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Researching rapid multiplication techniques for mosaic-resistant cassava in tunnel greenhouses is crucial for ensuring food security and sustainable agriculture. Our previous findings indicated that a combination of 50% shading and 70-75% humidity significantly enhanced the formation of shoots and growth of cassava seedlings in a tunnel greenhouse. The current study examines the impact of different substrate compositions on cassava propagation. The experiments were designed as split plots with three replicates and four formulas including CTRL: 100% sand with a thickness of 40 cm; CT-1: 100% sand with a thickness of 30 cm; CT-2: 60% sand and 40% gravel with a thickness of 40 cm; CT-3: 70% sand and 30% gravel with a thickness of 40 cm; and CT-4: 50% sand and 50% gravel with a thickness of 40 cm. The results demonstrated that CT-3 yielded the highest shoot formation rate and growth of cassava seedlings, suggesting that the combination of sand (70%) and gravel (30%) at a thickness of 40 cm provide the most favorable conditions for cassava propagation in tunnel greenhouse conditions. [ABSTRACT FROM AUTHOR]

Copyright of Industrial Minerals & Processing / Huagong Kuangwu yu Jiagong is the property of Industrial Minerals & Processing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A two-dimensional sand tank model was designed to investigate the water distribution and sediment clogging of the Yellow River water during the seepage recharge process of the piedmont sand gravel channel in the North China Plain. Due to the high permeability of the sand gravel medium, only infiltration deep runoff (IDR) and surface runoff (SR) occurred in the sand tank experiment. The increase in water released did not improve the effective recharge. The IDR accounted for 65–85% of the water released. After clogging appeared, the value decreased to 15–30%. More than 96% of suspended solids were deposited in the surface and upper areas of the sand tank, among which the sand gravel surface covered by the thin clay layer formed by suspended particles was the main cause of the change in the distribution of IDR and SR. A rubber dam can promote the conversion of high velocity SR to low velocity lateral shallow runoff (LSR) by 25–30% while increasing the deposition mass of suspended particles in the sand tank. The rationality of the sand tank model was verified by the numerical model, and the fitting degree between the simulated and the measured results was greater than 0.9. HIGHLIGHTS Only infiltration deep runoff and surface runoff appear during recharging of the piedmont sand gravel channel.; The suspended solids concentration and the medium infiltration capacity have a major effect on water and sediment movement processes in the recharging.; The rubber dam built on the riverbed surface can promote the conversion of surface runoff to lateral shallow runoff.;

Crushed rock fragments are usually a mixture of particles with different sizes and morphologies comprising particle shape and surface texture scales. The significant role of particle morphology in the engineering behavior of granular materials has been increasingly appreciated. However, studies on morphology are mainly on particles of similar sizes, and the few studies that reported particles with varying sizes are limited to particle shape scale alone, especially when 3D morphological characteristics are considered. In this paper, we investigate the multi-scale morphological characteristics of crushed rock with a size ranging from sand to gravel by employing a 3D laser scanner and micro-Computed Tomography (μCT) using quantifiers of sphericity, aspect ratio, and roundness for particle shape, and fractal dimension for surface texture. Crushed granitic rock is used as the testing material to elucidate the morphological characteristics of crushed materials, which are not uncommon in geotechnical applications. For the tested crushed granitic rock, as particle size decreases, the overall shape becomes slightly angular, the corner of the particle becomes more rounded, and the surface becomes smoother. Differences in the morphological descriptors for small particles, mainly those with singular mineral composition, have also been observed and might be explained in terms of hardness and fracture features. The observed dependence of morphological descriptors on particle size and mineralogy bears significance for investigations using reconstructed particles of different sizes using 3D-printing techniques and numerical methods. [ABSTRACT FROM AUTHOR]

In this paper, an improved method of sand and mud content detection for concrete is proposed, and a set of sand and mud content detection device for concrete is designed. In this paper, a concrete gas content meter and a bubble parameter analysis system were used to study the effect of sand clay content on the gas content of commercial concrete, the loss rate of gas content in warp time, the bubble spacing coefficient and the distribution of hardened appearance pores. The pore structure test shows that the increase of mud content will appropriately reduce the proportion of harmless pores in machine-made sand concrete, and play a role in refining the pore structure in machine-made sand concrete. By using PLC controller and automatic detection device of liquid level and turbidity, the problems of complicated operation, inconvenient carrying and poor repeatability of test data are solved. It reduces the influence of human operation error and improves the accuracy of test data.

