Abstract

The design and construction of structures in seismic areas requires knowledge of the seismic actions to which they can be subjected throughout their useful life. In general, it is not enough to establish what would be the maximum acceleration which could act upon the structure to be designed, but, in addition, the frequency with which the seismic phenomenon occurs and the damage it would produce should be known. In this monograph the probability of occurrence of earthquakes is studied regardless of the type of structure, of the population of the area, of the industrial level of the same, for the northeast area of ​​the Iberian Peninsula; the results obtained are reflected in maps. The study is restricted to finding the probabilities of occurrence of earthquakes classified by their intensity (epicentral or felt) and, in spite of the approximation due to the use of the intensities, the results will be of great value for the making of design decisions. The methods for evaluating these probabilities of intensity occurrence are very varied, but basically there are two different conceptions of the methods of calculation: the deterministic methods and the probabilistic ones. The deterministic methods start from the recorded earthquakes and evaluate the effects of these using different coefficients. The probabilistic methods do not directly use the recorded earthquakes, but these data serve to establish certain laws of probability of occurrence that give rise to regional or zonal models of occurrence. The method presented herein has elements of both approaches, although always in the context of Bayesian statistics and is adapted to the special conditions of the northeast of the Iberian Peninsula or other areas where data are scarce and seismicity is moderate.

Abstract

Saline intrusion is a critical issue in building material because of the severe damages caused by the salt precipitation/dissolution process, especially for the porous material, which has good connectivity. When porous material is exposed to aggressive ambient, the pore structure, not only porosity but also pore size distribution, will be altered by salt precipitation/dissolution. As one of the most significant characteristics in the porous material, pore size distribution is always paid much attention in many literatures. However, a quantitative and practical determination method is still absent. This work aims to establish a probabilistic model to investigate the pore size distribution induced by solid-phase precipitation/dissolution. First, a lognormal distribution is proposed for the simulation of initial pore size distribution tested by the MIP method. Then we develop a probabilistic-based porous network to represent the evolution of microstructure due to precipitation/dissolution. To this end, two different transformation models are constructed to interpret the relation between initial pore radius and modified pore radius before and after precipitation/dissolution. With this probabilistic-based porous network, we could illustrate the precipitated profiles that evolve near the capillary interface during the salt precipitation/dissolution process for a given porosity and water saturation degree. Such a method could be used to interpret the mechanism of the local precipitation/dissolution process in pore scales, which cannot be implemented by experimental measurements.