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Geophysical methods are potent tools for geotechnical site characterization in a non-destructive way. They improve the extrapolation of punctual data from direct survey methods, allowing a fast and cost-effective evaluation of large areas. Ground Penetrating Radar (GPR) and DC electrical resistivity (ER) are the most requested methods for geotechnical and geoenvironmental applications. Their use, however, is usually uncoupled, with no sharing of information from one method to another to improve data interpretation. This case study illustrates the development of protocols and scripts in R© programming language for ER and GPR data analysis with Standard Penetration Tests (SPT) data to produce more accurate information on subsurface conditions concerning lithology, water content, and groundwater table (GWT) position. The SPT data were used to associate resistivity ranges with different soil lithologies and GPR pulse velocities for estimating the soil water content. Estimated water content values aided in interpreting ER data and locating the groundwater table. The contacts between layers in the radargrams allowed the refinement of the ER model, rendering 3D volumes for each soil layer in situ.

The mechanical behavior of municipal solid waste (MSW) is a critical issue in environmental geotechnics, given the pollution and public health risks associated with slope failures. In Brazil, waste composition is expected to change due to the hierarchy of sustainable practices established by the National Solid Waste Policy, which aims to improve the recovery of organic and recyclable materials. Not much progress has been made since the implementation of this law; thus, its effects on the design and operation of landfills are not fully clear. This study presents and discusses compaction and shear strength parameters of dry MSW after mechanical sorting of medium and large recyclable items and shredding. The maximum dry unit weight for the standard Proctor compaction test ranged from 6.6 to 10.0 kN/m3 and the optimum moisture content ranged from 20% to 42%. Stress-displacement curves of direct shear tests showed strain hardening and shear strength parameters of Mohr-Coulomb envelopes were displacement-dependent. The friction angle ranged from 3.2° to 42.9° and the cohesion intercept ranged from 1.3 to 31.3 kPa, at a displacement of 9 mm (15% of the specimen length). These results are in line with the literature, since a high content of waste materials that proved to affect geotechnical properties, such as plastic, paper, cardboard, textile, and glass, remained after pre-treatment.

Maximum shear modulus (G0) has been used in various geotechnical jobs (e.g., seismic site assessment, machine vibration and pile driven). Laboratory and in situ determination of G0 is not a current practice in Brazil. G0 can be estimated from empirical correlations based on in situ tests like Standard Penetration Test (SPT) and Cone Penetration Test (CPT) in the preliminary design phase. Several empirical correlations to estimate G0 from SPT N value have been developed and are available in the literature. However, most of these correlations were established based on experience with well-behaved soils formed in temperate and glacial zones, which may not always be used for tropical soils. This paper assessed and discussed the applicability of some correlations for G0 estimative from SPT data in lateritic and saprolitic soils. The classical correlations for sedimentary soils underestimated G0 of tropical soils. After updating the database, the tropical soils correlations reasonably estimated G0 for the lateritic ones, which was not the case for the saprolitic soils. It was observed that differentiating the soils only as lateritic or saprolitic was not adequate for a good G0 estimate for the saprolitic sandy soils. It was found that only the lateritic soils correlation can be used with caution as a preliminary attempt to estimate G0 from SPT N value in soils with similar characteristics to the ones presented in this paper.

The seasonal variability of geotechnical parameters in the unsaturated zone is typically neglected in the design of geotechnical works. In most of the geotechnical projects the parameters are determined only for the saturated condition. Although it is known that this condition is the most critical to soil strength and deformability, this conservative approach may neglect a possible important contribution of the unsaturated condition, resulting in an increase in the cost of the geotechnical solution. This paper presents and discusses the site characterization of the active zone of an unsaturated sandy soil profile under different suction conditions. Laboratory tests with controlled suction (retention curves, triaxial compression with bender elements and oedometer tests) were carried out on undisturbed samples collected from 1.0 to 5.0 m depth. The results show that strength and deformability parameters are strongly affected by soil suction and are less influenced by confinement stress up to 5.0 m depth. All the investigated subsoil profile shows a collapsible behavior, more pronounced closer to the ground surface and under the effect of higher suction values. The findings highlight the importance of incorporating the suction influence in the site investigation, parameter determination, and geotechnical design for more economical, reliable, and environmentally sustainable solutions.