Rivers provide important sediment inputs to many littoral cells, thereby replenishing sand and gravel of beaches around the world. However, there is limited information about the patterns and processes of littoral-grade sediment transfer from rivers into coastal systems. Here I address these information gaps by examining topographic and bathymetric data of river mouths and constructing sediment budgets to characterize time-dependent patterns of onshore, offshore, and alongshore transport. Two river deltas, which differ in their morphology, were used in this study: the Elwha River, Washington, which builds a mixed sediment Gilbert-style delta, and the Santa Clara River, California, which builds a cross-shore dispersed sand delta from hyperpycnal flows. During and after sediment discharge events, both systems exhibited a similar evolution composed of three phases: (i) submarine delta growth during offshore transport of river sediment, (ii) onshore-dominated transport from the submarine delta to a subaerial river mouth berm, and (iii) longshore-dominated transport away from the river mouth following subaerial berm development. Although stage (ii) occurred within days to weeks for the systems studied and was associated with the greatest rates of net erosion and deposition, onshore transport of sediment from submarine deposit to the beach persisted for years following the river discharge event. These morphodynamics were similar to simple equilibrium profile concepts that were modified with an onshore-dominated cross-shore transport rule. Additionally, both study sites revealed that littoral-grade sediment was initially exported to depths beyond the active littoral cell (i.e., below the depth of closure) during the stage (i). Following several years of reworking by coastal processes, bathymetric surveys suggested that 14 and 46% of the original volume of littoral-grade sediment discharged by the Santa Clara and Elwha Rivers, respectively, continued to be below the depth of closure. Combined, this suggests that integration of river sediment into a littoral cell can be a multi-year process and that the full volume of littoral-grade sediment discharged by small rivers may not be integrated into littoral cells because of sand and gravel “losses” to the continental shelf.

Extraction of mineral raw materials is increasing due to economic development and must be a normal process under due control and environmental supervision. However, there are a number of sites where the exploitation was stopped and mining sites were abandoned without proper restoration. Also, there are sites where mineral resources were or are extracted illegally thus making significant damage to the environment and economy. In order to collect information on land impacted by mining and extraction activities, for the first time a special project was carried out for the entire territory of Lithuania. The project consisted of gathering of information on damaged areas from various sources, field surveys and systematization of collected data. In order to obtain volumetric data, a special technology of aerial photogrammetry was developed and successfully applied. It was detected that the number of damaged sites > 0.3 ha reached up to 3,300. It is estimated that a total amount of illegally extracted minerals in last 15-20 years could be up to 15 million m3. The aerial photogrammetry was proved as a relevant technology and this could be applied for the control of the restoration of damaged land as well as for the monitoring of hazardous geological processes, e.g. coastal erosion, karst. [ABSTRACT FROM AUTHOR]

Substantial volumes of sediment are moved on coarse grained beaches through the formation and destruction of beach cusps, yet the processes governing cusp behaviour remain poorly understood. Here, we combine continuous 2D LiDAR scan data with daily UAV topographic surveys and RGB imagery to provide detailed morphological measurements of beach cusps on a composite beach with the aim to investigate the role of sediment size and tidal stage on cusp behaviour. Rapid changes in cusp height and prominence were observed when storm-eroded gravels were readily transported over relatively impermeable sandy substratum, showing the high-order control that mixed matrix sediments have on this process. Post storm, gravels armoured the swash zone overlaying the sand and were rapidly reworked into horns, with the incipient bays simultaneously experiencing erosion. We provide some of the first field observations to show divergent behaviours occurring simultaneously along the beach as cusps adjust to the new dominant hydrodynamic regime, with some areas experiencing a shortening of cusp wavelength through new horn growth, whilst others contemporaneously experienced wavelength growth through the removal of intermediate horns. Cusp formation was generally more pronounced on the falling tide, but some evidence indicates horns can also be consolidated and grow in relief at some stages of individual rising tides. This research demonstrates how feedback between sediments, morphology and hydrodynamics are key to determining cusp form, with these insights only made possible through the novel combination of LiDAR, UAV, and camera methods to provide sufficient temporal and spatial resolution to resolve key processes. • Mobility of coarse sediment controls timescales of beach cusp formation. • Cusp spacing adjustment occurs through divergent behaviours alongshore. • Cusp formation is irregular due to feedbacks between flow, morphology, and sediment. • Cusp growth achieved through contemporaneous horn accretion and bay erosion. [ABSTRACT FROM AUTHOR]

