Search results for " Geology"

Rockburst induced ground motion—a comparative study

2004

Abstract While rockbursts from underground copper mining in Western Poland normally produce surface peak ground accelerations (PGA) and velocities of 0.05–0.1 g and 1–3 cm/s, occasionally these peak motions may exceed 0.15 g and 10 cm/s, respectively. These larger motions are of considerable concern and an investigation has been undertaken to define the nature of these larger induced ground motions. This paper compares these rockburst motions with low intensity earthquakes. Various strong motion parameters such as PGA, peak ground velocity (PGV) and displacements as well as strong motion duration, Arias intensity, Fourier and response spectra are compared with those from earthquakes. It is …

The Soil Erosion Risk Map of the Sicilian Region (1:250,000 Scale)

2014

Assessing the risk areas of soil erosion by water at the regional level is relevant for current and future land planning of environmental actions to combat land degradation. The gravity of the risk is not only depending on the rate of soil erosion by water, but also on other factors, primarily soil depth and rock weatherability. The map of the soil erosion risk in the Sicilian region, expressed in terms of years to a complete loss of the fertile soil cover, is here presented as a methodological model. The degree of risk was not only estimated in function of the rate of soil erosion by water, but also of the depth of the fertile part of the profile, and of the weatherability degree of the un…

Experimental determination of viscous damper parameters in low velocity ranges

2017

In the last decades many strategies for seismic vulnerability mitigation of structures have been developed through analytical studies and experimental tests. Among these, energy dissipation by external devices assumes a great relevance for the relative design simplicity, even if applied to complex structures, and the effectiveness in reducing seismic demand. In particular, the use of fluid viscous dampers represents a very attractive solution because of their velocity-dependent behaviour and relatively low costs. The application on structures requires specific study under seismic excitation and a particular care of structural details. In this context the use of proper constitutive models fo…

A macro-modelling approach for the analysis of infilled frame structures considering the effects of openings and vertical loads

2015

During the last decades, several macro-models have been proposed for the modelling of the infill panels' contribution to the lateral strength of frames. Despite all this effort, a robust model, which takes into account the influence of the vertical load, is not yet available. Furthermore, the influence of the very common case of infill walls with openings, such as windows and doors, has been neglected in all the code provisions that have been published so far. In this paper, an updated macro-model, based on the equivalent pin-jointed diagonal compressive strut, is presented. The proposed macro-model is able to represent the stiffening effect of the infill panel with openings by taking into …

Stress-strain models for normal and high strength confined concrete: Test and comparison of literature models reliability in reproducing experimental…

2017

SUMMARY: The adoption of proper constitutive laws for confined concrete is basic for seismic assessment of new and existing reinforced concrete civil structures. The deformation capacity of reinforced concrete (RC) columns subjected to axially centred and eccentric loads depends on the effectiveness confinement action. A proper assignment of the stressstrainlaws for concrete allows obtaining an adequate definition of the ductility of the crosssections and correctly identifying mechanical nonlinearities in computational models.Several studies concerning the behaviour of confined concrete have been carried out, highlighting the role of different geometrical and mechanical parameters to the ov…

Large-scale glaciotectonically-deformed Pleistocene sediments with deformed layers sandwiched between undeformed layers, Baltmuiža site, Western Latv…

2018

Injection structures and load casts in lagoon sediments (Sārnate outcrop, W Latvia)

2018

Litter contribution to soil organic carbon in the processes of agriculture abandon

2015

The mechanisms of litter decomposition, translocation and stabilization into soil layers are fundamental processes in the functioning of the ecosystem, as they regulate the cycle of soil organic matter (SOM) and CO2 emission into the atmosphere. In this study the contribution of litters of different stages of Mediterranean secondary succession on carbon sequestration was investigated, analyzing the role of earthworms in the translocation of SOM into the soil profile. For this purpose the δ13C difference between meadow C4-C soil and C3-C litter was used in a field experiment. Four undisturbed litters of different stages of succession (45, 70, 100 and 120 since agriculture abandon) were colle…

Las ramblas valencianas: algunos aspectos de hidrología, geomorfología y sedimentología

1987

Effectiveness of isolated vertical extension of masonry buildings as nonconventional TMD

2023

In this paper, the strategy of Intermediate Isolation System (IIS) is proposed for the vertical extension of an aggregate of masonry buildings located in Pozzuoli, south Italy. The effectiveness of IIS working as a nonconventional Tuned Mass Damper (TMD) for the existing construction is assessed in terms of reduction of seismic demand and damage in the masonry structure undergoing inelastic deformation under seismic input. For this aim, a general step-by-step procedure is first defined and then applied to the case study building. In particular, the characterization of dynamic behaviour and seismic capacity of the building aggregate is first addressed through modal and push over analyses. El…