Summary: The castor plant (Ricinus communis L.) is a plant that has dif ferent benefits, such as the production of biodiesel and soil bioremediation. Due to the above, the castor plant’s ability to extract arsenic (As) was evaluated. For this, a randomized block experimental design with four repetitions was carried out. The evaluated treatments consisted of two types of biosolids (oxidation lagoon biosolids (BLO) and activated sludge biosolids (BLA) and four doses of As (0, 25, 50, 100 mg kg-1), under greenhouse conditions. As concentration was determined by inductively coupled plasma mass spectrometry (ICP-MS). From the quantification of As, the translocation factor (TF) and the bioaccumulation factor (FB) were estimated. The total nitrogen (N) content was quantified by the combustion method. Phosphorus (P) was analyzed by colorimetry using the metavanadate method, and the content of potassium (K), calcium (Ca), magnesium (Mg), copper (Cu), manganese (Mn), iron (Fe) and zinc (Zn) was quantified by atomic absorption. For percentage of oil The Soxhlet method was used in the seed. The plant height and the dry weight of biomass did not vary due to the treatment ef fect (P ≤ 0.05). The Translocation Factor (TF) and the Bioconcentration Factor (BCF) registered ranges of 0.20 - 0.63 and 0.28 - 0.75, respectively. The applied doses of As did not af fect the biomass and nutrient absorption in the castor plant, which indicates that this plant species is tolerant to toxicity with productive potential in soils contaminated with this element, in concentrations up to 100 mg kg-1.

Resumen: La higuerilla (Ricinus communis L.) es una planta que tiene diferentes beneficios, como la producción de biodiesel y la biorremediación de suelo. Debido a lo anterior, se evaluó la capacidad de la higuerilla para extraer arsénico (As). Para ello, se realizó un diseño experimental de bloques al azar con cuatro repeticiones. Los tratamientos evaluados consistieron en dos tipos de biosólidos (biosólidos de lagunas de oxidación (BLO) y biosólidos de lodos activados (BLA) y cuatro dosis de As (0, 25, 50, 100 mg kg-1), bajo condiciones de invernadero. La concentración de As se determinó por espectrometría de masas por plasma acoplado inductivamente (ICP-MS). A partir de la cuantificación de As se estimó el factor de translocación (FT) y el factor de bioacumulación (FB). El contenido de nitrógeno (N) total se cuantifico por el método de combustión. El fósforo (P) se analizó por colorimetría por el método de metavanadato, y el contenido de potasio (K), calcio (Ca), magnesio (Mg), cobre (Cu), manganeso (Mn), hierro (Fe) y zinc (Zn) que se cuantificaron por absorción atómica. Para porcentaje de aceite en la semilla se utilizó el método Soxhlet. La altura de planta y el peso seco de biomasa no variaron por efecto de tratamiento (P ≤ 0.05). El Factor de translocación (FT) y el Factor de bioconcentración (FBC) registraron rangos de 0.20 - 0.63 y 0.28 - 0.75, respectivamente. Las dosis aplicadas de As no afectaron la biomasa y absorción de nutrientes en la planta de higuerilla, lo cual indica que esta especie vegetal es tolerante a la toxicidad con potencial productivo en suelos contaminados con este elemento, en concentraciones hasta de 100 mg kg-1.

Resumen La cuenca baja del río Acre se ubica en una zona de deforestación con la implementación de pastizales para ganado vacuno en suelos susceptibles a la erosión y clima ecuatorial. La existencia de mataderos y ganado vacuno en el municipio de Boca do Acre, en el estado de Amazonas, es uno de los problemas vinculados a la deforestación en la Amazonía brasileña. Ante este escenario, se presentó una estimación de las pérdidas de suelo con la aplicación de la Ecuación Universal en un sistema de información geográfica. En la metodología, se desarrolló una base de datos con información vectorizada para extraer las áreas de tipos de suelo y cobertura del suelo, incluyendo el análisis espacial de pendientes extraído del modelo digital de elevación. Como resultado del análisis de las áreas por geoprocesamiento y vectorización, se obtuvieron los cálculos de las parcelas de erosión a través de tablas con los parámetros adoptados por los referentes científicos. Se encontró que el 60% de la pérdida de suelo ocurre en el área agrícola en el 11% del territorio de la cuenca, siendo predominantemente en áreas de asentamientos rurales en el estado de Acre. Como resultado de la estimación, la pérdida de suelo en la cuenca baja del río Acre fue de 386.422 t/ha/año, con una producción de 46 millones de toneladas de sedimentos por año.

