Side Slope Research Articles

A Promising Method of Utilization of Ash and Slag Waste of Variable Composition at Coal-fired Power Plants

A comparative analysis of ash and slag waste (ASW) of six deposits, differing in quantitative chemical and phase composition, granulometry, melting temperature and other properties, is presented, and the production of a material promising for the construction industry is proposed – aggloporite, the production technology of which practically does not depend on the composition and properties of TPP ash. Aggloporite can also be used in road construction to form side slopes. The proposed method of recovery of large volumes of ash and slag waste accumulated at a number of power plants opens up opportunities to improve the environmental situation in the areas located in the vicinity of coal power plants, free up significant land areas occupied by ash and slag waste storage facilities, and reduce the harmful effect of waste on soil, water and air.

Analysis and design of auto-adaptive leveling hydraulic suspension for agricultural robot

The application of agricultural robot in hilly and mountain areas faces several problems, such as bad walking performance, easy tilt, and low safety. The auto-adaptive leveling hydraulic suspension for the agricultural robot can help to eliminate some sort of problems. The design of such system is the main aim of the article. The hydraulic system with load-sensing system and its controlling model were established and then the load-sensing system was modeled and simulated in Advanced Modeling Environment for SIMulation. The optimal proportional–integral–derivative parameters were determined by the optimized algorithm. The simulation results illustrated that the inlet and outlet pressure difference of throttle and the flow rate through throttle are 42 bar and 29.65 L/min, respectively, all the time when the load pressure varies from 0 bar to 100 bar. The load-sensing system has good power follow-up and high control accuracy. And then the experimental bench of auto-adaptive leveling hydraulic suspension was researched and developed to verify the leveling performance. The experimental results demonstrate that auto-adaptive leveling hydraulic suspension can keep frame leveling dynamically on upslope, downslope, side slope, and continuous undulating road surface. The maximum errors of the pitch angle and the tilt angle are −0.93° and 0.97°. The feasibility of the designed hydraulic suspension was verified. The research methods in this article can provide theoretical basis for the design of other auto-adaptive leveling systems in hilly and mountain areas.

Identification of operational parameter levels that optimize the production in solar stills with plain, corrugated, and compartmental basin.

Researchers integrate various operational parameters in the conventional type solar still to improve the distillate production. But maximum production can be obtained only when the optimum parameter levels which suit the solar still design are identified and incorporated. In this study, an attempt has been taken to identify the optimum level of four operational parameters-Mass of Heat Storage Material, Basin Water Depth, Basin Cover Thickness, and External Mirror Position, which suit well in plain basin, corrugated basin, and compartmental basin solar still. The parameter levels were combined as per L9 orthogonal array and the distillate production obtained under different combinations of operational parameter levels was analyzed using S/N ratio analysis, mean response method, analysis of variance, and regression analysis. The analysis revealed that the optimum mass of heat storage material was 16 kg in plain basin, 12 Kg in corrugated basin, and 10 Kg in compartmental basin still. The efficiency of corrugated basin and compartmental basin solar stills was maximum at a lower basin water depth of 15 mm and 10 mm respectively. But plain basin still efficiency was maximum at a higher basin water depth of 20 mm. The optimum basin cover thickness was 4 mm in all the solar stills, in spite of a difference in the structure of the basin. In the same way, the distillate production was maximum when the external mirrors were positioned on the two sloping sides of the solar still (east and west side). The expected production from the solar stills integrated with the optimum parameter levels was estimated using regression analysis and mean response method. The average distillate production which was 3304, 3493, and 3629 ml/m2.day in the modified (not with optimum parameter levels) plain basin, corrugated basin, and compartmental basin solar stills respectively, improved to 6414, 7153, and 7629 ml/m2.day respectively when they were modified with optimum parameter levels and the increase in production was 94 %, 105 %, and 110 % respectively.

Insertion loss (IL) of finite sound barriers of different contours - An introduction to geometrical solutions in 3-D space

The design of finite sound barriers noise sources and control points requires calculations beyond those that are used when the Maekawa formula is applied, since the problem involves polygon sd barriers located in various possible orientations in 3D space. We present here some means that are linked to basic mathematical geometrical tools. Those means are relatively simple, as compared to the physical formulation of the relevant diffraction solutions for sound barriers (e.g. Rosenhouse, 2019, 2020). Such calculations can apply algebraic, trigonometric or vector analysis and their combinations to define the geometries of barrier IL. This approach includes the location of the sources and control points, which are essential as data for finding IL and other issues of environmental acoustics. We will show solutions including results of IL for a common rectangular barrier, as compared to IL of a barrier with a sloped top and side, among other possibilities.

