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In urban areas, trees are often planted in bare soil sidewalk openings (tree pits) which recently are being covered with permeable pavements. Pavements are known to alter soil moisture and temperature, and may have implications for tree growth, root development and depth, drought resilience, and sidewalk lifting. Furthermore, tree pits are often the only unsealed soil surface and are important for water exchange between soil and atmosphere. Therefore, covering tree pits with pavement, even permeable, may have implications for the urban water balance and stormwater management. A better understanding of permeable pavement on tree pavement soil system functioning can inform improved tree pit and street design for greater sustainability of urban environments. We conducted experiments at two sites in Virginia, USA (Mountains and Coastal Plain) with different climate and soil. At each location, we constructed 24 tree pits in a completely randomized experiment with two factors: paved with resin-bound porous-permeable pavement versus unpaved, and planted with Platanus x acerifolia 'Bloodgood' versus unplanted (n = 6). We measured tree stem diameter, root growth and depth, and soil water content and temperature over two growing seasons. We also monitored tree sap flow one week in June 2017 at the Mountains. In addition, we calibrated and validated a soil water flow model, HYDRUS-1D, to predict soil water distribution for different rooting depths, soil textures and pavement thicknesses. Trees in paved tree pits grew larger, with stem diameters 29% (Mountains) and 51% (Coastal Plain) greater. Roots developed faster under pavement, possibly due to the increased soil water content and the extended root growing season (14 more days). Tree transpiration was 33% of unpaved and planted pit water outputs, while it was 64% for paved and planted pits. In June 2016, planted pits had decreased root-zone water storage, while unplanted pits showed increased storage. A water balance of the entire experimental site showed overall decreased soil water storage due to tree water extraction becoming the dominant factor. HYDRUS-1D provided overall best results for model validation at 10 cm depth from soil surface (NSE = 0.447 for planted and paved tree pits), compared to 30- and 60 cm depths. HYDRUS-1D simulations with greater pavement thickness resulted in changes in predicted soil water content at the Coastal Plain, with higher values at 10- and 30-cm depths, but lower values at 60-cm depth. At the Mountains, virtually no difference was observed, possibly due to different soil texture (sandy vs clayey). Tree pits with permeable pavement accelerated tree establishment, but promoted shallower roots, possibly increasing root-pavement conflicts and tree drought susceptibility. Paved tree pits resulted in larger trees, increasing tree transpiration, but reduced soil evaporation compared to unpaved pits. Larger bare soil pits surrounded by permeable pavement might yield the best results to improve urban stormwater retention. Also, HYDRUS 1D was successful at simulating soil water content at 10-cm depth and may be valuable to inform streetscape design and planning. / PHD / Trees in cities are often planted in pavement cutouts (tree pits) that are usually the only available area for water exchange between soil and atmosphere. Tree pits are typically covered with a variety of materials, including permeable pavement. Pavements are known to modify soil water distribution and temperature, affecting tree growth, rooting depth, drought resilience, and sidewalk lifting. A better understanding of this system can inform tree pit and street design for greater sustainability. We constructed 24 tree pits at each of two regions in Virginia, USA (Mountains and Coastal Plain). These tree pits were paved with permeable pavement or unpaved, and planted with London Plane or unplanted. We measured stem diameter, root growth, and soil water content and temperature over two years and tree sap flow for one week in summer (Mountains only). We also used a soil water flow model, HYDRUS-1D, to predict water distribution for different rooting depths, soil textures and pavement thicknesses. After the first growing season trees in pavement were larger, with stem diameters 29% (Mountains) and 51% (Coastal Plain) greater. Roots developed faster under pavement, possibly due to increased soil water content and a 14-day increase in root growing season. Also, in June 2017, tree transpiration was 33% of unpaved-and-planted pit water outputs, and 64% of paved-and-planted pits. In June 2016, root-zone water storage decreased in planted pits but increased in unplanted pits. When considering the entire experimental site, soil water storage decreased, with tree water extraction being the dominant factor. HYDRUS-1D performed better at 10-cm soil depth than at 30- and 60-cm depths. At the Coastal Plain, HYDRUS-1D predicted higher soil water content at 10- and 30-cm depths with increased pavement thickness, but lower values at 60-cm depth. At the Mountains, there was no effect, possibly due to higher clay content. Permeable pavement accelerated tree establishment, but promoted shallower roots, increasing drought susceptibility and risk for root-pavement conflicts. Pavement resulted in larger trees and greater transpiration, but reduced soil evaporation. Larger bare-soil pits surrounded by permeable pavement might optimize stormwater retention.

