University “SS Cyril and Methodius” Institute of Earthquake Engineering and Engineering Seismology Skopje, Republic of North Macedonia (original) (raw)

This thesis presents an investigation of different codes, methodology and techniques used in different countries with the aim to define an appropriate concept for rehabilitation of existing buildings. Chapter 2 is focused on the seismicity of Albania as a country with a high rate of seismicity in which earthquake risk reduction has been an important, on-going socioeconomic concern. A revised catalogue of Albanian earthquakes, from 58 A.D. to 2000, with magnitude Ms>4.5 in the region between 39/N and 43/N and 18.5/E and 21.5/E was used in this study. Ten seismic source zones were used to define the seismicity. The four spectral parameter maps allowed the construction of site-specific Uniform Hazard Spectra for all of Albania and were suggested as the basis of the next version of the KTP-N.2-89 Technical Seismic Regulations to improve earthquake-resistant design code in Albania. In Chapter 3 seismic design requirements or levels are the intended post-earthquake condition of a building; a well-defined point on a scale measuring how much loss is caused by earthquake damage. In addition to casualties, loss may be expressed in terms of property and operational capability. The seismic performance requirement must be achieved through system selection, detailing requirements, design force levels, and permissible drift, based on the Seismic Design Code, considering also the use of the building and the seismicity of the region containing the building site together with the effect of the site conditions. Once the energy demand for a structure is estimated from the earthquake ground motion, the damage potential must be quantified by a combination of response and energy parameters according to Park and Ang, 1985. Within the scope of a specific project the investigation was basically devoted to development of a practical and consistent methodology for structural state diagnosis. Basically, the development procedure is regarded as a specific tool which will provide successful identification of the basic parameters needed for elaboration of an optimal project for revitalization of the structural system, and it is predominantly based on application of the experimental non-destructive tests studied in chapter 5. Chapter 6 is focused on measures for improvement of structural systems in order that they will be capable to withstanding the expected earthquake effects. Decay of the building is usually consequence of weather condition, load effects and foundation settlement, so, building should be safe under normal load and resist the lateral loads without collapse. The types of intervention necessary to enhance the performance of the building can be broadly grouped under the following three categories - Repair, Restoration and Strengthening. Chapter 7 explores a method for damage assessment, in which the mathematical model of an existing building gives the level of damage index. The fragility curves developed inhere represent one of the possible forms of the earthquake intensity – damage to structures relationship. A random point on the fragility curve shows the conditional probability that the damage under an earthquake of a given intensity will exceed a certain damage state.