ANALYSIS OF EMBANKMENT SLOPE STEEPNESS AND STABILITY

This paper describes the stability calculations of the most common road embankments slopes and their results using the modified Bishop method. By searching for the smallest possible effective angle of internal friction of the different slope steepness embankments, the possible different bases of the embankment, the weight of the embankment soil, the load caused by transport and the location of load application (shoulder) were evaluated. Analyzing the obtained calculation results, it was determined that at a slope of 1:2 (26.57°) steepness, to ensure slope stability, the calculated effective internal friction angle of the embankment soil should be φʹd ≥ 28.5°, and at a slope of 1:1.75 (29.74°) steepness – φʹd ≥ 29.8°. When the slope is 2:3 (33.69°) steepness, the stability of the slope cannot be guaranteed.

Advanced Technology for Improving Degraded Slopes in Mountainous and Foothill Zones

The authors presented the technology and mechanization means for the restoration of degraded mountain areas with slope steepness up to 15 degrees.(Research purpose) To determine the optimal distance between the springy racks of the chisel cultivator KCHG-2.4; to characterize the developed block-module of the multifunctional unit KCHG-2.4, which performed three operations after the slitting process: sowing grasses, applying mineral fertilizers and rolling the sown seeds and granular fertilizers into the soil; to determine the effectiveness of the developed agricultural practices that increased productivity and the environment-forming role of mountain phytocenoses.(Materials and methods). The tests were carried out in the mountainous zone of North Ossetia - Alania at an altitude of 1540 meters above sea level with slope steepness up to 15 degrees. The experimental area was divided into three replicates. Each replicate was 2.4 meters wide, 10 meters long, dividing stripes 1 meter, side stripes 2.4 meters. The total test area, located across the slope, was 184.2 square meters.(Results and discussion) The springy Väderstad strut of the KCG-2.4 unit was used to slit the mountain slopes. For overseeding, a three-component grass mixture of Phleum pratense L., Dactylis glomerata L. and Trifolium pratense L. was proposed at a seeding rate of 15 kilograms per hectare. When applying mineral fertilizers, the following composition was used (in the active ingredient): ammonium nitrate – 35 percent; superphosphate – 20; potash salt – 40 percent, in total 445 kilograms per hectare. An increase in dry aboveground mass of 3.02-4.19 tons per hectare and the accumulation of underground plant mass in the range of 1.84-12.62 tons per hectare were got, depending on the variant of the experiment.(Conclusions) The authors found out that, a higher yield was obtained with a distance between the slits of 1.5 meters for 3 years of observations. It was found that the use of the unit increased the collection of feed units from 0.81-1.68 to 4.06-4.98 thousand per hectare. Taking into account all costs, the cost of one feed unit was 8.76 rubles.

Application of geoinformation systems for a complex analysis of data from agrochemical and soil-erosion monitoring of soils

The article describes the development of a geoinformation system module (using the example of GIS “Agroecologist Online”) to automate the complex analysis of agrochemical and soil-erosion monitoring data. With the help of an additional GIS module, it allows you to generate reports with tabular data of various groupings: by soil type and degree of erosion; by soil type and slope steepness; by soil type, degree of erosion and exposure; by soil type, slope steepness and exposure; by soil type, degree of erosion, slope steepness and exposure. Based on the presented tables, using the module, it is possible to analyze the indicators of agrochemical and soil-erosion survey in a comprehensive manner. The module also allows you to predict the level of yield of certain crops, to timely identify the deterioration of soil resources for a certain territorial unit (within a specific farm, a specific region, as well as on the territory of the entire Russian Federation).

Design and Research Process of Microstrip Low-Pass Filters with High Slope Steepness

This paper presents the results of design process and scientific investigation of planar low pass filters with cut-off frequencies of 6 and 7 GHz. Main features of this design are high steep performance, high level of rejection out of band (in comparison to conventional topologies), high filter order and small occupied area. The analysis of high absorptive electromagnetic material influence on filter performance are shown as well

Analysis of the difference in depths and variation in slope steepness of the Sunda Trench, Indonesia, east Indian Ocean