Магистерская диссертация посвящена проектированию завода по производству стеновых блоков из легкого бетона на основе безобжигового зольного гравия. Проведен эксперимент по получению безобжигового зольного гравия из золы-унос Рефтинской ГРЭС (Свердловская область, РФ). Получен БЗГ, обладающий маркой по плотности М900 для гранул после нормального твердения и маркой М1000 для гранул после пропаривания. Марка по прочности – П250. Полученный БЗГ соответствует требованиям ГОСТ 32496–2013. Получен облегченный бетон на БЗГ класса В12,5. Разработана технологическая схема и подобрано основное оборудование для производства БЗГ. Для производства стеновых блоков выбран агрегатно-поточный способ производства. Составлена технологическая схема, определено количество постов. Рассчитано и подобрано основное и вспомогательное оборудование: для обеспечения работы каждой из четырех линии нужно 65 форм, ямная камера размерами 8,0х4,7х2,9 м, бетоноукладчик СМЖ-859, вибротумба СМЖ-200, рельсовая механизированная тележка СМЖ-151 и мостовой кран грузоподъёмностью 10 т. Рассчитан склад готовой продукции: 30 х 36 м. Определен список и численность работников формовочного цеха. Выполнена графическая часть. / The master's thesis is devoted to the design of a plant for the production of wall blocks made of lightweight concrete based on non-burnt fly ash gravel. An experiment was conducted to obtain non-burnt fly ash gravel from fly ash from Reftinskaya GRES (Sverdlovsk region, Russian Federation). NBFAG was obtained, which has a density mark M900 for granules after normal hardening and a mark M1000 for granules after steaming. The strength grade is P250. The resulting NBFAG complies with the requirements of GOST 32496-2013. Lightweight concrete was obtained for NBFAG of class B12.5. A technological scheme has been developed and the main equipment for the production of NBFAG has been selected. An equipment-flow production method has been selected for the production of wall blocks. A technological scheme has been drawn up, the number of posts has been determined. The main and auxiliary equipment was calculated and selected: to ensure the operation of each of the four lines, 65 forms are needed, a pit chamber with dimensions of 8.0x4.7x2.9 m, a concrete paver SMJ-859, a vibrating column SMJ-200, a rail mechanized trolley SMJ-151 and an overhead crane with a lifting capacity of 10 tons. The warehouse of finished products is designed: 30 x 36 m. The list and number of employees of the molding shop have been determined. The graphic part is completed.

