The Study of Effects of Aggregates on C.B.R. Value

2021 ◽  
Vol 9 (9) ◽  
pp. 1265-1271
Author(s):  
Atul Lad
Keyword(s):  
Soil Properties ◽  
Base Material ◽  
Engineering Practice ◽  
Coarse Aggregates ◽  
Earth Construction ◽  
The Earth ◽  
Compression Parameter ◽  
Earth Structures ◽  
Reinforcing Material ◽  
Proper Analysis

Abstract: In engineering practice, the earth construction requires the compaction of the existing subgrade by improving the density and strength of the data. All types of earth structures, i.e., highways, pavements, etc., rest directly on the soil beneath them. The safety of these entities depends upon the strength/bearing capacity of the soil over which these are constructed. Therefore, a proper analysis of the soil properties and the design of their compression parameter become necessary to ensure that these structures remain stable and are safe against unequal settlements. To determine the suitability of any soil type for use as subgrade, subbase, or base material, one of the parameters generally used is the California bearing ratio (C.B.R.). The coarse aggregates available as a reinforcing material can enhance soil properties and increase its C.B.R. value. This paper will study the effects of coarse aggregates on the C.B.R. value, determine suitable size range of aggregates with their percentage, and their application for the earth structures. Keywords: Soil, CBR, Aggregate, Compaction, pavement.

scholarly journals Design Optimisation Strategies for Solid Rammed Earth Walls in Mediterranean Climates

Energies ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 325
Author(s):  
Giada Giuffrida ◽  
Maurizio Detommaso ◽  
Francesco Nocera ◽  
Rosa Caponetto
Keyword(s):  
Energy Demand ◽  
Construction Material ◽  
Base Material ◽  
Energy Performance ◽  
Embodied Energy ◽  
Rammed Earth ◽  
Earth Construction ◽  
Material Choice ◽  
Earth Walls ◽  
Raw Earth

The renewed attention paid to raw earth construction in recent decades is linked to its undoubted sustainability, cost-effectiveness, and low embodied energy. In Italy, the use of raw earth as a construction material is limited by the lack of a technical reference standard and is penalised by the current energy legislation for its massive behaviour. Research experiences, especially transoceanic, on highly performative contemporary buildings made with natural materials show that raw earth can be used, together with different types of reinforcements, to create safe, earthquake-resistant, and thermally efficient buildings. On the basis of experimental data of an innovative fibre-reinforced rammed earth material, energy analyses are developed on a rammed earth building designed for a Mediterranean climate. The paper focuses on the influences that different design solutions, inspired by traditional bioclimatic strategies, and various optimised wall constructions have in the improvement of the energy performance of the abovementioned building. These considerations are furthermore compared with different design criteria aiming at minimising embodied carbon in base material choice, costs, and discomfort hours. Results have shown the effectiveness of using the combination of massive rammed earth walls, night cross ventilation, and overhangs for the reduction of energy demand for space cooling and the improvement of wellbeing. Finally, the parametric analysis of thermal insulation has highlighted the economic, environmental, and thermophysical optimal solutions for the rammed earth envelope.

Free oscillation observations through 1968

1969 ◽  
Vol 59 (5) ◽  
pp. 2079-2099
Author(s):  
John S. Derr
Keyword(s):  
Confidence Level ◽  
Free Oscillation ◽  
Statistical Tests ◽  
Standard Errors ◽  
Free Oscillations ◽  
The Earth ◽  
Earth Models ◽  
Earth Structures ◽  
Path Dependent ◽  
Consistent Basis

abstract All observations of the free oscillations of the Earth published through 1968 are weighted to produce a set of means and standard errors of the means. Fundamental orders 0 to 97 for spheroidal and 2 to 99 for torsional are treated, as well as many overtones up to order 49. Statistical tests indicate that some observations are path dependent at the 99 per cent confidence level. Comparison of these means and standard errors with published Earth models indicate that they form a consistent basis for inversion of free oscillation observations to infer Earth structures.