Copyright of Natural Gas Geoscience is the property of Natural Gas Geoscience and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

When fine sediments are present in gravel streambeds (gravel-framework beds), the gravel can be more easily removed from its original position, compared with gravel in a streambed without fine sediment but otherwise under the same hydraulic conditions. In this study, the effect of the presence of sand on the initiation of gravel motion in gravel riverbeds was investigated using flume experiments. The relationship between the critical Shields stress for gravel motion initiation and the fraction of sand in the bed was determined experimentally. The results can be summarized as follows. (1) When the fraction of sand in the bed is smaller than about 0.4, the critical Shields stress for the initiation of gravel motion decreases with increasing fraction of sand. The critical Shields stress increases, however, with increasing fraction of sand when it is larger than about 0.4. (2) The difference between the value of the critical Shields stress predicted by the Egiazaroff equation and the value obtained from the experimental data becomes maximum at about 0.4 of the fraction of sand. Here an empirical relation between the critical Shields stress and the fraction of sand is proposed so as to consider the effects of the ratio of the characteristic gravel size to the mean size of the bed material on the critical Shields stress. (3) Gravel in armored beds can be more easily mobilized by supplying sand as part of a sediment augmentation scheme. The sand fraction in the subsurface layer of the bed appears to reduce the friction angle of exposed particles. Sediment augmentation using sand has been recently demonstrated to be a viable alternative for mobilizing gravel for the restoration of gravel-bed rivers downstream of dams. The quantitative evaluation obtained through the experiments reported here may be useful for the design of augmentation schemes. Copyright © 2017 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Copyright of BHM Berg- und Hüttenmännische Monatshefte is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Příspěvek se zabývá problematikou financování technologických investic. Konkrétně jde o proces nakládání a dopravy štěrkopísků. Výzkum byl proveden formou dotazníkového šetření. Hlavním cílem příspěvku je zjistit, z jakých zdrojů je financován proces nakládání a dopravy štěrkopísků ve vybraných podnicích. Dalším cílem bylo vyhodnotit, zda vybrané průmyslové podniky outsourcují proces nakládání a dopravy. Pokud ano, pak bylo zapotřebí zjistit, jaký je nejčastější důvod takového rozhodnutí. Problematika financování technologických procesů při nakládání a dopravě štěrkopísků představuje zajímavou oblast, která doposud nebyla zmapována.

The beaches are complex systems that can be studied from different points of view and meet more than a mission to protect the coast. Their management consists of assigning solutions to problems and for this to be correct all factors involved have to be taken into account. In order to understand how management is done on the coast of the province of Alicante, surveys have been conducted among the managers of the 19 coastal municipalities of Alicante coast, covering the 91 beaches. The aim of the surveys is to try to know the problems and situations relating to the management, depending on different factors such as the level of urbanization and type of sediment. In addition, it has been investigated whether this management is aimed to protect the coastline, maintain the flora and fauna or is just a recreational management since the main economic activity is tourism. The beaches are conceived of as products offered to the user, which is what most concerns its economic importance in an area where the sun and beach tourism has a special share of the GDP. The ignorance as to the major problems regarding their physical functioning and the inability to solve them is due to a complex administrative system with which the coastal system is regulated inefficiently. The integral approach is essential for a complete and effective management of the coastal environment. [ABSTRACT FROM AUTHOR]

The City of Belgrade is the largest market for aggregates in Serbia but the production of natural aggregates is rather small, around five percent of total consumption. This reflects the geology of the City of Belgrade territory, dominated by Neogene and Quaternary sedimentary rocks. The production of crushed rock and sand and gravel on the territory of Belgrade was almost equal, while majority of imported aggregates is sand and gravel due to lower price. Consumption of crushed rocks includes around 90% of limestone and dolomite, the rest being magmatic rocks. The main issue of using crushed rock on the territory of the City of Belgrade is the long transport routes, which are usually near or more than 100 km, creating more logistic problems and increasing cost of aggregates Therefore it is necessary to establish a good supply system with low socio-environmental impact of aggregate production and transport, and the basis for that is the analysis of actual structure of production and supply of natural aggregates and new potential quarries and/or sand and gravel pits. [ABSTRACT FROM AUTHOR]