Slope Stability Analysis of Highway Embankment with Different Height and Slope by Varying the Properties of Soil

The analysis of slope stability has received wide attention nowdays because of its practical importance. To provide steepest slopes which are stable and safe, various investigation are ongoing. The main objective of the project is to analyze slope of embankment by calculating factor of safety. So that an appropriate side slope can be chosen and use for the construction of highway. For this, limit equilibrium analysis has been done using GEO5 software. Swedish circle method (Graphically) has been used to performed manually analysis. In the present study, data collected from the site which is located near Shivni Village, Ner-Yavatmal road. “The construction of Samruddhi Mahamarg” is being constructed at that site. It is having high embankment heights upto 9meter. The values of unit weight of soil(γ), angle of internal friction(ϕ), cross sectional details of embankment and side slope of embankment were taken from that site. In this study, embankment of different heights (3 to 9m) under different 8 slopes (i.e. 1:2, 1:1.75, 1:1.5, 1:1.25, 1:1, 1:0.83, 1:0.7, 1:0.58), different values of cohesion and friction angle were considered. The analysis has been performed on two different cases: Case I stands for single layer of soil and Case II stands for double layer of soil by varying the value of cohesion and angle of internal friction the changes occur in the value of factor of safety were checked by comparing both results obtained by manual method and by GEO5 software. From this investigation it is found that increasing the value of cohesion and angle of internal friction, the factor of safety against slope stability increases. And for a particular height of embankment factor of safety increases with increase in the flatness of slope. From these results, it is better to use C-ϕ soil rather than ϕ soil as it gives maximum FOS as compared to sandy soil. From the analysis of doubled layered soil, it has been concluded that condition 2(with both soil cohesive) found satisfactory better with respect to condition 1(when one soil cohesive and one soil sandy). By considering condition 2 (both soil cohesive), it has been found that the increment of 25 to 30% in the FOS of condition 1 takes place.

Sensitivity Analysis of Dam Breach Parameters for Variation Capacity Earthen Dams

Sensitivity analysis is an effective tool to determine the robustness of an assessment by examining the extent to which the results are affected by changes in input. In this study, the FAST method was applied to analyse the sensitivity to the earth dam failure process. Four (04) input variables were selected including breach development time, breach width, side slope, and initial breach position. The effects of these parameters on the two (02) outputs i.e., the maximum outflow, and rising time were assessed. The study was applied to 08 reservoirs with different capacities. The sensitivity analysis showed that the development time and initial breach location dominantly affect these outputs. Additionally, development time is the most important factor in rising time. The lateral slope has an insignificant effect on outputs. The effect of breach width can be neglected to rising time, however, its influence on maximum outflow is significant. The results of this study show the role of input variables in the flow hydrograph due to dam failure. Through this research, the workload of the breach parameter analysis process can be substantially reduced.

Laboratory Investigation of Geobag Revetment Performance in Rivers

Geobag (sand-filled geotextile bags) revetments have recently emerged as long-term riverbank protection measures in developing countries; however, their performance is still not well understood. The hydraulic stability of geobag revetments used for riverbank protection has been studied within an extensive laboratory programme to improve our understanding of the complete failure processes of geobag revetments. A 1:10 scale distorted physical model was tested in a laboratory flume, comparing a range of different construction methods and revetment side slopes, subjected to different flow loading. The results indicate that whilst failure mechanisms are highly dependent on water depth and revetment slope, the construction method had no noticeable impact. It was thus concluded that the dominating factor is the friction between individual geobags, which itself is dependent on bag longitudinal overlap rather than a specific construction method.

Study on the Shape Optimization of Composite Slope at the End of Irregular Boundary Open-Pit Mine