On-Site Inspection and Analysis on Earth Architecture’s Enclosure Construction

2013 ◽  
Vol 357-360 ◽  
pp. 492-498
Author(s):  
Hong Yu ◽  
Hai Jun Sun
Keyword(s):  
Energy Consumption ◽  
Energy Saving ◽  
Environmental Protection ◽  
Influential Factors ◽  
Earth Construction ◽  
The Earth ◽  
New Countryside ◽  
Actual Energy Consumption ◽  
Saving Effect ◽  
Good Heat

In order to assess the human settlements situation of earth construction and analyse Environmental protection and energy saving effect of the earth construction's enclosure-construction, we choose Jinan's earth construction--adobe houses--to conduct the detection and analysis of energy saving and were based on the factual date to calculate enclosure-construction's heat transfer coefficient K and the actual energy consumption to analyses the influential factors of the energy consumption and determine the main part of the energy saving effect of energy consumption based on the Extensive research of the ecological environment and earth construction in Shandong province. The results show that the typical enclosure-structure with good heat saving capacity can maintain the indoor thermal stability. Through the calculation of heat retaining structure, we can know that the tested adobe house's energy consumption is larger than normal house. it suggested that the earth construction has the characteristics of better energy saving and environmental protection. seeing that the factual tested adobe house's lower intensity , bad decoration and imperfection ,we put forward the suitable earth buildings scheme of the construction of new countryside.

Science and creativity

2020 ◽  
Author(s):  
Flavia Bruno
Keyword(s):  
Chemical Reactions ◽  
Scientific Conference ◽  
Scientific Terminology ◽  
Educational Standard ◽  
The Earth ◽  
Hands On ◽  
Earth Structures ◽  
Lithospheric Plates ◽  
Living Organisms

<p>I teach Natural Sciences in a Liceo Artistico, a type of secondary school in Italy. It is designed to give students the skills to progress to any university, but specifically devoted to art related topics.<br>During my career I have been following the national educational standard of the Ministero dell’Istruzione, dell’Università e della Ricerca of my Country.<br>During the years students are involved in meaningful hands-on activities   such as the study of the rocks in the country, preparation of easy chemical reactions and observations through a microscope of vegetal and animal organisms. These last ones are very interesting in a Liceo Artistico where many topics focus on the study of the morphology.<br>The theory confirms what the students learn during the practical activities, furthermore it is important to acquire a correct scientific terminology as well as to be able to express scientific issues.<br>I teach during the year the following main topics:<br>Science of Earth: the Solar System, the two motions of the Earth, structures of the Earth surface (rivers, lakes, glaciers, oceans and seas), the Earth’s Spheres, the movement of lithospheric plates.<br>Biology: the characteristics and functions of living organisms especially the cells and the biodiversity. The Evolution, Mendel’s genetic laws, organism-environment relationship in order to valorize and to maintain the biodiversity. Chemistry: state of matter, classification of matter, the Mendeleev’s Periodic Table, the main chemical reactions, atomics models, chemical bonds, chemical nomenclature.<br>The extra-curricular course proposal of my school (POFT-Piano dell’Offerta Formativa Triennale) includes my project whose title is “Science and creativity”. The achievement is to create a link between scientific subjects and the art ones in order to approach knowledge which appear distant but have really many points to share.<br>Every year some classrooms study different topics such as the Nanoparticles, Biomimetic and this year the Adaptations of the animals.<br>After a scientific conference, plastic models and graphic drawings will be realised by the students, who starting from the scientific reality, can express their creativity.<br>During the years I organize some educational visits for example to the Botanic Garden as well as to the countryside; in this way the students have opportunities to create an e-book with texts and photographs.<br>For instance two years ago my classroom created an e-book with botanical cards and the following year another one with the title “Rocce a Milano” where students took pictures and texts about this topic.<br>Many classrooms and teachers are involved in this project for example Plastic and Drawing teachers, as well as Multimedia teachers. I manage to gather the interested teachers and to realize the projects.<br>With our productions we participate in competitions and we are sometimes selected.</p>