Abstract The Lower Acre River Basin is located in an area of deforestation with the implementation of pastures for beef cattle ranching in soils susceptible to erosion and equatorial climate. The existence of slaughterhouses and beef cattle in the municipality of Boca do Acre, in the state of Amazonas, is one of the problems linked to deforestation in the Brazilian Amazon. Given this scenario, an estimate of soil losses was presented with the application of the Universal Equation in a geographic information system. In the methodology, a database was elaborated with vectorized information for the extraction of the areas of the types of soils and land cover, including the spatial analysis of slopes extracted from the digital elevation model. Due to the analysis of the areas by geoprocessing occurring by vectorization, the calculations of the erosion plots were obtained through tables with the parameters adopted by the scientific references. It was found that 60% of the soil loss occurs in the area of agriculture in 11% of the territory of the watershed, being predominantly in areas of rural settlements of the state of Acre. As a result of the estimate, soil loss in the Lower Acre River Basin was 386,422 t/ha/year, with a production of 46 million tons of sediment per year.

Resumo A Bacia do Baixo Rio Acre está localizada em uma área de desflorestamento com implantação de pastagens para pecuária de corte em solos suscetíveis à erosão e clima equatorial. A existência de abatedouros e pecuária de corte implantada no município de Boca do Acre, no Amazonas, é um dos problemas vinculados ao desmatamento da Amazônia Brasileira. Diante desse cenário, foi apresentada uma estimativa de perdas de solo com aplicação da Equação Universal em sistema de informação geográfica. Na metodologia, foi elaborado um banco de dados com informações vetorizadas para extração das áreas dos tipos de solos e cobertura da terra, incluindo a análise espacial de declividades extraídas do modelo digital de elevação. Em decorrência da análise das áreas pelo geoprocessamento ocorrer pela vetorização, foram obtidos os cálculos das parcelas de erosão através de tabelas com os parâmetros adotados pelas referências científicas. Foi constatado que 60% da perda de solo ocorrem na área de agricultura em 11% do território da bacia hidrográfica, sendo predominantemente em áreas de assentamentos rurais do estado do Acre. Como resultado da estimativa, a perda de solos na Bacia do Baixo Rio Acre foi de 386.422 t/ha/ano, com uma produção de 46 milhões de toneladas de sedimentos por ano.

Resumen: Las Reservas Ecológicas, son la base primordial para la subsistencia de la biodiversidad, desempeñan funciones cruciales para el mantenimiento de los ecosistemas, especialmente, en la preservación de los servicios ecosistémicos de regulación del clima y suministro de agua. Determinar la capacidad de acumulación del COS en tres ecosistemas de la Reserva Ecológica Arenillas (REAR) y la influencia que tienen con los factores de profundidad y el tipo de suelo, fue el objetivo de la investigación. Se partió de la hipótesis que dichos factores ejercen un efecto sobre las propiedades físicas-químicas del suelo, provocando la variabilidad del carbono. Se establecieron 14 unidades de muestreo para los tres ecosistemas; 1) Intervenido, 2) Bosque deciduo y 3) Bosque arbustal deciduo, se extrajo de cada unidad dos muestras de suelo a profundidades de (0-10 y 10-30 cm), dando un total de 28 muestras. Los resultados revelaron diferencias significativas entre los tres tipos de ecosistemas, permitiendo afirmar que, en la REAR, el contenido de COS es mayor en el ecosistema de Bosque deciduo, que en los denominados Bosque arbustal deciduo y la zona Intervenida. Así mismo, los suelos del tipo Alfisol y Entisol en el Bosque deciduo presentaron la mayor capacidad de almacenamiento de COS, siendo la capa superficial la de mayor acumulación en los tres ecosistemas. Se concluyó que las bajas precipitaciones, el aumento de la temperatura y la esporádica vegetación producida por actividades antrópicas, afectan el almacenamiento de COS, limitando la prestación de servicios ecosistémicos relacionados con la captura de carbono edáfico.