In order to optimize the shape of the compound slope at the end of the open-pit mine under the condition of non-irregular boundary, the compound slope composed of the stope end and the inner dump in the south of the open-pit mine in Pingshuo is studied. Due to the impact of land acquisition, the space of external dump is seriously insufficient, and with the development and change of mining engineering and the influence of geological structure, the problem of compound form optimization and the release and utilization of internal drain space in the south side is generated. Through field investigation and theoretical analysis and numerical analysis method, on the basis of investigating the ore party production status, to establish a 3 d geological model, select two battery profile typical position, using rigid body limit equilibrium method from the perspective of 2 d, in the full study south help shrink battery limit compound stope side slope and mine safety distance, flat width, and the direction of dump active line and the relationship between the stability design of multiple slope configuration scheme, through the various methods of slope stability, enforceability and comparing some important parameters such as displacement capacity, ultimately determine the technology feasible economic and reasonable boundary zone composite slope space form. Based on the above research results, FLAC3D software was used to study the stress-strain relationship inside the slope, revealing the deformation and failure mechanism and stability of the composite slope in the south bound area. The results show that the landslide mode and stability of the composite slope in the south bound area of pingshuoAndaobao open-pit coal mine are mainly controlled by the safe distance between stope and dump and the weak layer of 11 coal floor. According to the design, the economic and reasonable parameters of the composite slope in the south slope shrinkage boundary area are as follows: the safe distance between the stope end side and the dump site is 50m, the width of the dump flat plate is 60m, and the working line Angle of the dump line with the abandonment height of 255m is 125°, the total discard space was95,934,100 m3.

Long-term thermal stability and settlement of heat pipe-protected highway embankment in warm permafrost regions

Warm permafrost is a challenging geological material for infrastructure engineering. This study presents the observed damage, ground temperature, and settlement at varying depths from three-year continuous monitoring of two selected highway embankment segments along the Qinghai-Tibet Highway in warm permafrost areas, including one conventional embankment and the other with heat pipes on the sunny slope side. Field monitoring data reveal that the embankment settlement mainly results from thaw consolidation of warm permafrost, and the permafrost table beneath a conventional embankment is concave-shaped due to the polythermal effects of asphalt pavement. In contrast, the permafrost table underneath the embankment equipped with heat pipes on the sunny side is convex-shaped due to heat pipes' cooling effects. The different causes of longitudinal cracks on the two embankment surfaces were uncovered based on field observed data. Results of coupled hydro-thermal-mechanical model simulation considering climate warming show that while the configurations of heat pipes on both sides of the embankment can generally ensure the long-term thermal stability and limit the differential settlement across the road surface, the one with slanted heat pipes delivers the best performance and is recommended for future applications. Results from this study, including field monitoring data and recommended heat pipe configuration, will be of value for the construction and maintenance of transportation infrastructure in warm permafrost regions.

FEM modeling and simulation of kerf formation in the nanosecond pulsed laser engraving process

In the present study, a finite element method (FEM) simulation model is developed for nanosecond pulsed laser engraving process. The model’s novelty lies in the fact that it predicts the actual dimensions of the engraved geometry emphasizing the dimensional deviation due to the defects from kerf formation such as the sloped side walls instead of the intended vertical ones. Simulations were performed and the values of kerf taper angle, top kerf width and bottom kerf width were compared with the corresponding ones from experimental tests made using a LASERTEC 40 laser engraving machine and also were used for process optimization.

DETERMINING THE EFFECT OF CHANGING CHANNEL GEOMETRY OF IRRIGATION CANALS ON DISSOLVED OXYGEN CONCENTRATION

Dissolved oxygen (DO) is an important water quality parameter. It is considered the most important parameter. DO concentration in water is affected by different parameters such as volume flow rate, water velocity, and re-aeration rate. Those parameters are directly affected by the geometry of the waterway. Thus, studying the impact of changing channel geometry on DO is very important. Many researchers studied the effect of influential parameters on water quality variables but the influence of channel geometric parameters on DO was not studied thoroughly before. This research aims to study the effect of changing channel geometry on DO concentration. The DO is modeled along the channel using Streeter-Phelps equation. Studied geometric parameters are water depth, bottom width, side-slopes, and channel length. The case study is taken as Sheikh Zayed canal in Egypt. Sheikh Zayed canal is responsible for irrigating Toshka land in the Western Desert of Egypt. It is also responsible for increasing the cultivated area of Egypt by about 550,000 feddans. It was found that the DO concentration is greatly affected by changing the geometry of the canal, as the canal geometry directly influences the flow velocity as well as reaeration rate. The percentage change of DO concentration with every geometry parameter is for length 6.8%, bed width 1.8%, water depth 4%, and side slopes 1.4%.

Stability analysis of full-section construction of staggered distance double-hole tunnel

In the staggered distance double-hole tunnel located on the slope of the mountain, the deformation of the surrounding rock and the supporting structure of the tunnel is complicated. The deformation stability of the tunnel entrance is one of the most difficult points of the tunnel. In order to clarify the deformation law of the full-section construction at the entrance of the staggered distance double-hole tunnel, the entrance section of the Georgia E60 Highway No. 3 tunnel under construction is used as the background, and the method of numerical simulation test is used to study the staggered distance double-hole tunnel, the influence of section construction on the deformation and stability of the side and front slopes of the tunnel entrance section and the support structure of the tunnel entrance section. The research results show that: For tunnels with full-section construction, excavation will cause certain deformations on the ground and the tunnel, and the stability of the left side support structure of the right line tunnel without rock column between the two tunnels is worse than that in other positions, on the whole, the construction plan is reasonable and feasible.

