100 freeze-thaw cycles is not used as a basis to decide whether the particles are subject to cryogenic weathering. The least round is the loess. However, with repeated freeze-thaw effects as well as the particles’ roundness getting larger, particle aspect ratio also diminished.1 With the increasing number of freeze-thaw cycles the roundness of the various particle sizes decreased or increased as a result of the rounding or fragmentation of the particles that resulted in the change in roundness. Following freeze-thaw particles with an dimensions of 1.26 has the highest amount of.1
When you go through the 10th freeze-thaw, it is apparent that the roundness and roundness for loess as well as fine sand is less than the original value while the roundness of loess after other freeze-thaw cycles are greater over the value of the first.