Made available in DSpace on 2022-05-01T10:19:01Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-07-10 This paper presents a methodology for selecting areas with potential sources of groundwater pollution and its application in an industrialized municipality in the interior of São Paulo. As there are multiple potential sources of pollution and difficulty in establishing criteria for prioritizing areas to be investigated, it is necessary to use tools and techniques that make it possible to guide and plan in situ site inspections. The data from CETESB's registry of pollution source activities was used applying the POSH-IG method associated with Kernel density spatial analysis in a Geographic Information System. The findings revealed a hot spot of 6.96 km² with 383 industries with high groundwater pollution potential; within it the highest range of Kernel density presents 124 industries occupying an area of 0.41 km. A major difference between the number of contaminated sites registered by CETESB (two) and the quantity (383) of sources with high pollution potential (POSH-IG index equal to 3) was observed at that hotspot area. Therefore, the applied methodology was satisfactory in indicating areas of interest for field inspections, identifying 6.96 km² area in a 450.38 km² municipality, which has a high polluting potential for groundwater and only two known contaminated areas. This approach can be used to guide the inspection of sites that could contaminate groundwater. Universidade Estadual Paulista (UNESP) Faculdade de Engenharia de Bauru Centro Universitário SENAC ECD Ambiental Universidade Estadual Paulista (UNESP) Faculdade de Engenharia de Bauru

Made available in DSpace on 2022-04-29T07:12:46Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-12-05 The Cone Loading Test (CLT) consists of the execution of a load test on the piezocone probe in conjunction with the CPT test. The CLT yields the modulus ECLT, a parameter that can be used in the estimative of foundation settlement. It is also presented here the interpretation and the process to determine ECLT values from the stress-displacement curves obtained from cone loading tests. Several CLT tests were conducted at the experimental research site of São Paulo State University, Bauru-SP-Brazil. The geotechnical profile at the studied site is a brown to bright red slightly clayey fine sand, a tropical soil common to this region which is lateritic, unsaturated and collapsible. The results of CLT tests satisfactorily represent the behavior of the investigated soil. The penetrometric modulus ECLT for each depth was calculated considering the elastic behavior in the initial linear segment of the soil stress-strain curve. The ECLT moduli obtained for the various tests were compared to moduli obtained from PMT and DMT test results performed at same studied site. The shear modulus degradation curves obtained from the CLT tests are also presented. The comparison to PMT and DMT results indicates the CLT test is a viable complementary test to the CPT in the quest for better understanding stress-strain behavior of soils. Further, the CLT test provides a graphic visualization of the degradation of the shear modulus with increasing levels of strain. As a hybrid geotechnical test, CPT+CLT can be valuable in the investigation of non-conventional collapsible soils, whose literature lack reference parameters for the prediction of settlement in the design of foundations. © 2013 ejge. Department of Geotechnical Engineering São Carlos School of Engineering University of São Paulo (USP), Avenida do Trabalhador Sancarlense 400, 13.566-590, São Carlos (SP) Department of Civil and Environmental Engineering UNESP - São Paulo State University, Av. Eng. Luiz Edmundo C. Coube 14-01, 17.033-360, Bauru (SP) Department of Civil and Environmental Engineering UNESP - São Paulo State University, Av. Eng. Luiz Edmundo C. Coube 14-01, 17.033-360, Bauru (SP)

