The document contains the catalog of earthquakes in Vogtland /West Bohemia within the period of 2008/10/19 -to- 2009/03/16. The events were recorded by a seismic mini-array operated by the Institute of Earthsciences, University of Postdam. / Das Dokument enthält einen Katalog von Erdbeben im Vogtland/Westböhmen im Zeitraum 2008/10/19 -bis- 2009/03/16. Die Erdbeben wurden mit Hilfe eines seismologischen Miniarrays, welches vom Institut für Geowissenschaften, Universität Potsdam, aufgestellt wurde, registriert.

Historical seismic events such as the San Fernando earthquake of 1971 and the Loma Prieta earthquake of 1989 did much to highlight the vulnerabilities in many existing highway bridges. However, it was not until 1990 that this awareness extended to the moderate seismic regions such as the Central and Southeastern United States (CSUS). This relatively long neglect of seismic issues pertaining to bridges in these moderate seismic zones has resulted in a portfolio of existing bridges with seismic deficiencies which must be assessed and addressed. An emerging decision tool, whose use is becoming ever increasingly popular in the assessment of this seismic risk, is that of seismic fragility curves. Fragility curves are conditional probability statements which give the probability of a bridge reaching or exceeding a particular damage level for an earthquake of a given intensity level. As much research has been devoted to the implementation of fragility curves in risk assessment packages, a great need has arisen for bridge fragility curves which are reliable, particularly for those in moderate seismic zones. The purpose of this study is to use analytical methods to generate fragility curves for nine bridge classes which are most common to the CSUS. This is accomplished by first considering the existing bridge inventory and assessing typical characteristics and details from which detailed 3-D analytical models are created. The bridges are subjected to a suite of synthetic ground motions which were developed explicitly for the region. Probabilistic seismic demand models (PSDM) are then generated using these analyses. From these PSD models, fragility curves are generated by considering specific levels of damage which may be of interest. The fragility curves show that the most vulnerable of all the bridge nine bridge classes considered are those utilizing steel girders. Concrete girder bridges appear to be the next most vulnerable followed by single span bridges of all types. Various sources of uncertainty are considered and tracked throughout this study, which allows for their direct implementation into existing seismic risk assessment packages.

Shape memory alloys (SMAs) are unique metallic alloys which can undergo large deformations while reverting back to their undeformed shape through either the application of heat (shape memory effect) or the removal of the load (superelastic effect). A multi-scale and multi-disciplinary approach is taken to explore the use of large diameter NiTi SMAs for applications in earthquake engineering. First, a materials characterization study is performed by studying precipitate formation, grain size and orientation, thermal transformation behavior, and strength. Cyclic tensile tests on coupon specimens and full-scale large diameter bars are then used to correlate the microstructural properties to the macroscopic behavior. Further experimental studies using NiTi wire are performed in order to optimize their properties for seismic applications. The ability of mechanical training to stabilize NiTi cyclic properties, the ability of pre-straining to increase damping levels, and the influence of different types of earthquake loadings are considered. Phenomenological mechanical models are then developed based on these results. An analytical study is then used to evaluate the performance of structural systems incorporating SMAs. One type of system evaluated includes an SMA bracing system used to modify the response of a structure during a seismic event. Overall, the results of this study have shown the ability to optimize the properties of NiTi SMAs for seismic applications through material processing. The analytical results show potential for the use of SMAs in seismic applications and provide areas for continued research.

The central focus of this dissertation is a seismic vulnerability assessment of retrofitted bridges. The objective of this work is to establish a methodology for the development of system level fragility curves for typical classes of retrofitted bridges using a probabilistic framework. These tools could provide valuable support for risk mitigation efforts in the region by quantifying the impact of retrofit on potential levels of damage over a range of earthquake intensities. The performance evaluation includes the development of high-fidelity three-dimensional nonlinear analytical models of bridges retrofit with a range of retrofit measures, and characterization of the response under seismic loading. Sensitivity analyses were performed to establish an understanding of the appropriate level of uncertainty treatment to model, assess, and propagate sources of uncertainty inherent to a seismic performance evaluation for portfolios of structures. Seismic fragility curves are developed to depict the impact of various retrofit devices on the seismic vulnerability of bridge systems. This work provides the first set of fragility curves for a range of bridge types and retrofit measures. Framework for their use in decision making for identification of viable retrofit measures, performance-based retrofit of bridges, and cost-benefit analyses are illustrated. The fragility curves developed as a part of this research will fill a major gap in existing seismic risk assessment software, and enable decision makers to quantify the benefits of various retrofits.