En rivière à lit de graviers, le transport des sédiments en charge de fond est un processus intermittent qui dépend de plusieurs variables du système fluvial dont la prédiction est encore aujourd’hui inexacte. Les modèles disponibles pour prédire le transport par charriage utilisent des variables d’écoulement moyen et la turbulence n’est généralement pas considérée malgré que les tourbillons contenus dans les écoulements possèdent une quantité d’énergie importante. L’utilisation de nouvelles approches pour étudier la problématique du transport par charriage pourrait nous permettre d’améliorer notre connaissance de ce processus déterminant en rivière alluviale. Dans ce mémoire, nous documentons ces composantes de la dynamique fluviale dans un cours d’eau graveleux en période de crue. Les objectifs du projet de recherche sont : 1) d’examiner l’effet du débit sur les variables turbulentes et les caractéristiques des structures turbulentes cohérentes, 2) d’investiguer l’effet du débit sur les caractéristiques des événements de transport de sédiments individuels détectés à l’aide d’un nouvel algorithme développé et testé et 3) de relier les caractéristiques de l’écoulement turbulent aux événements de transport de sédiments individuels. Les données de turbulence montrent qu’à haut niveau d’eau, l’écoulement décéléré est peu cohérent et a une turbulence plus isotrope où les structures turbulentes cohérentes sont de courte durée. Ces observations se distinguent de celles faites à faible niveau d’eau, en écoulement accéléré, où la plus grande cohérence de l’écoulement correspond à ce qui est généralement observé dans les écoulements uniformes en rivières graveleuses. Les distributions de fréquence des variables associées aux événements de transport individuel (intensité de transport moyenne, durée d’événement et intervalle entre événements successifs) ont des formes différentes pour chaque intensité de crue. À haut niveau d’eau, le transport est moins intermittent qu’à faible débit où les événements rares caractérisent davantage les distributions. L’accélération de l’écoulement à petite échelle de temps joue un rôle positif sur le transport, mais surtout lorsque la magnitude de la crue mobilisatrice est en dessous du niveau plein bord. Les résultats de l’étude montrent que les caractéristiques de la turbulence ainsi que les liens complexes entre l’écoulement et le transport par charriage sont fonction du débit. / In gravel-bed rivers, bedload transport is an intermittent process related to many variables of the fluvial system whose prediction is still unreliable. Available models for prediction of bedload transport use mean hydraulics variables and generally do not consider turbulence even if coherent turbulent flow structures in rivers are highly energetic. New approaches to bedload transport investigation can shed light on this very important process in alluvial channels. In this thesis, we document these components of the fluvial system in a gravel-bed river during a flood. The objectives of the research are to: 1) investigate the effect of discharge on turbulent variables and turbulent coherent flow structures, 2) investigate the effect of discharge on bedload transport events statistics detected with a newly developed and tested algorithm and 3) link turbulent flow characteristics to individual bedload transport events. Turbulence data shows that at high water level, the decelerated flow has a low coherency and an isotropic turbulence where coherent turbulent flow structures have a short duration. These observations differ from those made at low water level where the accelerated flow corresponds to what is generally observed in uniform flows of gravelly channels. Frequency distributions of bedload transport events variables (mean bedload transport rate, event duration and time interval between successive bedload events) have different shapes for the two investigated flood intensity. At high water level, bedload transport is less intermittent that at low discharge where distributions are more characterised by rare events. Flow velocity acceleration on a short time scale has a positive effect on bedload transport, but mainly when the mobilizing flood is under bankfull stage. Results from the study show that turbulence properties and complex relationships between turbulence and bedload transport are a function of discharge.