Made available in DSpace on 2022-04-29T08:26:53Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-01-01 East Midlands Development Agency Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) A contaminant plume due to leachate infiltration was found in the solid waste landfill from Bauru, SP. The soil hydraulic conductivity (K) is an important parameter to understand the moving of this plume. This paper intends to show representative K values for the soils that occur in the vicinity of this landfill determined by field and laboratory tests. There are four soil types in the area: colluvium, alluvium, sandstone residual soil and the sandstone. Laboratory tests were performed using constant and variable head in rigid and flexible wall permeameters. Slug tests and hydraulic conductivity tests with the Guelph permeameter were also carried out in situ in the area. Representative K values of 3.7x10-7 m/s for the saturated zone and 2.4x10-8 m/s for the unsaturated zone were determined for the residual soil. A K value of 5.3x10-5 m/s was obtained for the colluvium soil. A great variation of K with depth was observed for the alluvium and the assumed average values for the saturated zone were 7.9x10-7 m/s and 1.1x10-4 m/s for the unsaturated surficial layer. An average K value of 3.3x10-8 m/s was determined in laboratory for the sandstone and it was assumed representative for this material. Universidade Estadual Paulista Faculdade de Engenharia de Bauru Depto. de Engenharia Civil Av., Eng. Luiz Edmundo Carrijo Coube 14-01 Universidade Estadual Paulista Faculdade de Engenharia de Bauru Depto. de Engenharia Civil Av., Eng. Luiz Edmundo Carrijo Coube 14-01 FAPESP: 2009/12764-0

Made available in DSpace on 2014-06-24T19:53:41Z (GMT). No. of bitstreams: 0 Previous issue date: 2004Bitstream added on 2014-06-25T11:47:11Z : No. of bitstreams: 1 ISSN1980-900X-2004-23-1-89-103.pdf: 1427075 bytes, checksum: d71c8fb758b89d12a0f5ca45f9b8ced7 (MD5) O ensaio de penetração do cone elétrico e do piezocone pertence a um grupo de ensaios de campo, cuja utilização vem sendo cada vez mais difundida. Tanto o avanço da eletrônica como a rápida evolução da informática têm proporcionado equipamentos mais apropriados, menores, mais robustos e mais econômicos, permitindo a incorporação de diversos sensores a essa ferramenta de investigação. Isto contribuiu para que esse ensaio se consagrasse para a descrição contínua do perfil geotécnico, a definição do nível de água e para estimativa de parâmetros mecânicos do solo. Neste artigo faz-se uma breve apresentação do piezocone e do minicone elétrico: o primeiro vem sendo utilizado nos últimos anos, especialmente em geotecnia ambiental, e o segundo, na investigação da infra-estrutura de transportes. Apresentam-se e discutem-se exemplos de emprego do piezocone para identificação de regiões do maciço contaminadas e do minicone para detectar a superfície de ruptura de uma seção de um talude de aterro, para avaliar sua estabilidade através de retroanálises. Concluise o trabalho fazendo-se algumas considerações sobre a utilização dessa tecnologia moderna e recente em solos tropicais que ocorrem no Brasil. The electrical cone penetration and piezocone testing have become increasingly popular for in situ testing in site investigation and geotechnical design. The advances in electronics and computer engineering created smaller, stronger and cheaper devices that have been incorporated to some investigation tools. It contributed for the piezocone testing to be an unequaled logging tool with respect to the delineation of stratigraphy and the continuous quick estimative of soil mechanical parameters. This paper briefly presents the piezocone and the minecone testing. At the last years the piezocone has been used as a logging tool for geo-environmental site investigation, and the mini-cone gives finer details compared to the standard cone, making it more attractive for transportation infrastructure investigation. Some cases histories, where the piezocone were used to identify zones from the soil mass contaminated by salt, and the mini-cone were used to detect failure surface to assess slope stability of a landfill based on back-analysis technique, are presented and discussed. This paper is finished with some comments about the necessity of additional research to adjust this recent and modern technology for site investigation of Brazilian tropical soils. Universidade Estadual Paulista Júlio de Mesquita Filho, Faculdade de Engenharia de Bauru, Departamento de Engenharia Civil. Universidade Estadual Paulista Júlio de Mesquita Filho, Faculdade de Engenharia de Bauru, Departamento de Engenharia Civil Universidade Estadual Paulista Júlio de Mesquita Filho, Faculdade de Engenharia de Bauru, Departamento de Engenharia Civil. Universidade Estadual Paulista Júlio de Mesquita Filho, Faculdade de Engenharia de Bauru, Departamento de Engenharia Civil