Abstract: Ecological Reserves are the primary basis for the subsistence of biodiversity, they play crucial roles in the maintenance of ecosystems, especially in the preservation of ecosystem services of climate regulation and water supply. The objective of the research was to determine the accumulation capacity of COS in three ecosystems of the Arenillas Ecological Reserve (REAR) and the influence of depth factors and soil type. It was hypothesized that these factors exert an effect on the physical-chemical properties of the soil, causing carbon variability. Fourteen sampling units were established for the three ecosystems; 1) Intervened, 2) Deciduous Forest and 3) Deciduous shrub forest, two soil samples were extracted from each unit at depths of (0-10 and 10-30 cm), giving a total of 28 samples. The results revealed significant differences between the three types of ecosystems, allowing us to affirm that, in the REAR, the COS content is higher in the deciduous forest ecosystem than in the deciduous shrub forest and the Intermediate zone. Likewise, Alfisol and Entisol soils in the deciduous forest had the highest COS storage capacity, being the surface layer the one with the highest accumulation in the three ecosystems. It was concluded that low precipitation, increased temperature and sporadic vegetation produced by anthropic activities affect COS storage, limiting the provision of ecosystem services related to soil carbon sequestration.

ABSTRACT: Arbuscular mycorrhizal fungi associate with legumes to enhance nitrogen fixation and nutrient absorption, thus promoting plant growth and reducing fertilizer usage. This study aimed to measure the degree of specificity and dependency of cover legumes inoculated with arbuscular mycorrhizal fungi from degraded soils with acidic pH and low fertility in the Alto Cumbaza sector, San Martín, Peru. Four species (Cajanus cajan, Canavalia ensiformis, Crotalaria juncea, and Vigna unguiculata) were evaluated with three types of fungi (Acaulospora rugosa, Acaulospora sp., and Ambispora appendicula) in a completely randomized design with three replications. Canavalia ensiformis inoculated with Acaulospora rugosa reached greater height (271.67 cm), while Crotalaria juncea with Acaulospora sp. showed higher aboveground biomass (27.52 g). Vigna unguiculata with Acaulospora rugosa exhibited high colonization (71.48%) and mycorrhizal dependency (54.40%), and Cajanus cajan with Ambispora appendicula showed high phosphorus content (5.01%). These interactions varied significantly, demonstrating the specificity and dependency of the associations. These findings are important for establishing programs to recover degraded soils with cover legumes inoculated with arbuscular mycorrhizal fungi.

RESUMEN: Los hongos micorrízicos arbusculares se asocian a las leguminosas para mejorar la fijación de nitrógeno y la absorción de nutrientes, promoviendo así el crecimiento vegetal y reduciendo el uso de fertilizantes. Este estudio buscó medir el grado de especificidad y dependencia de leguminosas de cobertura inoculadas con hongos micorrízicos arbusculares provenientes de suelos degradados, con pH ácido y baja fertilidad del sector de Alto Cumbaza, San Martín, Perú. Se evaluaron cuatro especies (Cajanus cajan, Canavalia ensiformis, Crotalaria juncea y Vigna unguiculata) con tres tipos de hongos (Acaulospora rugosa, Acaulospora sp. y Ambispora appendicula) en un diseño completamente aleatorizado con tres repeticiones. Canavalia ensiformis inoculada con Acaulospora rugosa alcanzó mayor altura (271,67 cm), mientras que Crotalaria juncea con Acaulospora sp. mostró mayor biomasa aérea (27,52 g). Vigna unguiculata con Acaulospora rugosa presentó alta colonización (71,48%) y dependencia micorrízica (54,40%), y Cajanus cajan con Ambispora appendicula mostró alto contenido de fósforo (5,01%). Estas interacciones variaron significativamente, evidenciando la especificidad y dependencia de las asociaciones. Estos hallazgos son importantes para el establecimiento de programas de recuperación de suelos degradados con leguminosas de cobertura inoculadas con hongos micorrízicos arbusculares.