The paper discusses geomorphology of the Sunda Trench, an oceanic trench located in eastern Indian Ocean along the Sumatra and Java Islands of the Indonesian archipelago. In particular, it analysis the difference in depths and variation in slope steepness between the two segments of the trench: the southern Java transect (coordinates 108.8°E 10.10°S to 113.0°E 10.75°S) and the northern Sumatra transect (97.5°E 1.1°S to 101.0°E 5.5°S). The thematic maps and geomorphological modelling were plotted using Generic Mapping Tools (GMT). The materials include high-resolution data on topography, geology and geophysics: GEBCO 15 arc-minute resolution grid, EGM2008 2.5 minute Earth Gravitation Model of 2008, GlobSed global 5‐arc‐minute total sediment thickness and vector geological datasets. In addition to the GEBCO-based bathymetric data, geological, topographic and geophysical maps, the results include enlarged transects for the Java and Sumatra segments, their slope gradients and cross-section profiles, derived from the bathymetric GEBCO dataset. The geomorphology framework of the Sunda Trench is largely controlled by the subduction of the Australian plate underneath the Sunda microplate. The geological processes take place in basin of the Indian Ocean at different stages of its evolution and influence the nature of the submarine geomorphology and geometric shape of the trench. Sunda Trench is seismically active part of the Pacific Ring of Fire. A large number of the catastrophic earthquakes are recorded around the trench. The histograms shows variation in depths along the segments of the Sumatra and Java. The Java segment has a bell-shaped data distribution in contrast to the Sumatra with bimodal pattern. The Java segment has the most repetitive depths at -2,500 to -5,200 m. The Sumatra transect has two peaks: 1) a classic bell-shaped peak at depths -4,500 m to -5,500 m; 2) shelf area with a peak from 0 to -1,750 m. The data at middle depths (-1,750 to -4,500 m) have a frequency <300 samples. The most frequent bathymetry for the Sumatra segment corresponds to the -4,750 m to -5,000 m (2,151 samples). Comparing to the Sumatra segment, the Java segment is deeper. For the depths >-6,000 m, there are only 138 samples for the Sumatra while 547 samples for Java. Furthermore, Java segment has more symmetrical geometric shape while Sumatra segment is asymmetric, one-sided. The Sumatra segment has a steepness of 57.86° on its eastern side (facing Sumatra Island) and a contrasting 14.58° on the western part. The Java segment has a steepness of 64.34° on its northern side (facing Java Island) and 24.95° on the southern part (facing Indian Ocean). The paper contributes to the studies of the submarine geomorphology in Indonesia.

Numerical Simulation of the Solitary Waves Propagation and Run-up in Shallow Water

Purpose. The paper is aimed at investigating the propagation of solitons in a shallow basin, assessing the nonlinear effects resulting from the wave run-up on a gentle coast, and at comparing the estimates obtained using different numerical models with the available analytical dependencies. Methods and Results. The results of numerical simulations carried out using two nonlinear models of long waves (the author's model and the Simulating WAves till SHore (SWASH) one) are represented in the paper. The solitary wave profiles were obtained during its propagation in the part of a basin with constant depth conjugated with the inclined bottom. The process of a wave run-up on the coast was simulated using the algorithm of fluid movement along a dry coast. It is shown that when a soliton propagates in the basin part with constant depth, the nonlinearity effects are manifested in deformation of a wave profile. In other words, increase of the wave initial amplitude and the distance traveled by a wave is accompanied by growth of the wave front slope steepness. This, in its turn, leads to increase of a splash when the waves run-up on the coast. The estimates of the run-up heights resulted from different numerical models are in good agreement. Conclusions. The calculated values of the maximum wave run-up on the coast for the non-deformed waves, the length of which is equal to that of the traversed path, are close to the estimates obtained analytically. For the waves with the deformed profile, the front slope steepness of which increases with propagation over long distances, the run-up heights increase with growth of the wave initial amplitude. In such a case, it is desirable to replace the analytical estimates with the numerical ones. The run-up height of the deformed waves can exceed the wave initial amplitude by four or more times. The results obtained in this study can be useful in projecting the coastal protection constructions with the regard for preserving the coastal ecology and economy.