Abstract: We describe the application of 3D electrical resistivity tomography (ERT) to the characterisation and reserve estimation of an economic fluvial sand and gravel deposit. Due to the smoothness constraints used to regularise the inversion, it can be difficult to accurately determine the geometry of sharp interfaces. We have therefore considered two approaches to interface detection that we have applied to the 3D ERT results in an attempt to provide an accurate and objective assessment of the bedrock surface elevation. The first is a gradient-based approach, in which the steepest gradient of the vertical resistivity profile is assumed to correspond to the elevation of the mineral/bedrock interface. The second method uses an intrusive sample point to identify the interface resistivity at a location within the model, from which an iso-resistivity surface is identified that is assumed to define the interface. Validation of these methods has been achieved through direct comparison with observed bedrock surface elevations that were measured using real-time-kinematic GPS subsequent to the 3D ERT survey when quarrying exposed the bedrock surface. The gradient-based edge detector severely underestimated the depth to bedrock in this case, whereas the interface resistivity method produced bedrock surface elevations that were in close agreement with the GPS-derived surface. The failure of the gradient-based method is attributed to insufficient model sensitivity in the region of the bedrock surface, whereas the success of the interface resistivity method is a consequence of the homogeneity of the mineral and bedrock, resulting in a consistent interface resistivity. These results highlight the need for some intrusive data for model validation and for edge detection approaches to be chosen on the basis of local geological conditions. [Copyright &y& Elsevier]

This paper presents the results of the studies undertaken to assess the geotechnical parameters of the Torino subsoil (Italy). The ground conditions are characterized by a sand and gravel deposit, ranging from medium to highly dense, down to a depth of 8 to 10 m, and cemented soil (in cases a conglomerate), due to calcareous deposition processes, below this depth. The random distribution of cementation in the ground is a key factor in design and construction of underground works. To assess the ground properties as a function of the cementation degree, continuum and discontinuum numerical modelling were used. These were closely linked to the results of the characterization studies carried out so far in the laboratory and in the field (monitored drilling, SPT, large diameter pits, plate loading tests). In diesem Artikel werden die Ergebnisse mehrerer Untersuchungen der geotechnischen Parameter des Turiner Untergrunds (Italien) vorgestellt. Der Turiner Boden zeichnet sich durch eine mitteldicht- bis dichtgelagerte Sand- und Kiesablagerung aus, die in einer Tiefe von 8 bis 10 m ansteht; darunter liegt zementierter Boden (in einigen Fällen als Konglomerat), der auf Kalkablagerungsprozesse zurückzuführen ist. Die zufällige Verteilung der Bodenzementierung ist einer der wesentlichen Faktoren, die die Bemessung und die Durchführung von unterirdischen Bauvorhaben beeinflusst. Um die Charakteristika des Bodens in Abhängigkeit vom Zementierungsgrad zu untersuchen, wurden kontinuums- und diskontinuumsmechanische numerische Modellierungen durchgeführt. Diese Modelle stehen in direktem Zusammenhang mit den Ergebnissen von Versuchsreihen, die bis dahin im Labor und in situ ausgearbeitet wurden (Bohraufzeichnungen, SPT, großflächige Schürfe, Plattendruckversuche). [ABSTRACT FROM AUTHOR]

• China's aggregate inflow and stock markedly increased from 1978 to 2018. • The aggregate inflow reached a plateau in 2014. • The major consuming sectors shifted from buildings to infrastructure. • As a supply source, the trend has shifted from natural aggregates to manufactured ones. • Inflows and stocks have relatively decoupled from economic growth since reform and opening up. Aggregates are the most extracted material resources by weight worldwide. As an important resource for buildings and infrastructure, aggregates, however, are now facing shortages and are associated with negative environmental and social impacts. More attention is now paid to the sand and gravel issues, however, recent investigations are often found ambiguous in definition or adopting over-simplified accounting methodology. To bridge the knowledge gap, first, we conducted a detailed literature investigation to clarify the associated terms. Then we established a systematic material flow and stock accounting framework to map the social metabolism of aggregate resources for the largest aggregates consumer and producer—China. Our results show during 1978–2018, the inflows of China's aggregates increased by 13 times (1.3 to 17.3 billion tons) and the stocks increased by 15 times (18.3 to 285.5 billion tons). We observed both aggregate inflows and stocks have shown a relative decoupling from economic growth. Around 2014, inflows entered a platform area and the dominated consuming sector shifted from buildings to infrastructure. Due to supply shortages and policy interventions, the source of primary supply sees a sustainable transition: manufactured aggregates (instead of natural aggregates) gradually dominated, accounting for 78% of the total primary supply in 2018. Additionally, regarding accumulated stocks of aggregates, it is expected to see rapid growth of aggregate waste in the near future. It is essential to foster a well-functioned circular system to achieve the sustainable development of the aggregate industry. [ABSTRACT FROM AUTHOR]