The lower Da-An River in western Taiwan was uplifted ~10 during the 1999 Mw 7.6 Chi-Chi earthquake, resulting in a 20- to 30-m-deep bedrock gorge. However, the amount of coseismic displacement along the channel bed does not fully explain the resulting bedrock channel incision. Using a series of aerial photographs, digital terrain models (DEM), and real-time kinematic global positioning system (RTK GPS) surveys, we characterized knickpoint retreat and fluvial incision in the Da-An River gorge. We also analyzed discharge and precipitation data and collected measurements of rock strength and joint plane orientations to understand the climatic, lithological, and structural influence on the evolution of the actively incising gorge. Two stages of fluvial incision and knickpoint migration are identified in the gorge following surface uplift during the Chi-Chi earthquake. From 1999 to 2004, 3 to 5 m of alluvium was removed from the channel bed, followed by 3 to 4 m of bedrock channel incision. The knickpoint generated immediately after the earthquake stayed where the uplift occurred at this time. Since 2005, the channel bed has lowered rapidly with local incision rate as high as 15 m/yr in terms of knickpoint migration. The average knickpoint migration rate over the period 2005 to 2009 was 238 m/yr; total upstream migration from the location of knickpoint formation was 1190 m. While tectonic uplift formed the knickpoint and set the stage for channel incision, climate played a critical role in accelerating the fluvial response to coseismic displacement. More than 20 m of bedrock channel incision and 1180 m knickpoint migration occurred during the post-2004 typhoon seasons (May-October). Based on repeat surveys of the Da-An River longitudinal profile and analysis of precipitation and discharge data, we suggest that a discharge threshold of 1200 to 2600 m³/s is required to initiate upstream knickpoint migration. However, once the threshold is exceeded, bedding dip becomes the primary control on rates and patterns of knickpoint propagation. Rotation occurred in a hinge zone where the bedding dips change from horizontal to upstream-dipping, while replacement was observed in the strata dipping upstream. The highest knickpoint migration rates (> 300 m/yr) were recorded in flat-lying, horizontal strata (< 10º) where parallel retreat was the dominate process. Overall, the knickpoint propagation followed the process of replacement behavior, in which the height of knickpoint decreases while migrating upstream. Thus, while tectonic processes set the initial conditions for knickpoint propagation in the Da-An River, the response time of the fluvial system to this forcing is strongly dependent on climate and local structure.

Container cranes represent one of the most critical components of ports worldwide. Despite their importance to port operations, the seismic behavior of cranes has been largely ignored. Since the 1960s, industry experts have recommended allowing cranes to uplift, believing that it would limit the amount of seismic loading. However, modern cranes have become larger and more stable, and the industry experts are now questioning the seismic performance of modern jumbo cranes. The main goal of this research was to experimentally investigate the seismic behavior of container cranes from the general elastic behavior through collapse, including non-linear behavior such as buckling and cross section yielding, utilizing the 6 degree-of-freedom shake tables at the University at Buffalo. The testing was divided into two phases. The first phase of testing was conducted on a 1/20th scale model. The second phase of testing was conducted on a 1/10th scale model, which was designed such that no inelastic action would develop prior to uplift (as is the common design practice). In support of the experiments, finite element models were created to determine what simplifications could be made to the structure to aid in testing. The data collected from the testing has been used to validate finite element models, to give a better understanding of the behavior of container cranes under seismic excitations, validate fragility models, and to develop recommendations and guidelines for the design and testing of container cranes.