ABSTRACT Soil is a medium that stores and transfers air, water, nutrients and heat to microorganisms and plants. Its water storage capacity is studied by analysing water retention curves (WRCs), which establish the relationship between soil water content and the force with which water is retained. The objective of this work was to evaluate the capacity of functional geostatistics in predicting the spatial distribution of water retention curves in two types of soils. Experimental areas with two types of soil, Andisol and Oxisol, were selected, and a regular grid of 75 sites was established, from which water retention curves were obtained at two depths. The curves were subjected to geostatistical functional analysis (GF), and the applicability of this method was evaluated by obtaining the usable water table (LAA) and comparing the results with experimental data obtained using traditional methods. Based on cross-validation, it was verified that GF produced a better fit for the Andisol since the coefficient of determination between the LAA values for the measured data and predictions was high, with an R2 of 99%; however, the proposed methodology was also reliable for the Oxisol, since an R2 of 94% was obtained at the two depths studied. air plants WRCs, WRCs , (WRCs) retained soils Oxisol selected 7 established GF, (GF) (LAA methods crossvalidation, crossvalidation cross validation, validation cross-validation high R 99% 99 however 94 (WRCs (GF 9

RESUMO O solo é um sistema que armazena e transfere ar, água, nutrientes e calor para microrganismos e plantas. Sua capacidade de armazenamento de água é estudada analisando a curva de retenção de água (WRC), que estabelece a relação entre a umidade do solo e a força com que ela é retida. O objetivo deste trabalho foi avaliar a capacidade preditiva da geoestatística funcional na distribuição espacial das curvas de retenção de água em dois tipos de solos. Foram selecionadas duas áreas experimentais, um Andisol e um Oxisol, nas quais foi estabelecida uma grade regular com 75 pontos, das quais foram obtidas curvas de retenção de água em duas profundidades. As curvas foram submetidas à análise geoestatística funcional (GF), sua aplicabilidade foi avaliada obtendo a tabela de água utilizável (LAA) e sua posterior análise espacial por métodos tradicionais nos quais os resultados foram comparados com os dados experimentais. Com base na validação cruzada, verificou-se que o uso de GF tem um melhor ajuste para o Andossolo, uma vez que o coeficiente de determinação entre os valores de LAA obtidos com os dados observados e aqueles obtidos com as previsões foi alto, com R2 de 99%; no entanto, para o Latossolo, a metodologia proposta também é confiável, uma vez que foi obtido um R2 de 94% nas duas profundidades estudadas. ar plantas WRC, WRC , (WRC) retida solos experimentais Oxisol 7 pontos GF, (GF) (LAA cruzada verificouse verificou se Andossolo alto R 99% 99 entanto Latossolo confiável 94 estudadas (WRC (GF 9

Abstract. - Reinforced concrete buildings subjected to seismic events may present different damages even though they have similar characteristics when designed with the regulatory seismic load combination. This results in higher costs and inconsistent structural reliability over the life cycle of the buildings. This work focuses on comparing the life cycle costs of reinforced concrete buildings of various levels located on soil with period Ts=0.75s and Ts=2.0s in Mexico City. For this purpose, a set of seismic load combinations proposed for the design of the buildings were used. The capacity of the designs was evaluated by incremental dynamic analysis and the structural reliability was examined by structural demand hazard curves. In addition, simulations of seismic demands were performed to estimate the damage that could occur during the life cycle of the buildings. Finally, initial and total damage costs were obtained for all the buildings analyzed. The results showed that some proposed load combinations provided cost savings while improving the structural performance of the buildings over time. These findings could be valuable to the construction industry, as they offer a clearer picture of how to optimize the design and seismic resistance of buildings.