Le barrage OA-10B, un exemple de construction d'un barrage sur des dépôts d'origine glaciaire

1985 ◽  
Vol 12 (4) ◽  
pp. 838-848
Author(s):  
Michel Massiéra ◽  
Claude Pelchat
Keyword(s):  
Power Plant ◽  
Key Words ◽  
Glacial Till ◽  
Central Core ◽  
James Bay ◽  
The Earth ◽  
Earth Structures ◽  
Three Rivers

The OA-10B dam is one of the earth structures of the EOL (Eastmain – Opinaca – La Grande) project within the "La Grande" hydroelectric complex at James Bay, in the northwest of Quebec. Three rivers, the Eastmain, Petit Opinaca, and Opinaca, were diverted to the La Grande River to increase the hydropotential of the LG-2 power plant. Dam OA-10B, 25 m high, has a zoned section with an impervious moraine central core, and rests mainly on overburden foundations consisting of heterogeneous deposits of glacial till. The paper describes the different construction phases of the dam with emphasis on foundation treatments. Key words: construction, core trench, dam, dewatering, excavation, foundation, glacial till, instrumentation, moraine, treatment.

scholarly journals Cadmium in Cacao: ‘From Soil to Bar’ the Journey of Cadmium at a Farm Level

2021 ◽  
Author(s):  
Daniel Bravo ◽  
Margareth Santander ◽  
Jader Rodríguez ◽  
Sebastian Escobar
Keyword(s):  
South America ◽  
Soil Properties ◽  
Anthropogenic Activities ◽  
Farm Level ◽  
Post Harvest ◽  
The Earth

Abstract Cadmium (Cd) is a non-nutritive element present across the earth. In cacao crops from South America, Cd has become one of the biggest challenges due to its flux from soils, and due to the enriched content of this metal, it makes its way into the beans and finally affects the chocolate quality. This manuscript aims to show how the flux of Cd occurs, from the soil to the post-harvest phase and chocolate production, by analysing the possible inputs to the system in a single farm assessed as a model for enriched-Cd status. This study shows that both geogenic and anthropogenic activities have an incidence on the final Cd content in chocolate, especially with respect to soil properties, fertiliser applications, post-harvest treatments and chocolate production.

scholarly journals New Definition of Ultrafine Particles in Mine Paste and Its Relationship with Rheological Properties

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Jincheng Xie ◽  
Dengpan Qiao ◽  
Runsheng Han ◽  
Tao Deng ◽  
Jun Wang
Keyword(s):  
Rheological Properties ◽  
Ultrafine Particles ◽  
Size Range ◽  
Engineering Practice ◽  
Mathematical Significance ◽  
Analysis Model ◽  
Mine Backfill ◽  
Coarse Aggregates ◽  
Geometric Size ◽  
Definition Of

Mine backfill paste is generally composed of tailings and coarse aggregates. In engineering practice, the definitions in fill material classification are vague. In this paper, the size range of ultrafine particles is defined by the Stokes sedimentation test and hydraulic coarseness method. The size range of ultrafine particles is affected not only by the geometric size of the particles but also by the physical characteristics of the particles themselves. This definition has more comprehensive considerations and stricter physical and mathematical significance than the traditional definition of ultrafine particles based only on size. There is a strong correlation between ultrafine particles in fill materials and the rheological properties of the mine backfill paste. In this study, through experiments and correlation analysis, it was found that the content of ultrafine particles is positively correlated with the plastic viscosity of the mine backfill paste, and its growth range is exponential. The coarse aggregate content is positively correlated with the yield stress of the mine backfill paste. A regression analysis model was established for the rheological properties of mine backfill paste. The model has few factors and high correlation, so it can simply and efficiently predict the rheological properties of mine backfill paste and guide engineering practice.