Abstract: This paper uses the results of a series of sand and gravel resource assessment surveys to refine and improve the methods used for identifying aggregate resources in north-western Britain. Geomorphological surveys of the Cors Geirch and Rhosesmor areas of north Wales and the lower Ribble valley in Lancashire, carried out by 1:10,000 scale field mapping, are compared to resource assessments made using high resolution Digital Elevation Models (DEMs) of the same ground. The DEMs proved useful tools for remote geomorphological survey, but precision was significantly better for the Intermap NEXTMAP and, particularly, the Environment Agency LiDAR dataset. Only the LiDAR data revealed with any clarity small-scale and low relief features, for example scroll-bar palaeochannels on river terraces. The identification of sediment–landform assemblage zones from geomorphological survey permits the identification of the primary sedimentary process responsible for each assemblage and the attachment of an ideal sedimentary facies model to it. Each model can then be used to predict sedimentary composition, the optimal location of boreholes and the location of resource blocks. Combining the use of DEM data and the Spatial Analyst toolset within ArcGIS™ (ESRI) allows rapid accurate delineation of landforms and the use of cut and fill functions allows more accurate estimation of the volume of resources than the traditional calculations based on area and average thickness. These new methods improve the accuracy and cost-effectiveness of geomorphology-based aggregate assessments, notably where the mineral-bodies are concealed beneath minimal overburden and produce characteristic landforms. [Copyright &y& Elsevier]

Abstract: It is generally accepted that a gravel-bed river will aggrade if the supply of sediment to the river is increased. In a series of flume experiments using constant discharge and gravel feed rate, sand feed rates were increased to 6.1 times that of gravel. The slope of the bed decreased with increasing sand supply, indicating that the increased sediment load could be transported at the same rate due to a decrease in shear stresses. These results extend previous experiments to a wider range of boundary conditions. A recent surface transport model is used to predict the changes in bed composition and transport using the same sediment supply composition and feed rates as in the laboratory experiments. This model reasonably predicts a decrease in the reference shear stresses of the sand and gravel fractions as the sand supply is increased. An increase in sand supply can increase the mobility of gravel fractions in the stream bed, which can lead to bed degradation and preferential evacuation of these sediments from the river. [Copyright &y& Elsevier]

The combined use of allocation modeling and geographical information system (GIS) technologies for providing quantitative assessments of aggregate supply and demand is evaluated using representative data for the Front Range Urban Corridor (FRUC) in Colorado. The FRUC extends from the Colorado-Wyoming border to south of Colorado Springs, and includes Denver and the major urban growth regions of Colorado. In this area, aggregate demand is high and is increasing in response to population growth. Neighborhood opposition to the establishment of new pits and quarries and the depletion of many deposits are limiting aggregate supplies. Many sources are already covered by urban development or eliminated from production by zoning. Transport of aggregate by rail from distant resources may be required in the future.Two allocation-modeling procedures are tested in this study. Network analysis procedures provided within the ARC/INFO software, are unsatisfactory. Further aggregate allocation modeling used a model specifically designed for this task; a modified version of an existing Colorado School of Mines allocation model allows for more realistic market analyses. This study evaluated four scenarios. The entire region was evaluated with a scenario reflecting the current market and by a second scenario in which some existing suppliers were closed down and new potential suppliers were activated. The conditions within the Denver metropolitan area were studied before and after the introduction of three possible rail-to-truck aggregate distribution centers.GIS techniques are helpful in developing the required database to describe the Front Range Urban Corridor aggregate market conditions. GIS methods allow the digital representation of the regional road network, and the development of a distance matrix relating all suppliers and purchasers. [Copyright &y& Elsevier]

