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Embankment overtopping protection is a practical measure to release large and infrequent floods with no or extremely diminished soil erosion failure due to flowing water over the embankment. The overtopping protection using gabion mattresses, an assembly of a wire mesh frame packed with rock particles, and placed over the embankment crest and downstream slope, is proposed, and its protective ability against soil erosion, structural stability during overtopping and construction performance are investigated. Hydraulics of the overtopping flow is calculated by a nonlinear seepage analysis of flow through the gabion combined with a numerical integration of spatially varied flow over the gabion, then hydraulic shear stress is quantitatively determined to evaluate the soil erosion potential, resulting that it can be prevented safely by placing the gabion underlain by a non-woven geotextile. The structural stability of the gabion mattresses against the sliding failure due to the overtopping flow is assessed by sloping water flume tests and stress-deformation analysis. Embankment slope failure which may be caused by loading of the gabion on the embankment surface is also assessed by circular slip surface calculation. Both assessments show no instability of the gabion sliding along the embankment slope and no degradation in the slope stability. Selecting the farm pond embankment constructed in the early 1900s, the trial test is conducted to construct the gabion mattresses about 200 m² in the placement area, and completed successfully in a very short period and cost-effectively. [ABSTRACT FROM AUTHOR]

This article represents traffic loads on the road structure distribution and evaluation of the vertical and horizontal stresses formation in the soil embankment. This evaluation allows to predict the depth and intensity of the propagation of additional stresses resulting from traffic loads. The calculations were performed in accordance with four normative documents applied in Lithuania, which define the loads on the road structure. The obtained results showed that the area to which the load is distributed has the greatest influence on the intensity of stresses and the distance of propagation. The maximum horizontal stress in the embankment was found to be no more than 70 kPa and the maximum stress propagation depth did not exceed 0.9 m. The results can be applied to a triaxial test apparatus to restore horizontal stresses in the embankment. It is recommended to select a lateral pressure from 20 kPa to 70 kPa for tests provided with triaxial test device. The mechanical properties of the soil determined with triaxial test device and recommended lateral pressure would be representative of the test results obtained in the field of embankment. [ABSTRACT FROM AUTHOR]

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. Article in Lithuanian. Grunto sankasos šlaito statumo ir stabilumo analizė Santrauka Šiame straipsnyje aprašyti dažniausiai transporto keliuose pasitaikančių sankasų šlaitų stabilumo skaičiavimai ir jų rezultatai, taikant modifikuotą Bishop metodą. Skaičiavimais nustatyti mažiausi galimi skirtingų šlaitų statumo ir sankasos efektyvieji vidinės trinties kampai įvertinant skirtingus sankasos (pylimo) pagrindus, sankasos grunto tūrinius svorius, transporto sukeliamas apkrovas ir apkrovų pridėjimo vietas (pečius). Analizuojant gautus skaičiavimo rezultatus, nustatyta, kad siekiant užtikrinti šlaito stabilumą šlaitui esant 1:2 (26,57°) statumo, skaičiuotinis sankasos grunto efektyvusis vidinės trinties kampas turėtų būti φʹd ≥ 28,5°, o šlaitui esant 1:1,75 (29,74°) statumo – φʹd ≥ 29,8°. Kai šlaitas yra 2:3 (33,69°) statumo, šlaito stabilumo užtikrinti nepavyksta. Reikšminiai žodžiai: šlaito stabilumas, šlaito statumas, grunto sankasa, automobilių keliai, transporto apkrovos, modifikuotas Bishop metodas, vidinės trinties kampas.

This article represents traffic loads on the road structure distribution and evaluation of the vertical and horizontal stresses formation in the soil embankment. This evaluation allows to predict the depth and intensity of the propagation of additional stresses resulting from traffic loads. The calculations were performed in accordance with four normative documents applied in Lithuania, which define the loads on the road structure. The obtained results showed that the area to which the load is distributed has the greatest influence on the intensity of stresses and the distance of propagation. The maximum horizontal stress in the embankment was found to be no more than 70 kPa and the maximum stress propagation depth did not exceed 0.9 m. The results can be applied to a triaxial test apparatus to restore horizontal stresses in the embankment. It is recommended to select a lateral pressure from 20 kPa to 70 kPa for tests provided with triaxial test device. The mechanical properties of the soil determined with triaxial test device and recommended lateral pressure would be representative of the test results obtained in the field of embankment. Article in Lithuanian. Grunto sankasos, veikiamos automobilių kelių apkrovomis, įtempių analizė Santrauka Straipsnyje yra apžvelgiamos kelio konstrukcijai tenkančios automobilių apkrovos ir apskaičiuoti vertikalūs ir horizontalūs įtempiai, atsirandantys grunto sankasose. Šie skaičiavimai leidžia prognozuoti nuo automobilių apkrovų atsirandančių papildomų įtempių sklidimo gylį bei intensyvumą. Skaičiavimai atlikti pagal keturis Lietuvoje galiojančius norminius dokumentus, kurie apibrėžia kelio konstrukcijai tenkančias apkrovas. Gauti rezultatai parodė, kad didžiausią įtaką įtempių intensyvumui ir sklidimo atstumui turi plotas, į kurį išskirstyta apkrova. Nustatyta, kad didžiausias horizontalus įtempis, tenkantis grunto sankasai, yra ne didesnis nei 70 kPa, o didžiausias įtempių sklidimo atstumas neviršija 0,9 m. Rezultatus galima pritaikyti atliekant statinius grunto bandymus su triašio slėgio aparatu, kada norima atkurti horizontalius sankasoje vyraujančius įtempius. Rekomenduojama šoninį slėgį parinkti nuo 20 kPa iki 70 kPa. Su šiuo šoniniu slėgiu nustatytos grunto mechaninės savybės būtų reprezentatyvios, taikant gautus bandymų rezultatus sankasų projektavimo srityje. Reikšminiai žodžiai: įtempių analizė, apkrovų parinkimas, grunto sankasa, automobilių keliai, vertikalūs įtempiai, horizontalūs įtempiai.