scholarly journals Estimation of the earth dam strength with inelastic soil properties

2020 ◽  
Vol 883 ◽  
pp. 012021
Author(s):  
M Mirsaidov ◽  
T Sultanov ◽  
J Yarashov ◽  
Z Urazmukhammedova
Keyword(s):  
Soil Properties ◽  
Earth Dam ◽  
The Earth

3D glacial-isostatic adjustment models using geodynamically constrained Earth structures

2021 ◽  
Author(s):  
Meike Bagge ◽  
Volker Klemann ◽  
Bernhard Steinberger ◽  
Milena Latinović ◽  
Maik Thomas
Keyword(s):  
Solid Earth ◽  
Sea Level ◽  
Ice Sheet ◽  
Sea Level Change ◽  
Glacial Isostatic Adjustment ◽  
Level Change ◽  
Isostatic Adjustment ◽  
Mantle Viscosity ◽  
The Earth ◽  
Earth Structures

<p>The interaction between ice sheets and the solid Earth plays an important role for ice-sheet stability and sea-level change and hence for global climate models. Glacial-isostatic adjustment (GIA) models enable simulation of the solid Earth response due to variations in ice-sheet and ocean loading and prediction of the relative sea-level change. Because the viscoelastic response of the solid Earth depends on both ice-sheet distribution and the Earth’s rheology, independent constraints for the Earth structure in GIA models are beneficial. Seismic tomography models facilitate insights into the Earth’s interior, revealing lateral variability of the mantle viscosity that allows studying its relevance in GIA modeling. Especially, in regions of low mantle viscosity, the predicted surface deformations generated with such 3D GIA models differ considerably from those generated by traditional GIA models with radially symmetric structures. But also, the conversion from seismic velocity variations to viscosity is affected by a set of uncertainties. Here, we apply geodynamically constrained 3D Earth structures. We analyze the impact of conversion parameters (reduction factor in Arrhenius law and radial viscosity profile) on relative sea-level predictions. Furthermore, we focus on exemplary low-viscosity regions like the Cascadian subduction zone and southern Patagonia, which coincide with significant ice-mass changes.</p>

scholarly journals Geosynthetic Reinforced Steep Slopes: Current Technology in the United States

2019 ◽  
Vol 9 (10) ◽  
pp. 2008 ◽  
Author(s):  
Yoo-Jae Kim ◽  
Ashley Russell Kotwal ◽  
Bum-Yean Cho ◽  
James Wilde ◽  
Byung Hee You
Keyword(s):  
Best Practices ◽  
Polymeric Materials ◽  
Cost Effective ◽  
The United States ◽  
Geosynthetic Reinforcement ◽  
Construction Specifications ◽  
The Earth ◽  
Earth Structures ◽  
Mechanically Stabilized ◽  
Steep Slopes

Geosynthetics is a crucial mechanism in which the earth structures can be mechanically stabilized through strength enforcing tensile reinforcement. Moreover, geosynthetic reinforcement stabilizes steep slopes through incorporating the polymeric materials, becoming one of the most cost-effective methods in not only accommodating budgetary restrictions but also alleviating space constraints. In order to explicate on the applicability and widen the understanding of geosynthetic reinforcement technology, a synthesis study was conducted on geosynthetic reinforced steep slope. This study is very important because in not only highlighting the advantages and limitations of using geosynthetic reinforcement but also in investigating the current construction and design methods with a view to determining which best practices can be employed. Furthermore, this study also identified and assessed the optimal condition of the soil, performance measures, construction specifications, design criteria, and geometry of the slope. To further concretize the understanding of these parameters or factors, two case studies were reviewed and a summary of the best practices, existing methods, and recommendations were drawn in order to inform the employment of geosynthetics in reinforcing steep slopes.

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