A detailed study of the seabed surrounding dredge pits created during the mining of marine aggregate from a small licence off the south coast of the United Kingdom (‘Licence Area 122⁄3’) has been completed. Over 350 km of high-resolution sidescan sonar imagery and 177 sediment samples have been obtained over a study area extending 10 km either side of the dredge zone (representing one full tidal excursion) in order to identify far-field effects on both physical and biological resources of the seabed. The physical results presented here for Area 122⁄3 clearly show that the physical impact of dredging (without screening) on the seabed is limited to a zone within approximately 300 m downtide of the dredge area. This will generally be within the dredge licence boundary due to operational procedures. There is no evidence of suspended sediments falling to the seabed beyond this zone and causing significant changes, which may be manifested as infilling of small pits by fine sediments, siltation within crevices or development of migratory sand ripples. However, there is some statistical evidence from grab sampling that surface sediments have a greater sand fraction within the excursion track of the plume, than those sediments either side. Despite this small change in seabed particle size distribution, the benthic communities do not exhibit a detectable impact, as reported in the accompanying paper by NEWELL et al. (2002). Analysis of ADCP backscatter data supports recent evidence for development of a near bed benthic boundary plume some 2–4 metres thick and a few tens of metres wide which extends beyond the limits of the dredge activity. On an extraction licence undertaking cargo screening, this near bed plume may exceed 4.5 kilometres downtide. Such a phenomenon provides a potential mechanism for impacting physical and benthic resources well beyond the dredge licence boundary and requires further investigation. [ABSTRACT FROM AUTHOR]

A mixed-size sediment transport model using only two fractions, sand and gravel, offers practical advantages in terms of the required input and conceptual advantages by readily incorporating the nonlinear effects of sand content on transport rate. A two-fraction model is developed from flume and field transport observations. Sand and gravel transport rates are collapsed to a single transport function using a scaling parameter representing incipient motion for each fraction. The incipient motion function is consistent with established values in the limit of pure sand and gravel beds and shows a sharp change with increasing sand content over the transition from a clast- to matrix-supported bed. A two-fraction model captures an important and previously unmodeled nonlinear effect of sand content on gravel transport rate and suggests important implications for a number of fluvial processes, including the response of channels to sediment supply and the mechanism for abrupt sorting in gravel/sand transitions. [ABSTRACT FROM AUTHOR]

• Tests and in situ behaviour of relatively unusual geomaterial. • Study of structures previously not well documented. • Large sized laboratory testing. • Two fully instrumented full-scale culverts. • Sophisticated modelling and calibration of model parameters. Intermediate stiffness culverts behave in a manner between that of rigid structures, where the structural stiffness dominates, and flexible culverts where the soil properties are most important. Analysis and design of intermediate stiffness culverts requires a thorough understanding of soil-structure interaction. In addition the use of recycled concrete aggregate (RCA) as a backfill material to culverts is not well studied. Here the behaviour of two fully instrumented full scale intermediate stiffness culverts, one of which was backfilled with RCA, was examined by means of a series of large scale laboratory tests, detailed in situ testing and by a series of numerical models. It was found that the RCA behaves as a competent engineering material in a manner very similar to the natural sand and gravel tested. Both materials dilate strongly on loading and exhibit strong non-linearity of stiffness. The Hardening Soil Model (HSM) constitutive relationships were found to be well suited to these materials. A combination of in situ geophysics and some measurements and modelling of locally instrumented large scale laboratory testing was required to give the necessary input parameters. Monitoring of the 6 m high arch culvert showed the structure distorted in a linear elastic manner with distortions less than 20 mm, strains induced in the structural concrete less than 700 microstrain and earth pressures close to theoretical in situ (K 0) earth pressures. No measureable movement was observed in the 300 mm thick, 3 m high box culvert. The numerical models successfully captured the behaviour of both culverts. The work demonstrates that potential savings could be made in the development of intermediate stiffness culverts, particularly in the required thickness of the soil cover and the size of the backfill zone but possibly also in the size of the structural elements. [ABSTRACT FROM AUTHOR]

Sand and gravel quarry planning must guarantee the public interest in the procurement of raw materials while ensuring environmental sustainability. An Analyzing Planning Support System for sand and gravel quarry plan can assist decision-makers during the planning process. The proposed Analyzing PSS uses integrating geologic, economic, environmental, and geographic information to quantify raw materials and the size of quarries. This kind of tool is useful to support public authority decisions. The study provides the results of an experience conducted in the province of Brescia (NUT 3 in Northern Italy). [ABSTRACT FROM AUTHOR]