Trangkil Housing Welfare and the New Trangkil - Sukorejo Village, District Gunungpati Semarang experiencing heavy rains triggered landslide Continuous Semarang City area since Wednesday (22/01/2014) until Thursday (01/23/2014). Successive landslides occurred early Thursday until 07.30. For 15 years Trangkil Sejahtera housing residents live, the worst avalanche of new events happening this time. Seven houses in Trangkil Sejahtera RT 3 RW 10 damaged by the landslide that occurred. While in New Trangkil Housing RT 6 RW 10, 32 houses were severely damaged and even some of them to the ground. The sliding slope in Housing Trangkil Sejahtera and Trangkil New - Village Sukorejo, District Gunungpati Semarang on January 23, 2014 is one of many landslide in a residential area in the district Gunungpati Semarang declared as landslide prone areas by the Directorate of Environmental Geology, Bandung. It is necessary for geotechnical evaluation to support the effectiveness of the slope reinforcement design selection, the necessary understanding of the physical and mechanical properties of soil based on soil test series. Barrow unfavorable, changes in land use, drainage systems are poorly integrated and rain triggered avalanches are the main factors causing the landslide. These four factors are interrelated core is Trangkil Sejahtera Housing Gunungpati Semarang infrastructure is not well prepared to anticipate landslides.

Forestry activities are a widely accepted means of restoring degraded lands. In the semi-arid Negev of southern Israel, extensive lands have been modified for runoff-harvesting-based afforestation projects comprised of contour bench terrace systems (also called shichs/shychs/shikim). However, some alarming evidence in recent years calls for assessing the environmental impact of these forestry lands. We assessed the effects of contour bench terrace afforestation systems on herbaceous vegetation productivity and the soil quality of the uppermost layer (0–5 cm depth) and the 0–80 cm profile, in 2-year-old and 9-year-old afforestation systems, and natural, unperturbed hillslopes in the multi-aged Ambassadors' Forest. Results revealed considerable differences between the sink (contour bench terraces) and source (inter-terrace spaces) areas of the afforested lands. Normalizing data to the relative cover of these areas revealed similar herbaceous vegetation biomass and soil wetting front values for the natural hillslopes (1.47 Mg ha − 1 and 59.8 cm, respectively) and 9-year-old afforestation systems (1.64 Mg ha − 1 and 59.3 cm, respectively), and significantly lower values for the 2-year-old systems (0.07 Mg ha − 1 and 49.4 cm, respectively). Unexpectedly, the opposite trend was recorded for soil hygroscopic moisture content, which was significantly smaller for the natural hillslopes (1.7%) and 9-year-old systems (1.9%) than the 2-year-old systems (3.2%). Soil bulk density was also significantly affected by afforestation treatment, following the trend 2-year-old systems > 9-year-old systems > natural hillslopes (1.57, 1.55, and 1.53 Mg m − 3 , respectively). Soil penetration resistance varied greatly throughout the 80-cm soil profile. There was no significant effect of afforestation treatment on soil gravimetric moisture content (in the spring). Overall, soil quality and herbaceous vegetation cover were only slightly greater on the north-facing aspects than those on the south-facing aspects. We concluded that the establishment of contour bench terraces increases geodiversity on a hillslope scale, but removes the surface soil (A horizon) from extensive areas, increases soil compaction, and decreases herbaceous vegetation production, adversely affecting soil quality, pastoral productivity, and ecosystem functioning and health in the short term. However, over the long term, self-restoration of small-scale geodiversity and functioning of the geo-ecosystem is suggested to improve soil quality and increase herbaceous vegetation productivity in these dryland afforestation systems. [ABSTRACT FROM AUTHOR]

The distribution of lead in and below a soil embankment used as a stop butt for lead bullets at a sport shooting range for more than 30 years was investigated. A vertical profile, just behind the shooting target, was mapped by 54 soil samples characterized by contents of lead bullets, soil lead, and easily leachable lead as measured in a leaching test (L/S 2). At the target, the soil contained up to 40% metallic lead and 5 to 10% lead associated with the soil particles (<2 mm). The leaching test showed concentrations of dissolved lead in the range 5 to 20 mg/l. However, in the bottom of the stop butt (about 1 m lower than the target) soil lead was only slightly elevated, and no increase in lead was found below the stop butt in the original soil profile. In the lower part of the stop butt, pH was around 5, which is considered to favor lead migration, but in the soil samples with leadbullets present pH was between 6 and 7. The elevated pH values, probably caused by the corrosion of lead bullets, may have been a significant factor in limiting the migration of lead in the stop butt. The investigation showed that the lead in the stop butt did not affect thesurroundings, but that the high lead content of the soil would require that this be treated as waste if the facility was abandoned. [ABSTRACT FROM AUTHOR]