Laboratory Physical Modeling of Rakuna IV Armor Block Stability and Overtopping Discharge of Patimban Port’s Rubble Mound Breakwater

A series of 2D physical model experiment was carried out to examine the potential advantage of Rakuna IV armor block over Tetrapod blocks in term of stability, number of blocks for the same cross-section and overtopping discharge under predetermined experiment conditions. For the sea side slope armor, Rakuna IV – 2ton armor blocks perform advantageous stability in comparison to Tetrapod-2ton blocks for the case of Hmo= 1.2×Hs. For the harbor side slope armor and toe armor, rocks of 300-1000kg/pc performs high stability with very less damage, with S << 2 and S=0.11 respectively (S=2 is initial damage condition). For the crest elevation +2.5mCD, overtopping discharge over either Rakuna IV or Tetrapod armored slopes are more or less at the same amount and both are still within allowed criteria limit. For the crest elevation +2.1mCD, overtopping discharge over Rakuna IV is still within allowed criteria limit. Reduction of breakwater crest from +2.5mCD to +2.1mCD (Rakuna IV) has relatively increased overtopping discharge four times higher, but it is still within allowed criteria limit. For the present experimental design, Rakuna IV armor layer is requiring less number of fabricated blocks for the same cross-section compared to Tetrapod block.

NUMERICAL STUDY ON THE INFLUENCE OF SLOPE AND SNOW-FENCE ON THE FLOW FIELD AROUND EMBANKMENT

The side slope of an embankment is an important factor affecting the flow field around the embankment. A snow-fence is a common snow prevention measurement in the road blowing snow disaster. It is beneficial to improve the distribution of snow accumulation around an embankment by changing the slope of the embankment and reasonably setting up the snow-fence in the windward. The flow field characteristic of an embankment with different slopes was studied using a numerical simulation method and the snow distribution of the embankment was analyzed. On the basic of this, the snow prevention effect of the snow-fence in different rows for the embankment was studied by installing snow-fences on the windward of the embankment. The result shows that the characteristics of the flow around the embankment are closely related to the slope and the range of wind speed weakening area formed due to the flow passing through the embankment is proportional to slope. By setting snow-fences with a reasonable parameter in a legitimate position, the flow field around the embankment can be improved and the snow drifting can be weakened to come into the effect of snow prevention.

Field and numerical studies on the thermal performance of air convection embankments to protect side slopes in permafrost environments

Shoulder air convection embankments (ACEs) are sufficient to counter the effect of ground staying relatively warm due to the insulation of snow accumulation on side slopes of northern transportation infrastructure. However, little information is available for the design procedure. This paper aims to propose new design guidelines and an engineering design chart to quantify the heat extraction capacity of shoulder ACEs. The tested shoulder ACE, constructed on the Alaska Highway at Beaver Creek, Yukon, in 2008, provided valuable data for the assessment of field performance and model development. Thermistor strings were installed under the centerline and under the side slope. Measurements indicated that the cooling of ground soils was significant mainly under the side slope during the monitoring years from 2009 to 2013. The data collected were also used to calibrate a coupled conduction-convection model to reproduce the thermal conditions and the changing temperature trend in the subgrade. An engineering design chart was developed based on the calibrated model, and was successfully validated using the thermal data from the Puvirnituq airstrip in Northern Quebec, Canada.

Characterizing Geomorphology of Mesophotic Coral Reef Ecosystems in the Southwestern Gulf of Mexico: Implications for Conservation and Management