Approximately 75 percent (300 000 km) of the total Swedish road network and 20 percent(20 000 km) of the national road network consists of gravel roads. One of the most significantproblems associated with gravel roads is traffic-generated dust emission, which contributes tothe deterioration of the road surface and acts as a major source of particulate matter releasedinto the atmosphere, thereby involving public economics, road safety, human health, andenvironmental quality. In order to bind the fine granular material, which is prone to rise into theair, dust suppressants are applied on roads on a yearly basis. Methods for evaluating the efficiency of dust suppressants will facilitate in the selection of themost appropriate product and its optimal application rate. For example, methods forsupervision of residual dust suppressant concentration are valuable tools for estimatinglongevity and optimal application rates, and, consequently, effectiveness of different products. Application of the proper dust suppressant to a gravel road ensures road safety and ridingcomfort as well as creating a cleaner and healthier environment for residents in buildingsadjacent to the road. It also reduces the need and cost for vehicle repair, road maintenanceactivities, and aggregate supplementation. Both field-based and laboratory research were performed to evaluate the efficiency of varioussuppressants and the influence such factors as product concentration, leaching, and fine materialcontent have on the efficiency of different products. Within the field-based research, a newlydeveloped mobile methodology was used to measure dust emission on numerous test sectionstreated with various dust suppressants. In general, all dust suppressants tested, except apolysaccharide (sugar) and products, which form a brittle surface crust, i.e. lignosulphonate andbitumen emulsion, showed acceptable dust reduction. Test sections treated with a magnesium- or calcium chloride solution were the most effectivelydust suppressed. The application of solutions instead of a solid salts achieves a more uniformproduct distribution and, therefore, probably a more efficient performance. By applying acalcium- or magnesium chloride solution instead of traditionally used solids, the cost for annualdust control, as well as the environmental impact from the release of these chemicals in theenvironment, can be reduced by 50 percent. A significant problem when using dust suppressants is their tendency to leach during rainfalldue to their soluble properties. Residual chloride could be detected in the gravel wearing courseover a longer period of time than lignosulphonate and, therefore, showed more effective longtermperformance. Optimal percentages of fine material for minimal lignosulphonate andchloride leaching were found to be 15 percent by weight and 10-16 percent by weight,respectively. Ions of calcium chloride seemed to initiate flocculation of clay particles, therebypreventing them from leaching. Still, the fine material in gravel wearing courses has to be replenished regularly as indicated by studies of the longevity of fine material. Loss up to80 percent was found after two years. Toxicity tests show that dust suppressant application for dust control purposes, at traditionallyused application rates, does not constitute a threat to sensitive aquatic life. Tests on subsoilwater samples indicated elevated chloride levels, which possibly could cause corrosion to pipes,but not high enough to flavour drinking water. / QC20100616

En rivière à lit de graviers, le transport des sédiments en charge de fond est un processus intermittent qui dépend de plusieurs variables du système fluvial dont la prédiction est encore aujourd’hui inexacte. Les modèles disponibles pour prédire le transport par charriage utilisent des variables d’écoulement moyen et la turbulence n’est généralement pas considérée malgré que les tourbillons contenus dans les écoulements possèdent une quantité d’énergie importante. L’utilisation de nouvelles approches pour étudier la problématique du transport par charriage pourrait nous permettre d’améliorer notre connaissance de ce processus déterminant en rivière alluviale. Dans ce mémoire, nous documentons ces composantes de la dynamique fluviale dans un cours d’eau graveleux en période de crue. Les objectifs du projet de recherche sont : 1) d’examiner l’effet du débit sur les variables turbulentes et les caractéristiques des structures turbulentes cohérentes, 2) d’investiguer l’effet du débit sur les caractéristiques des événements de transport de sédiments individuels détectés à l’aide d’un nouvel algorithme développé et testé et 3) de relier les caractéristiques de l’écoulement turbulent aux événements de transport de sédiments individuels. Les données de turbulence montrent qu’à haut niveau d’eau, l’écoulement décéléré est peu cohérent et a une turbulence plus isotrope où les structures turbulentes cohérentes sont de courte durée. Ces observations se distinguent de celles faites à faible niveau d’eau, en écoulement accéléré, où la plus grande cohérence de l’écoulement correspond à ce qui est généralement observé dans les écoulements uniformes en rivières graveleuses. Les distributions de