Resumen. - Los edificios de concreto reforzados sujetos a eventos sísmicos pueden presentar distintos daños aun cuando estos tengan características similares cuando son diseñados con la combinación de carga sísmica reglamentaria. Lo anterior se traduce en mayores costos y una confiabilidad estructural no consistente durante el ciclo de vida útil de los edificios. Este trabajo se centra en comparar de los costos durante el ciclo de vida útil de edificios de concreto reforzado de varios nieles ubicados en suelo con periodos Ts=0.75s y Ts=2.0s de la ciudad de México. Para ello, se utilizaron un conjunto de combinaciones de cargas sísmicas propuestas para el diseño de los edificios. La capacidad de los diseños fue evaluada mediante el análisis dinámico incremental y la confiabilidad estructural se examinó mediante las curvas de peligro de demanda estructural. Además, se realizaron simulaciones de demandas sísmicas para estimar los daños que podrían ocurrir durante el ciclo de vida útil de los edificios. Por último, se obtuvieron los costos iniciales y los costos totales por daños de todos los edificios analizados. Los resultados demostraron que algunas combinaciones de cargas propuestas permitieron un ahorro en los costos, al mismo tiempo que mejoraban el comportamiento estructural de los edificios a lo largo del tiempo. Estos hallazgos podrían ser valiosos para la industria de la construcción, ya que ofrecen una visión más clara sobre cómo optimizar el diseño y la resistencia sísmica de los edificios.

Abstract Seismic bearing capacity of strip footings is a challenging task for geotechnical engineers due to its stochastic framework instigated by the natural uncertainties incorporated into geotechnical properties and earthquake parameters. Consequently, the introduction of the random field theory into reliability analysis may provide power tools to succor designers check how reliable their designs. This paper aims to assess the seismic bearing capacity of shallow strip footings resting on soils with randomly varying parameters. Bearing capacity formulas for purely cohesive and cohesive-frictional soils are considered. The influence of the type of the autocorrelation functions (ACFs), the scale of fluctuations (SOFs) and the coefficient of variation (COV) of the random parameters are investigated. Statistical moments, probability density function (PDF) and failure probability (Pf) of the seismic bearing capacity are computed. It is shown that the Single Exponential (SNE) ACF is the most appropriate function to characterize the spatial variability of the soil properties since it provides conservative results. On other hand, the results indicate that the increase in the coefficients of variation (COV) of the cohesion or the friction angle increases the variability of the seismic bearing capacity while this variability remains unaffected when the COV of the seismic coefficient increases. The results also highlight that the effect of the vertical SOF on the PDF and the failure probability is much more significant than that of the horizontal SOF. In addition, the mean seismic bearing capacity fluctuates slightly as the horizontal or vertical SOF increases so that the increment of variation is between 0.4% and 2% for the both two soil types. Consequently designs cohesivefrictional frictional considered ACFs, ACFs , (ACFs) SOFs (SOFs (COV investigated moments (PDF Pf (Pf computed SNE (SNE hand addition 04 0 4 0.4 2 types (ACFs 0.

Abstract In this work, we studied the effects of different types of soils contaminated with diesel on the germination and early growth of four plant species (Xanthium strumarium, Avena sativa, Daucus carota, and Cerinthe major). We used four potting soils that we contaminated with different levels of diesel: 2.5%, 5%, and the control (0%). The results showed that the effect of the contamination depends on the species. Thus, compared with the three other species, X. strumarium showed the best results. This species showed good germination rates, with a lower rate of 50%. Its root length and weight were stimulated in the contaminated soils, and its shoot growth was less affected than that of the other species. The results depend also on the soil type. X. strumarium showed the best results in the different types of soils; thus, in soil three, at 5% diesel, all species showed a germination rate of 0%, but X. strumarium showed a rate of 50%. Our study demonstrated the variation in diesel effects across different plant species and soil types. The four species showed different levels of tolerance that varied with diesel concentrations, soil types, and parameters. We recommend performing phytoremediation tests in soils contaminated with petroleum products using preferably X. strumarium, but it would be interesting to test the other species. Additionally, it would be interesting to test the tolerance of this species using seeds extracted from the burs, to investigate the role of the X. strumarium burs in its tolerance to diesel contamination. work Xanthium sativa carota major. major . major) 25 2 5 2.5% 0%. 0 0% (0%) Thus X rates 50 50% type thus concentrations parameters Additionally 2.5 (0% 2. (0 (