Coral reefs are the most biodiverse ecosystems on earth and are presently experiencing severe declines globally. Shallow coral reef ecosystems (&amp;lt;30 m) have been studied extensively while mesophotic coral ecosystems (MCE) are poorly studied. As a result, MCE are rarely included in marine reserve design and management, despite their ecological importance and connectivity to shallow reefs. In this study, we assessed the fine-scale topographic complexity, a proxy for structural complexity, for a group of coastal coral reefs in a marine park in the southwestern Gulf of Mexico, in depths between 2 and 49 m. We conducted hydrographic surveys using a semi-portable multibeam echosounder system to produce 3D bathymetry digital terrain models (DTM) with a 2.5 m spatial resolution for three submerged bank reefs and two emerging reefs. From these models, descriptive terrain parameters were calculated for each reef, including slope, aspect, curvature, rugosity and ruggedness. Results show that all reefs are predominantly northeast-southwest oriented, with well-defined leeward and windward sides. For the three submerged bank reefs, structural complexity increased with depth. Estimated mean ruggedness and rugosity were highest at 20–40 m depth range on windward side slopes. Emerging reefs showed high structural complexity, particularly at the 25–40 m depth range. We identified a spur and groove zone with maximum ruggedness (0.26) and rugosity (3.17) values, and four channels with steep slopes (68°) and dispersed mounds. We found that at mesophotic depths (&amp;gt;30 m), southern reefs basements from two distinct reefs merge to form a continuous complex. This has important management implications since presently, only 28.7% of this reef complex (mostly shallow areas) are within the existing limits of the marine park’s core zone. Considering the newly recognized importance of MCE, we propose expanding and reshaping the core zone to include the entire reef complex which mostly encompasses MCE with high structural complexity. Our study illustrates the value of semi-portable MBES for marine planning in developing countries and remote poorly studied areas.

Numerical analysis of pressures on rigid structures using the smoothed particle hydrodynamics method

The paper presents a numerical analysis of hydrodynamic pressures on rigid structures caused by dynamic base excitation. First, the model for the fluid simulation, based on the numerical approach called the Smoothed Particle Hydrodynamics (SPH) method, is presented. Then, the described model is used to calculate the pressures on rigid structures. In the performed analysis, the structures of various geometries (a rectangular tank with vertical sides, rectangular tanks with one inclined side of constant slope and a cylindrical tank) are exposed to simple harmonic horizontal base excitations. The obtained hydrodynamic pressures on the sides of the tanks are compared with analytical and other numerical solutions.

A Review: The Tectonic Perspective and seismic response of Darbandikhan Dam Stability and potential solutions

Darbandikhan dam is a rockfill dam constructed northwest of Iraq in the early sixties. Even though the dam is located in a mountain zone with high seismic influence, the dam was not designed to resist a high seismic motion. This study is a review of Darbandikhan dam current situation and the possible factors of its potential failure. The dam can be regarded as a vulnerable condition. Due to the unstable geologic formations and the existence of limestone and anhydrite which can impact the dam stability. On the other hand, rainfall dwindling and the temperature rising affected the hydrological system in the area. Climate change causes drought, desertification followed by a flood in a very short period. Therefore, the dam reservoir elevation has been diminished due to the reduction of the inflow. The dam has experienced a strong seismic motion in November 2017, it causes serious fissures on the dam road, failure on the left side slope and rocks toppling. The sliding of soil and the falling rocks in the dam lake when the earthquake hit the dam location, lead to clay accumulation which has prevented the gates to be opened. Serious and fast maintenance have to be implemented to fix the landslides and dam safety against earthquakes.

A Comprehensive Investigation on Abnormal Impoundment of Reservoirs—A Case Study of Qionglin Reservoir in Kinmen Island

Leakage is the most serious problem in reservoir operation, because heavy leakage influences reservoir impoundment efficiency and even leads to a complete loss of reservoir functions. Since its completion in 1982, Qionglin Reservoir has never been fully filled with water except in the spring of 1983 when there was heavy rain. The reservoir management unit suspected that its side slopes, bottom or dam might leak and carried out a number of leakage prevention and improvement works, but all of them failed to fulfill the impoundment function of the reservoir. Hence, this study attempts to find out the reasons why the reservoir cannot impound water. A series of tests and investigations are carried out in this study, including electrical resistivity tomography of dam, tracer test, geological drilling test, reservoir water level observation, investigation of reservoir catchment area and field investigation of dam. The test results and investigation results show that no leakage path and leakage are found. According to the analysis, there is no serious leakage of this reservoir. The main reason for the failure of impoundment is that massive improper development in the catchment area influences the runoff into the reservoir.

Influence of Water Temperature and Side Slope on Sand Bed Channels.(Dept.C)

A mathematical model was used to study the effect of both water temperature and side slope on sand bed channel geometry and longitudinal slope. The study has revealed no responses occurred for both mean width and water depth due to the change in water temperature over 0OC for canal having median particle size ≤ 0.5 mm. For canals having dso ≥ 0.6 mm, moan width decreased and water depth increased especially from Octo about 20 OC, Bed slopes decreased regularly with the increasing value of water temperature. Statistical analysis was used to fit this variation. Both mean width and water depth decreased and bed slope increased with the increase of the channel side slope.