General deformation behavior of deep excavation support systems: A review

In geotechnical engineering, ground movement caused by excavations is a challenging issue. The excessive differential settlement generated by soil movement induced by wall deflection may cause damage to nearby structures. A detailed literature review on the general deformation behavior of deep excavation support systems is presented in this paper. Many factors, such as normalized horizontal deflection (δh-max/He%), vertical displacement (δv-max/He%), δvmax/δhmax ratio, settlement influence zone (Do), etc., can play significant roles in describing the deflection behavior of the excavation system. A descriptive analysis of the reviewed data was carried out. The concluded δh-max/He% values range between 0.17 to 1.5, with a mean value of 0.58 for soft clay, while in the case of sands and stiff clay soils δh-max/He% value ranges between 0.07 to 0.40, with a mean value of 0.20. δv-max/He% values range between 0.13 to 1.10, with a mean value of 0.49 for soft soil, while its value ranges between 0.02 to 1.10, with a mean value of 0.24 in the case of sands and stiff clay soils. The settlement influence zone (Do) reaches a mean distance of 2.3He, which falls within Do=1.5-3.5He in the case of soft clays, while Do reaches a mean distance of 2.0He and 3.0He in the case of sands and other stiff clay soils, respectively. The relationship between system stiffness and excavation-induced wall and ground movements was discussed. Unfortunately, the literature review offers limited data regarding system stiffness, the 3-D nature of excavation support systems, excavation processes, and time effects.

Performance of Building with Basements Under Seismic Excitation Considering Soil Structure Interaction

In modern construction, there is a trend to go deeper below the grade level in terms of basements which can be utilized for parking, shopping malls or a combination of both. In such cases, dynamic soil properties have a significant effect of activating dynamic soil structure interaction phenomenon during earthquake. Here in present study an effort is made to study the behavior of a building by varying five and three number of basements considering dynamic soil structure interaction. Issues like influence zone to be considered for dynamic soil structure interaction, behavior of building with basements under different water level conditions for two different types of layered soil and their comparison with fixed based structure for a real-life structure is dealt with. It is observed that dynamic soil structure interaction can significantly change the behavior and also the failure pattern of the building and hence it is recommended to perform dynamic soil structure interaction for building with multiple basements.

Influence of Natural and Climatic Factors on Water Horizons Protection Degree in Site Evaluation for Radioactive Waste Disposal

In this paper, natural (geological and hydrological) and climatic impact conditions on the influence zone for two different sites of radioactive waste disposals have been studied. Probabilistic approach to assessment of the groundwater vulnerability from radionuclide contamination during disposal of radioactive waste is developed. As to climatic conditions, an effective numerical and analytical methods for annual precipitation rates assessment of rare recurrence have been proposed which allow to take into account uncertainties of rare events as well.

Dandelion Taraxacum officinale L. As a Promising Tool for Bio-Diagnostics of the State of the Urban Environment

The need to expand the list of organisms used in environmental biodiagnostics arises from the variety of pollutants and types of man-made effects on the biosphere. The choice of available test organism should be based on easily detectable and differentiable sensitivity to factors, high reproducibility of seed material, alignment of the genetic line used by the gene pool and phenotype. The paper presents the results of the soil contamination of urban agglomeration study by the bioindication and biotesting method using a dandelion as a bioindicator plant and a test organism. Within the study, the generation of dandelion was obtained and investigated for applicability in biotesting. During the first stage of the study, soil samples were taken in the influence zone of VOAO Khimprom and near the 2nd Prodol’naya avenue of Volgograd. Germination of dandelion seeds showed noticeable differences in growth rates both in comparison with control and in comparison, of prototypes with each other. At the end of the first stage, numerous apomictic seed offspring were obtained to excrete the aligned genetic lineage of test organisms. The expansion of the list of contaminated locations by counting the territories adjacent to the VMK Krasnyi Oktyabr’ showed the detected differentiated physiological reaction of test organisms grown in experimental soil samples. The results of the study confirm the postulate on soil contamination of urban locations with physiologically active pollutants and also characterize the used plant as a sensitive and easily reproducible test organism under artificial conditions. During the two-year experiment the possibility of selecting the genetic lineage Taraxacum officinale with predictable and monotonous properties was proved due to the tendency of this species to apomixis.

Effect of Bimodal Grain Structure on the Microstructural and Mechanical Evolution of Al-Mg/CNTs Composite

The Al-Mg alloy structure reinforced with carbon nanotubes was evaluated after the composites production through a modified flake metallurgy technique followed by hot extrusion. The obtained bimodal microstructure of the matrix allowed to identify the microstructural mechanisms leading to high strength; uniform elongation and strain hardening ability of the produced composites. The presence of Mg transformed the native Al2O3 layer into spinel MgAl2O4 nano-phases dispersed both inside CG and UFGs and on the interfaces, improving the interfacial bonding of Al-Al as well as Al-CNT. The effect of the reinforcing phases percentages on the dislocations mechanisms evolution was evaluated through stress relaxation tests leading to the underlying of the effect of reinforcing phases on the modification of the interphase influence zone

Málaga Costa del Sol airport and its new conceptualization of hinterland

The concept of hinterland is changing with a globalized economy, new needs between airports, stakeholders and the tourist destination challenge new dimensions of operation in the territory. Identifying new factors and actors in the influence zone of the hinterland will allow us to stage the importance of airports in the regional economy and the positive effects derived from these. The aim of this paper is to analyse the hinterland of Málaga Costa del Sol airport and its territorial and economic dimensions. Moreover, to provide an updated and clearer definition of hinterland, assuming future implications for airport operators, management of tourist destination by destination marketing organizations and scholars and practitioners interested in this topic. The results revealed that Málaga’s airport is modifying the hinterland of airport and its area of influence in economic and urban development terms.