fréquence des variables associées aux événements de transport individuel (intensité de transport moyenne, durée d’événement et intervalle entre événements successifs) ont des formes différentes pour chaque intensité de crue. À haut niveau d’eau, le transport est moins intermittent qu’à faible débit où les événements rares caractérisent davantage les distributions. L’accélération de l’écoulement à petite échelle de temps joue un rôle positif sur le transport, mais surtout lorsque la magnitude de la crue mobilisatrice est en dessous du niveau plein bord. Les résultats de l’étude montrent que les caractéristiques de la turbulence ainsi que les liens complexes entre l’écoulement et le transport par charriage sont fonction du débit. / In gravel-bed rivers, bedload transport is an intermittent process related to many variables of the fluvial system whose prediction is still unreliable. Available models for prediction of bedload transport use mean hydraulics variables and generally do not consider turbulence even if coherent turbulent flow structures in rivers are highly energetic. New approaches to bedload transport investigation can shed light on this very important process in alluvial channels. In this thesis, we document these components of the fluvial system in a gravel-bed river during a flood. The objectives of the research are to: 1) investigate the effect of discharge on turbulent variables and turbulent coherent flow structures, 2) investigate the effect of discharge on bedload transport events statistics detected with a newly developed and tested algorithm and 3) link turbulent flow characteristics to individual bedload transport events. Turbulence data shows that at high water level, the decelerated flow has a low coherency and an isotropic turbulence where coherent turbulent flow structures have a short duration. These observations differ from those made at low water level where the accelerated flow corresponds to what is generally observed in uniform flows of gravelly channels. Frequency distributions of bedload transport events variables (mean bedload transport rate, event duration and time interval between successive bedload events) have different shapes for the two investigated flood intensity. At high water level, bedload transport is less intermittent that at low discharge where distributions are more characterised by rare events. Flow velocity acceleration on a short time scale has a positive effect on bedload transport, but mainly when the mobilizing flood is under bankfull stage. Results from the study show that turbulence properties and complex relationships between turbulence and bedload transport are a function of discharge.

Esta Tesis de investigación estudia la propuesta de aplicación de un sistema de mejoramiento de suelos para un proyecto inmobiliario de nueve niveles que se proyecta ejecutar en el distrito de San Juan Bautista, en la región Loreto, la cual colinda con el distrito de Iquitos. Bajo esta premisa, se desarrolla la idea de cómo introducir un sistema de mejoramiento para suelos de baja resistencia, el cual reemplazará el sistema de cimentaciones profundas propuesto inicialmente, en el terreno del proyecto se realizó el estudio de suelos y se concluyó que las capas superficiales son de material orgánico, en la capa intermedia con alta potencia se clasifico a las arenas y finalmente se encontró arcilla dura a una profundidad promedio de 8 a 9 metros. A continuación se procedió a estudiar conceptualmente los diferentes tipos de cimentación profunda y sistemas de reforzamiento de suelos. Finalmente nos centramos en el sistema de Pilas de grava compactada, la cual ya registra eficientes antecedentes en diversos proyectos realizados en la ciudad de Lima, y en el norte del país. Es así, que debido a las características desfavorables de los suelos de la ciudad de San Juan Bautista, se optó a dar inicio con la realización del diseño, luego a la evaluación del proceso constructivo, el análisis de los recursos a emplear; siendo la etapa de exploración de canteras, el proceso más determinante para el inicio de la viabilidad del sistema en términos de diseño, costo y tiempo de ejecución. Finalmente se concluye que el sistema de Pilas de grava compactada tiene la capacidad de incrementar la presión admisible del suelo, y disminuir los costos de construcción de la cimentación. / This Research Thesis studies the proposal for the application of a soil improvement system for a nine-level real estate project that is planned to be executed in the San Juan Bautista district, in the Loreto region, which borders the Iquitos district. Under this premise, the idea of how to introduce an improvement system for highly compressible soils is developed, which will replace the system of deep foundations initially proposed, in the field of the project the soil study was carried out and it was concluded that the surface layers are of organic material, in the intermediate layer with high power the sands were classified and finally hard clay was found at an average depth of 8 to 9 meters. Next, the different types of deep foundations and soil reinforcement systems were conceptually studied. Finally, we focus on the system of Piles of compacted gravel, which already records efficient records in various projects carried out in the city of Lima, and in the north of the country. Thus, due to the unfavorable characteristics of the soils of the city of San Juan Bautista, it was decided to begin with the realization of the design, then to the evaluation of the construction process, the analysis of the resources to be used; being the quarry exploration stage, the most decisive process for the beginning of the viability of the system in terms of design, cost and execution time. Finally, it is concluded that the system of compacted gravel piles has the capacity to increase the admissible pressure of the soil, and decrease the construction costs of the foundation / Tesis

