Seismic Microzoning Method with using procedures by spectrum ratio H/V

This study investigated the hydraulic properties of the heterogeneous aquifers of an artificial island (Yunlin Offshore Industrial Park) in Taiwan. The research was based on the groundwater level response affected by tidal fluctuation using the hydraulic tomography (HT) to analyze the hydraulic diffusivity (α). Specifically, the power spectrum ratio of groundwater and tidal fluctuations derived from the Gelhar solution was used to estimate α in homogeneous aquifers; this, however, could not be applied in the artificial island. Next, the spatial distribution of the groundwater level response affected by tidal fluctuation was analyzed and found to be irregular, proving the existence of hydrogeological heterogeneity in the artificial island. Furthermore, the results of the estimated α using the HT showed low error and high correlation, 0.41 m2/hr and 0.83, respectively, between the optimal estimated heterogeneous and reference α fields in the synthetic aquifer. Last, the HT was used in the real tested scenario. By comparing the predicted groundwater levels of the optimal estimated heterogeneous α field and the observed groundwater levels of the real aquifer, it was found that the correlation was higher than 0.99. Therefore, the HT can be used to obtain the optimal estimated heterogeneous α field in the artificial island.

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Seismic microzoning in New Zealand

Bulletin of the New Zealand Society for Earthquake Engineering ◽

10.5459/bnzsee.4.1.43-50 ◽

1971 ◽

Vol 4 (1) ◽

pp. 43-50

Author(s):

W. R. Stephenson

Keyword(s):

New Zealand ◽

Structural Damage ◽

Seismic Waves ◽

Multiple Reflection ◽

Ground Failure ◽

Seismic Microzoning ◽

Popular View ◽

Wave Trains ◽

Local Geology ◽

Ground Damage

"Seismic Microzoning" means many different things to different people. There is always included the element of different damage in nearby areas, but how the differences arise, how we should study them, and how we should apply the results of our studies, are still uncertain. To some people, microzoning refers to structural damage due to ground failure; faulting, slumping and liquefaction all belong in this category. To others, microzoning is the effects of the focussing of seismic waves by boundaries, resulting in modified ground damage and building damage. A third very popular view of microzoning holds that it concerns multiple reflection of seismic waves in layers, with interference of the wave trains giving rise to maxima, where ground and structural damage will be accentuated. Microzoning can be defined as the division of land areas into small regions of differing local geology for which differences in earthquake attack on structures are specified. This paper is an attempt to set down aspects of microzoning in a logical manner, and to relate them. It also discusses activities here and overseas, and considers where microzoning and microzoning research in New Zealand should head.

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DESING SPECTRUMS FOR THE CENTRAL NORTH OF QUI-TO AND SEISMIC ANALYSIS OF STEEL STRUCTURES USING THE CAPACITY SPECTRUM METHOD.

Revista Sul-americana de Engenharia Estrutural ◽

10.5335/rsee.v12i3.5222 ◽

2014 ◽

Vol 12 (3) ◽

Author(s):

Roberto Rodrigo Aguiar

Keyword(s):

High School ◽

Steel Structures ◽

Capacity Spectrum Method ◽

North Central ◽

Seismic Microzoning ◽

Spectrum Method ◽

Performance Point ◽

Capacity Spectrum ◽

Elastic Response Spectra ◽

The City

The city of Quito lies on geological faults that have no surface outcrop but are moving with a speed of 2-4 mm per year. The last strong earthquake associated with these thrust faults, was rec-orded in 1587 and had a magnitude of 6.4; so it has been more than 400 years, there is a large amount of stored energy, and the probability of an earthquake occurring is very high. Therefore, this article presents, firstly, the periods of recurrence of these faults; then a microzoning of the north central part of the city and the elastic response spectra for 5% damped associated to the Llumbisi- La Bota segment fault, ILB. And subsequently, an analysis of nine steel structures from one to nine storeys assuming that they are situated in the following three areas of north central Quito: the old Quito Tenis; La Gasca and Benalcazar High School. Using the Capacity Spectrum Method MEC, the seismic response is found with the presence of three spectrums as prescribed in the Ecuadorian Construction Regula-tions NEC-11; the recommendation in the study of the seismic microzoning of Quito ERN-12 and those found in the seismic microzoning associated with the fault ILB. Three types of responses are indicated for each location, the structures situated in the old Quito Tenis present a performance point found using the Capacity Spectrum Method MEC; for those in La Gasca, a maximum lateral displacement is indicated in each storey; and the structures situated in the Benalcazar High School present maximum interstorey drifts. It should be highlighted that the lateral displacements and interstorey drifts are reaching the end of their performance, thus the conclusions to be found in this study about which spectrum the maximum response has could be inferred from any of the three structural parameters.

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Assessment of initial seismic impacts on the northern part of the Barents Sea shelf (Novaya Zemlya region) for the purpose of seismic microzoning in the areas of prospective hydrocarbon mining

Геоэкология Инженерная геология Гидрогеология Геокриология ◽

10.31857/s0869-78092019238-47 ◽

2019 ◽

pp. 38-47

Author(s):

I. G. Mindel ◽

B. A. Trifonov ◽

M. D. Kaurkin ◽

V. V. Nesynov

Keyword(s):

Oil And Gas ◽

Barents Sea ◽

Arctic Shelf ◽

The Arctic ◽

Russian Arctic ◽

Seismic Microzoning ◽

Novaya Zemlya ◽

The Barents Sea ◽

National Task ◽

Seismic Impacts

In recent years, in connection with the national task of developing the Arctic territories of Russia and the perspective increase in the hydrocarbon mining on the Arctic shelf, more attention is being paid to the study of seismicity in the Barents Sea shelf. The development of the Russian Arctic shelf with the prospect of increasing hydrocarbon mining is a strategically important issue. Research by B.A. Assinovskaya (1990, 1994) and Ya.V. Konechnaya (2015) allowed the authors to estimate the seismic effects for the northern part of the Barents Sea shelf (Novaya Zemlya region). The paper presents the assessment results of the initial seismic impacts that can be used to solve seismic microzoning problems in the areas of oil and gas infrastructure during the economic development of the Arctic territory.

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