ABSTRACT Physical properties of the Technosols formed by the tailings deposition may constitute a physical barrier that limits water movement and plant development due to the properties received from those sediments. This study aimed to evaluate the physical quality of the Technosols formed by the deposition of sediments displaced by the Fundão Dam failure, Mariana, Minas Gerais State, Brazil, based on the evaluation of physical properties and Load Bearing Capacity Models (LBCM). For that, three areas under different vegetation types were selected: eucalyptus (Euc), forest with human-assisted revegetation (RF), and forest with native vegetation (NF). Three sampling subareas were demarcated in each area: non-impacted areas (Ni), and Technosols formed in directly impacted areas (Di), and partially impacted areas (Pi). Undisturbed samples were collected in two layers and subjected to the uniaxial compression test after equilibration at five matric potentials. Soil compression curves and LBCM were determined. Soil bulk density (BD), total porosity (TP), organic matter (OM), granulometry, and particle density (PD) were also determined. Clay content was less significant, and the silt and very fine sand content was significantly higher in the Technosols, generating an increase in BD and reduction in TP. Technosols generally exhibited greater load-bearing capacity due to higher pre-consolidation pressure values attained by these soils due to the lower clay and OM contents. High resistance of these soils is one limitation for revegetation of the areas evaluated, being necessary management practices to improve physical properties of the Technosols. failure Mariana State Brazil LBCM. . (LBCM) selected Euc, Euc , (Euc) humanassisted human assisted RF, RF (RF) NF. NF (NF) area nonimpacted non Ni, Ni (Ni) Di, Di (Di) Pi. Pi (Pi) potentials determined BD, (BD) TP, TP (TP) OM, (OM) granulometry PD (PD significant loadbearing load bearing preconsolidation pre consolidation contents evaluated (LBCM (Euc (RF (NF (Ni (Di (Pi (BD (TP (OM

Abstract Αn online questionnaire was developed to find out (i) whether geotechnical engineering instructors have available a variety of satisfactory educational material and (ii) the types of educational material they desire. The title of the questionnaire was phrased as “What Geotechnical Engineering Educational Material can we dream of?”, in order to convey that the main purpose of the survey project reported herein is to learn about these desired educational materials. In doing so, the survey also aims to assemble information on related issues, such as: existing educational materials, where do instructors search for them and how satisfied they are with available material. The questionnaire has 12 close-ended (four yes/no and eight multiple choice) and four open-ended questions. Of the 94 completed questionnaires received, 63 were deemed to be conscientious attempts to answer its questions and were analyzed in detail. The most revealing findings from the close-ended questions include the following. The majority of the instructors (52%) are not adequately satisfied with the material they use. Likewise, whereas a significant percentage have searched for additional material, a little less than half of them (45%) are not satisfied with material found. Respondents need materials for their lectures, materials to engage students outside lecture time and, to a lesser extent, materials to assess students. In terms of topics of interest, case studies and laboratory-related educational materials are the most popular. The online supplement of the paper includes broad-stroke and fine-stroke descriptions of desirable educational materials that provide directions for developing them. i (i ii (ii desire What of, , of?” so issues 1 closeended close ended yesno yes no choice openended open 9 received 6 detail following 52% 52 (52% use Likewise 45% 45 (45% found lectures extent interest laboratoryrelated laboratory popular broadstroke broad stroke finestroke fine of? 5 (52 4 (45 (5 (4 (