As a consequence of the 2010 – 2011 Canterbury earthquake sequence, Christchurch experienced widespread liquefaction, vertical settlement and lateral spreading. These geological processes caused extensive damage to both housing and infrastructure, and increased the need for geotechnical investigation substantially. Cone Penetration Testing (CPT) has become the most common method for liquefaction assessment in Christchurch, and issues have been identified with the soil behaviour type, liquefaction potential and vertical settlement estimates, particularly in the north-western suburbs of Christchurch where soils consist mostly of silts, clayey silts and silty clays. The CPT soil behaviour type often appears to over-estimate the fines content within a soil, while the liquefaction potential and vertical settlement are often calculated higher than those measured after the Canterbury earthquake sequence. To investigate these issues, laboratory work was carried out on three adjacent CPT/borehole pairs from the Groynes Park subdivision in northern Christchurch. Boreholes were logged according to NZGS standards, separated into stratigraphic layers, and laboratory tests were conducted on representative samples. Comparison of these results with the CPT soil behaviour types provided valuable information, where 62% of soils on average were specified by the CPT at the Groynes Park subdivision as finer than what was actually present, 20% of soils on average were specified as coarser than what was actually present, and only 18% of soils on average were correctly classified by the CPT. Hence the CPT soil behaviour type is not accurately describing the stratigraphic profile at the Groynes Park subdivision, and it is understood that this is also the case in much of northwest Christchurch where similar soils are found. The computer software CLiq, by GeoLogismiki, uses assessment parameter constants which are able to be adjusted with each CPT file, in an attempt to make each more accurate. These parameter changes can in some cases substantially alter the results for liquefaction analysis. The sensitivity of the overall assessment method, raising and lowering the water table, lowering the soil behaviour type index, Ic, liquefaction cutoff value, the layer detection option, and the weighting factor option, were analysed by comparison with a set of ‘base settings’. The investigation confirmed that liquefaction analysis results can be very sensitive to the parameters selected, and demonstrated the dependency of the soil behaviour type on the soil behaviour type index, as the tested assessment parameters made very little to no changes to the soil behaviour type plots. The soil behaviour type index, Ic, developed by Robertson and Wride (1998) has been used to define a soil’s behaviour type, which is defined according to a set of numerical boundaries. In addition to this, the liquefaction cutoff point is defined as Ic > 2.6, whereby it is assumed that any soils with an Ic value above this will not liquefy due to clay-like tendencies (Robertson and Wride, 1998). The method has been identified in this thesis as being potentially unsuitable for some areas of Christchurch as it was developed for mostly sandy soils. An alternative methodology involving adjustment of the Robertson and Wride (1998) soil behaviour type boundaries is proposed as follows:  Ic < 1.31 – Gravelly sand to dense sand  1.31 < Ic < 1.90 – Sands: clean sand to silty sand  1.90 < Ic < 2.50 – Sand mixtures: silty sand to sandy silt  2.50 < Ic < 3.20 – Silt mixtures: clayey silt to silty clay  3.20 < Ic < 3.60 – Clays: silty clay to clay  Ic > 3.60 – Organics soils: peats. When the soil behaviour type boundary changes were applied to 15 test sites throughout Christchurch, 67% showed an improved change of soil behaviour type, while the remaining 33% remained unchanged, because they consisted almost entirely of sand. Within these boundary changes, the liquefaction cutoff point was moved from Ic > 2.6 to Ic > 2.5 and altered the liquefaction potential and vertical settlement to more realistic ii values. This confirmed that the overall soil behaviour type boundary changes appear to solve both the soil behaviour type issues and reduce the overestimation of liquefaction potential and vertical settlement. This thesis acts as a starting point towards researching the issues discussed. In particular, future work which would be useful includes investigation of the CLiq assessment parameter adjustments, and those which would be most suitable for use in clay-rich soils such as those in Christchurch. In particular consideration of how the water table can be better assessed when perched layers of water exist, with the limitation that only one elevation can be entered into CLiq. Additionally, a useful investigation would be a comparison of the known liquefaction and settlements from the Canterbury earthquake sequence with the liquefaction and settlement potentials calculated in CLiq for equivalent shaking conditions. This would enable the difference between the two to be accurately defined, and a suitable adjustment applied. Finally, inconsistencies between the Laser-Sizer and Hydrometer should be investigated, as the Laser-Sizer under-estimated the fines content by up to one third of the Hydrometer values.

No description available.

Structural evaluation and seismic vulnerability assessment of Reinforced Concrete (R/C) buildings have especially become the focus of many researches in Turkey and abroad especially after the August 17, 1999 earthquake causing major life and property losses. A devastating earthquake being expected in Istanbul-Marmara region raises many questions on how well the existing buildings are constructed and whether they can stand a major earthquake. Evaluation of existing buildings for seismic vulnerability requires time consuming input preparation (pre-processing), modelling, and post processing of analysis results. The objective of the study is to perform automated seismic vulnerability assessment of existing R/C buildings automatically over the internet by asking internet users to enter their building related data, and streamlining the modelling-analysis-reporting phases by intelligent programming. The internet based assessment tool is prepared for two levels of complexity: (a) the detailed level targets to carry out seismic evaluation of the buildings using a linear structural analysis software developed for this study / (b) the simplified level produces seismic evaluation index for buildings, based on simple and easy to enter general building information which can be entered by any person capable of using an internet browser. Detailed level evaluation program includes a user friendly interface between the internet user and analysis software, which will enable data entry, database management, and online evaluation/reporting of R/C buildings. Building data entered by numerous users over the internet will also enable formation of an extensive database of buildings located all around Turkey. 36 buildings from D&uuml / zce damage database, generated by the cooperation of Scientific and Research Council of Turkey (T&Uuml / BiTAK) and Structural Engineering Research Unit (SERU) after the 17 August 1999 Kocaeli and the 12 November 1999 D&uuml / zce earthquakes, are used in the analyses to identify relationship between calculated indices and observed damage levels of buildings, which will enable prediction of building damage levels for future earthquakes. The research is funded by Science Research Program (BAP 2003-03-03-03), NATO-SfP 977231, and TUBITAK ICTAG-I574 projects. The contribution of the research is composed of a) online building index -performance analysis/evaluation software which might be used by any average internet user, b) an ever-growing R/C building database entered by various internet users.

The functionality of the transportation network following an earthquake event is critical for post-earthquake response and long-term recovery. The likely performance of a transportation network can be evaluated through a detailed seismic risk assessment. This paper presents an assessment of the seismic risk to the transportation network in the City of Charleston and the surrounding counties to support emergency response and the development of mitigation strategies and emergency planning efforts (such as lifeline selections). This study includes an inventory analysis of the 375 bridges in the Charleston area, and convolution of the seismic hazard with fragility curves analytically derived for classes of bridges common to this part of the country, damage-functionality relationships, and replacement cost estimates using relevant region-specific data. Using state-of-the-art tools, the distribution of potential bridge damage and functionality is evaluated for several scenario events, in order to aid in the identification of emergency routes and assess areas for investment in retrofit. Additionally, a sensitivity study is conducted to determine the criticality of a few of the different input models. Initial estimates of economic losses are assessed and preliminary recommendations for prioritizing retrofit are presented.