This study aimed to evaluate the ecological impacts of sand mining on the Mokolo River, in Lephalale. The study focused on the water quality, macroinvertebrates and physical disturbances as indicators in order to determine the ecological im-pacts of sand mining on the Mokolo River. The water quality variables, which this study entailed, were related to sand mining and other sources of pollution such as coal mining, power station industries, agriculture and wastewater treatment works on the Mokolo River. The water quality results for pH, electrical conductivity (EC), total alkalinity (CaCO3), sodium (Na), calcium (Ca), magnesium (Mg), potassium (K), chloride (Cl), fluoride (F), sulphate (SO4) and nitrate (NO3-N) were not over the limits, however turbidity, total coliforms and E. coli were over the limits as per the Target Water Quality Guideline (TWQG). The River Health Programme (RHP) was done at upstream, sand mining and downstream areas in the Mokolo River using the South African Scoring System Version 5 (SASS5). The ecological status at the upstream and downstream areas changed from class C (March 2018) to class B (November 2018), indicating that the ecological status improved in those areas of the Mokolo River. However, at the sand mining area the ecological status has not improved and it was seriously modified due to the physical disturbance as a result of sand mining. Ecological impacts, such as the removal of marginal and riparian vegetation, erosion, disturbed riverbed, undercutting and collapse of riverbanks, loss of adjacent land, river deepened, river widened, water pools, in stream sand stockpiles and river diversions, were determined at the sand mining area. No physical disturbances at the upstream and downstream areas were determined. The findings of this study indicate that the ecological impacts of change in water quality at the upstream and downstream areas was due to high turbidity, Total coli-forms and E. coli. The absence of sensitive macroinvertebrates and loss of ma-croinvertebrates and the physical disturbances within the Mokolo River was be-cause of sand mining. The study indicates that sand mining has negative impacts on the water quality, water quantity, macroinvertebrates and physical characteris-tics of the Mokolo River. / Environmental Sciences / M. Sc. (Environmental Science)

The aim of the diploma thesis is to elaborate a selected part of the construction technology plan for the Residential complex Troubsko. Specifically, it is focused on a pair of mirror-image apartment buildings marked SO 12.11 and SO 12.12. The building is located in the area of a former pond, which was backfilled in the past. The foundation strips are therefore placed on vibrated gravel pillars. The structure of the building is proposed as a traditional masonry building, the horizontal load-bearing structures consists of the cast-in-place reinforced concrete floor and the roof structure is designed as a flat roof. The thesis consists in a technical report pertaining to the construction technology plan, evaluation of transport routes, technological regulation for the cast-in-place reinforced concrete floor above 1PP and a time schedule for rough construction. Also elaborated are construction site equipment including a drawing and text part, a control and test plan, itemized budget with bill of quantities for rough construction, design of machine sets and work safety solutions are elaborated.

The content of this bachelor work is the project documentation of the hotel On the View in Nový Hradec Králové. The build has three ground floors, without partial basement and it is roofed by flat roof with pea gravel. A build has 2 parts. First part si for guests and second part is for employees. The build has 2 entrance. In the first floor is reception with facility, toilet, restaurant with kitchen, food warehouses, untility room and background for employees. From a restaurant is access to the terrace. In the second and third floor are rooms for 34 guests (of which 2 for handicapped) and background for cleaning women. A Hotel has car park for guests with 13 places ( of which 2 fort handicapped) and car park for employees with 4 places. The construction system is mostly made of polished ceramic blocks Porotherm. Horizontal construction is made up as Porotherm ceiling with brick inserts MIAKO and ceramic-concrete ceiling beams. Part of the proposal is thermal engineering assessment, fire safety solutions and assessments in terms of acoustic and daylight.