Abstract Modern tunnel design in urban areas heavily relies on numerical modeling to assess excavation stability and predict ground movement. Recent advancements in soil modeling, hardware, and software have facilitated the development of sophisticated 3D models within tight schedules. Urban tunnels are often shallow and excavated in challenging ground conditions, with proximity to existing structures and infrastructure. Consequently, numerical modeling of such tunnels involves highly nonlinear analyses with complex boundary conditions. Despite the widespread use of numerical modeling in tunnel research and design, there is a lack of publications addressing modeling procedures to ensure accurate and reliable results for highly nonlinear shallow tunnel analyses. This paper investigates the requirements for accurate results for highly nonlinear shallow tunnel analyses. The Finite Element Method (FEM) is employed with different mesh refinements and element types. The study focuses on the hypothetical excavation stability scenario explored by Carranza-Torres et al. (2013). Tunnel stability is assessed using Caquot's analytical solution based on the lower bound theorem of plasticity, as well as FEM modeling with the strength reduction method. The FEM numerical solution, which approaches the exact solution for the problem, provided a factor of safety slightly larger (2.3%) than Caquot's lower-bound solution. The results of the FEM modeling indicate that a significantly less refined mesh is required to achieve accurate results for highly nonlinear shallow tunnel analyses when adopting 2nd-order elements (i.e., quadratic interpolation) instead of 1st-order elements (i.e., linear interpolation). This study improves our understanding of FEM modeling requirements and provides practical insights regarding the numerical modeling of highly nonlinear shallow tunnels in urban areas. movement hardware D schedules conditions infrastructure Consequently (FEM types CarranzaTorres Carranza Torres al 2013. 2013 . (2013) Caquots Caquot s plasticity method problem 2.3% 23 2 3 (2.3% lowerbound 2ndorder ndorder 2nd order nd i.e., ie i e (i.e. interpolation 1storder storder 1st st interpolation. 201 (2013 2.3 (2.3 i.e. (i.e 20 (201 2. (2. i.e (20 (2 (

Abstract This paper discusses some points of the evolution of Engineering Geology based on a survey of historical facts, books, and other types of publications and technical reports and analyzes the teaching in engineering schools, specifically in the São Carlos School of Engineering, at University of São Paulo (EESC/USP). The survey involved the main topics considered in the teaching of Engineering Geology and both successes and challenges of the teaching experience at undergraduate and graduate levels at EESC/USP over the past 50 years are presented. Engineering Geology teaching has undergone different phases and adaptations to the evolution of knowledge and research procedures. According to the survey, it focuses on four large groups of didactic activities for the current decade and, perhaps, for the next one in several countries. The first group refers to access to materials of each topic in the format of books, videos, and lectures available on websites and the second includes face-to-face activities on the solution of practical problems related to a specific topic. The third group focuses on field and laboratory works, whereas the fourth comprehends development and analyses of specific civil work projects, mineral exploration, and environmental problems according to both face-to-face and non-face-to-face methodologies. facts books schools EESC/USP. EESCUSP . EESC USP (EESC/USP) 5 presented procedures perhaps countries videos facetoface face works projects exploration nonfacetoface non methodologies (EESC/USP

Abstract Recycled construction and demolition waste (RCDW) has demonstrated geotechnical properties that encourage it to be used in reinforced soil structures (RSS) with geosynthetics. However, the interaction between RCDW and reinforcements needs to be better understood, given its importance for design. This paper presents a qualitative study on the interaction between geogrid and recycled sands by means of pull-out tests performed on small equipment. Tests with the same degree of compaction and a geogrid buried in different types of recycled and natural sands (for comparison purposes) were performed. The characterisation of the materials was carried out in the laboratory and the variability of their geotechnical properties was evaluated. In addition, fill material moisture content was investigated as another potential factor influencing soil-geogrid interface shear. The results of the pull-out tests demonstrated the specific influences of the factors investigated. The comparative study showed that recycled sands can be suitable materials to be used as backfill in geosynthetic reinforced soil structures, meeting physical, mechanical and environmental requirements for this kind of work. (RCDW RSS (RSS geosynthetics However understood design pullout pull equipment purposes evaluated addition soilgeogrid shear physical work