Effect of Slope on Infiltration Capacity and Erosion of Mount Merapi Slope Materials

Infiltration which occurs on slope has a specific behavior that can be parameterized. One of the reasons is because the slope generates less ponding on the sloping soil surface. This condition affects infiltration rate and surface runoff proportion of water from any kind of rainfall distribution in time. Since surface runoff tends to be higher, erosion rate is also to be higher on slope. The slope steepness is the most important parameter of a slope. In this study, the effect of slope steepness on infiltration capacity and erosion rate of Mount Merapi bare slope material were tested in a laboratory using rainfall simulator. Three values of slope steepness of 36%, 47%, and 58% were used. The rainfall intensity was set constant and was found has rate of 116,312 mm/hour. The infiltration rate was measured by volumetric balance principle and the erosion rates were measured by collecting the eroded grains at the downstream end tank. Infiltration rate was evaluated by using Horton method and the average erosion were analyzed from the eroded grain data for each test. After fitting the recorded infiltration rate data to the Horton equation, the infiltration capacity was obtained. The results were the relationship between slope steepness and the affected the infiltration capacity and erosion for each test. Infiltration capacity is found to increase and the decrease with the increase of slope steepness while erosion rate is found to increase on the steeper slope. The increase of erosion range is between 15% to 33% for each 1o increase of slope steepness. In addition, polynomial and exponential equations were developed to express the relationship between slope steepness and infiltration capacity and also the erosion rate.

ASSESSMENT OF CRITICAL SLOPE OF AVALANCHE – HAZARDOUS MOUNTAIN SLOPE

One of the mandatory conditions for the formation of snow avalanches is the presence of a certain slope of the mountain slope. The forces acting on a snow layer located on a mountain slope, the conditions of its equilibrium and possible shift without taking into account external forces are considered in the article. The critical slope steepness is calculated

How different are effects of vinasse biochar on soil erosion in Loess and Marl soils?

&lt;p&gt;Nowadays soil erosion control using different amendments has grown up worldwide. However, the application of transformed materials like biochar has not been adequately studied. In the same vein, the application of biochars produced from waste materials that harm nature, and impose cost to managers and producers is a valuable approach for optimal utilization of the resources. Towards this, the performance of biochar produced from deleterious raw vinasse as the main by-product of sugarcane industries in controlling soil splash and interrill erosions on two marl and loess soils from Iran was investigated. The study was performed in 0.5 m&amp;#215;0.5 m plots in three replicates installed in the field with a slope steepness of 25% subjected to a simulated rainfall with an intensity of 50 mm h&lt;sup&gt;-1&lt;/sup&gt; and 0.5 h duration. Analysis of the results obtained from the splash and interrill erosions during the rainfall-runoff process showed that biochar decreased soil loss compared to the control plot on Marl soil but to a small extent (p &gt; 0.05). However, the plot treated with biochar on the loess soil revealed significant (p&lt;0.05) reduction in soil loss in comparison with that of the control plot. That study clearly demonstrates the addition of biochar may promote stability and limit both runoff and soil erosion. However, such effects strongly depend on the type of soils.&lt;/p&gt;

Study of physical environment based on land system map of Kabupaten Bandung

<p><em>The environmental damage in Kabupaten Bandung is critical. To solve the environmental problems, the integrated spatial data of the physical environment is required. Land system data as the integrated spatial data which describes the characteristics of land are useful for the analysis and evaluation of the environmental conditions. The objective of the study is to describe the characteristic</em><em>s</em><em> of the physical environment of Kabupaten Bandung based on the land system map for the input of decision</em><em>-</em><em>making in achieving sustainable development.</em><em> The study used the spatial analysis and descriptive analytical method. The land system data was obtained from the Badan Informasi Geospaasial (BIG). The results show that the landforms in Kabupaten Bandung are dominated by volcanic and fluvial landforms. The volcanic landforms </em><em>has</em><em> morphology dominated by mountainous areas with the slope steepness more than 45% and the soil types of andosols. The land capability of these mountainous areas belongs to grade 7 (for conservation areas).</em><em> </em><em>The fluvial landforms are lacustrine plains, which are prone to flood due to inundation. From this study, it is concluded that the land utilization in Kabupaten Bandung, particularly in mountainous areas, is not in accordance with the land carrying capacity. To achieve the sustainable development, the land utilization should consider the regulation of spatial planning, by which the lands with slope steepness more than 40% are categorized as protected areas. </em></p><p><strong><em> </em></strong></p><p><strong><em> </em></strong><strong><em>Keywords: </em></strong><em>Land system, land characteristics, landform, suistanable development</em><em></em></p>