Abstract Thin spray-on liners (TSLs) are a promising rock support method due to their ease of application and versatility. However, their effectiveness relies on experience and lacks a complete scientific understanding. To bridge some of the knowledge gaps existing in support mechanisms, this study investigated the effect of different parameters on the shear-bond strength of TSLs as a surface support in underground excavations. The parameters included liner thickness, curing period, material type and surface cleanliness. A polymer based cementitious TSL was utilized while the material type included quartz and sandstone rocks and 30 MPa concrete. Liner thicknesses included 16.2 mm, 20.2 mm, 24.2 mm, 28.2 mm, and 32.2 mm while curing periods were 7 days, 14 days, and 28 days. It was observed that the TSL shear-bond strength varied with different materials. Quartz with the lowest porosity had the lowermost shear-bond strength at all liner thicknesses and curing periods. The shear-bond strength improved with liner thickness up to 24.2 mm and then decreased up to 32.2 mm due to the optimum thickness effect. It also increased with curing period. Oil reduced the shear-bond strength for all the material types at all liner thicknesses and curing periods. sprayon spray (TSLs versatility However understanding mechanisms shearbond shear bond excavations period cleanliness 3 concrete 162 16 2 16. 202 20 20. 242 24 24. 282 28. 322 32 32. days 1 materials

Resumen Objetivo: Evaluar el efecto de diferentes tipos de utilización de la tierra en las reservas de carbono orgánico en un suelo Ferrítico Rojo oscuro típico. Materiales y Métodos: La investigación se desarrolló en un punto de observación permanente, ubicado en la localidad de Guaro, municipio Mayarí, provincia Holguín. Se tomaron muestras de suelo a la profundidad de 0-20, 20-40 y 40-60 cm, en tres tipos de utilización de la tierra: bosque de Pinus cubensis Griseb., pasto natural (Paspalum notatum Alain ex Flügge) y Saccharum spp., a los que se les determinó el carbono orgánico total. Además, se tomaron muestras sin disturbar para determinar la densidad aparente. Resultados: Se encontraron diferencias significativas en las reservas de carbono orgánico del suelo entre los tres tipos de utilización de la tierra, a una profundidad de 0-20 cm. En el pasto natural fue donde hubo mayor reserva. Le siguió Saccharum spp y el bosque de P. cubensis. Hubo incremento en la tasa de acumulación de carbono edáfico con la profundidad en todos los tipos de utilización de la tierra. Se encontraron los mayores valores en la profundidad de 0-20 cm, que disminuyeron con el perfil. Solo hubo cifras negativas en el bosque de P. cubensis, a profundidad de 40-60 cm. Conclusiones: Las mayores reservas de carbono se hallaron en terrenos con P. notatum. Le siguieron Saccharum spp. y P. cubensis. Los tipos de uso de la tierra con menor actividad humana mostraron las tasas más altas de acumulación de carbono y mejor calidad del suelo.

Abstract Objective: To evaluate the effect of different types of land use on organic carbon stocks in a typical dark red ferritic soil. Materials and Methods: The research was developed in a permanent observation point, located in the Guaro locality, Mayarí municipality, Holguín province. Soil samples were taken at 0-20, 20-40 and 40-60 cm depth, in three types of land use: Pinus cubensis Griseb. forest, natural pasture (Paspalum notatum Alain ex Flügge) and Saccharum spp. to which total organic carbon was determined. In addition, undisturbed samples were taken to determine the bulk density. Results: Significant differences in soil organic carbon stocks were found among the three types of land use, at a depth of 0-20 cm. The natural pasture had the highest stock. It was followed by Saccharum spp and P. cubensis forest. There was increase in the rate of edaphic carbon accumulation with depth in all types of land use. The highest values were found in the 0-20 cm depth, which decreased with profile. There were negative figures only in the P. cubensis forest, at 40-60 cm depth. Conclusions: The highest carbon stocks were found in soils with P. notatum. This was followed by Saccharum spp. and P. cubensis. Land use types with less human activity showed the highest rates of carbon accumulation and better soil quality.