scholarly journals Earthquake resistant design of foundations

1996 ◽  
Vol 29 (3) ◽  
pp. 155-171 ◽  
Author(s):  
M. J. Pender
Keyword(s):  
Soil Properties ◽  
State Of The Art ◽  
Deep Foundations ◽  
Foundation Design ◽  
Analysis Techniques ◽  
Current State ◽  
Earthquake Resistant Design ◽  
Earthquake Resistant ◽  
Structural Engineers ◽  
Potential Use

This paper reviews the main issues to be addressed in the design of shallow and deep foundations which may be subject to earthquake loading. Information is presented on the soil properties required as well as the various design analysis techniques with a view to assessing the current state-of-the-art and highlighting areas in which further techniques need to be developed. The paper sets out, by way of an overview, a sequence of steps that a designer may follow in developing a foundation system. It is concluded that, at present, the greatest deficiencies lie in the areas of most potential use to designers. A secondary aim of the paper is to enhance communication between geotechnical and structural engineers on aseismic foundation design.

Proposal of orientation-independent measure of intensity for earthquake-resistant design

2021 ◽  
pp. 875529302110382
Author(s):  
Alan Poulos ◽  
Eduardo Miranda
Keyword(s):  
United States ◽  
Ground Motion ◽  
The United States ◽  
Design Codes ◽  
Intensity Measure ◽  
Independent Measure ◽  
Earthquake Resistant Design ◽  
Earthquake Resistant ◽  
Ground Motion Records ◽  
Structural Engineers

A new measure of ground motion intensity in the horizontal direction is proposed. Similarly to other recently proposed measures of intensity, the proposed intensity measure is also independent of the as-installed orientation of horizontal sensors at recording stations. This new measure of horizontal intensity, referred to as MaxRotD50, is defined using the maximum 5%-damped response spectral ordinate of two orthogonal horizontal directions and then computing the 50th percentile for all non-redundant rotation angles, that is, the median of the set of spectral ordinates in a range of 90°. This proposed measure of intensity is always between the median and maximum spectral ordinate for all non-redundant orientations, commonly referred to as RotD50 and RotD100, respectively. A set of 5065 ground motion records is used to show that MaxRotD50 is, on average, approximately 13%–16% higher than Rot50 and 6% lower than RotD100. The new measure of intensity is particularly well suited for earthquake-resistant design where a major concern for structural engineers is the probability that the design ground motion intensity is exceeded in at least one of the two principal horizontal components of the structure, which for most structures are orthogonal to each other. Currently, design codes in the United States are based on RotD100, and hence using MaxRotD50 for structures with two orthogonal principal horizontal components would result in a reduction of the ground motion intensities used for design purposes.

Which Earthquakes are Expected to Exceed the Design Spectra?

2019 ◽  
Vol 35 (3) ◽  
pp. 1465-1483 ◽  
Author(s):  
Iunio Iervolino ◽  
Massimiliano Giorgio ◽  
Pasquale Cito
Keyword(s):  
State Of The Art ◽  
National Level ◽  
Seismic Events ◽  
Maximum Magnitude ◽  
Probabilistic Measure ◽  
Design Spectra ◽  
Earthquake Resistant Design ◽  
Safety Margins ◽  
Earthquake Resistant ◽  
Elastic Design

Extended recording coverage of contemporary seismic events allows a comparison of observed seismic actions with their counterparts used for design. Said comparison shows actions systematically exceeding design spectra. This paper discusses: (1) that considered exceedances can be anticipated by the probabilistic seismic hazard on the basis of which design actions are determined, (2) exceedances of elastic design actions are expected for earthquakes occurring close to the site even if their magnitude is far from the maximum magnitude considered in the hazard assessment, and (3) design spectra are likely to be exceeded in epicentral areas of earthquakes that occur frequently in the region where the code is enforced, but rarely occur close to the site under consideration. In fact, code-mandated protection against these earthquakes is factually warranted by the rarity with which they are expected to occur near the structure and other safety margins implicit to earthquake-resistant design. All these issues, addressed with reference to Italy, are discussed with the intent not to criticize the way spectra are determined, but rather to raise awareness and give a probabilistic measure about what to factually expect from state-of-the-art design at a national level.

scholarly journals Seismic Response of Large span slab in Horizontal Setback Building

2021 ◽  
Vol 9 (11) ◽  
pp. 1353-1360
Author(s):  
Manish Kumar Pandey
Keyword(s):  
Structural Elements ◽  
Commercial Building ◽  
Flat Slab ◽  
Large Span ◽  
Earthquake Resistant Design ◽  
Earthquake Resistant ◽  
Different Types ◽  
Waffle Slab ◽  
Earthquake Zone ◽  
Structural Engineers

Abstract: The demand for multi-storey buildings is increasing day by day. Residential plus commercial building is mainly used for wide span needs. Wide span required for Flat slab, Waffle slab and ribbed slab stands An excellent option for architects when larger openings in a building need to be covered with as few columns as possible. The use of different types of plates is developing as a new trend and is becoming a major challenge for structural engineers. Therefore, it is necessary to study about its structural behavior. The project is carried out under earthquake zone III under the earthquake analysis of G+9 storey building. For this study, four different types of large span slab structure are modelled in C-shape (Horizontal Setback Building) having 10-stories i.e. G+9 storied buildings with 3.50 meters height for each story is modelled and analysed. The plan area of all four buildings is same i.e. 2859 square meters (49.50 m x 82.50 m) each. These buildings were designed in compliance with the Indian Code of Practices for earthquake resistant design of buildings. Base of the building were fixed. The square sections are used for structural elements. The height of the buildings is considered constant throughout the structure. The buildings are modelled using ETABSvr.2016. Keywords: large span slab, ETABSvr.2016, Horizontal Setback Building, Flat slab, Waffle slab and ribbed slab

Earthquake Resistant Design

2019 ◽  
pp. 201-221
Author(s):  
Md. Farrukh ◽  
Nadeem Faisal ◽  
Kaushik Kumar
Keyword(s):  
Natural Disasters ◽  
Large Scale ◽  
Optimization Techniques ◽  
Human Existence ◽  
Foundation Design ◽  
Earthquake Resistant Design ◽  
Earthquake Resistant ◽  
History Of ◽  
Resistance Structure ◽  
Important Progress

In the long history of mankind's existence, nature's forces have influenced human existence to a great extent. Of all natural disasters, the least understood and most destructive are earthquakes. Their claim of human lives and material losses constantly force people to search for better protection, still a great challenge for engineers and researchers worldwide. Although important progress has been done in understanding seismic activity and developing buildings technology, a better way of protecting buildings on large scale is still in search. The essential features of earthquake resistance structure are stable foundation design, regularity, ductility, adequate stiffness, redundancy, and ruggedness. The chapter focuses on increasing the knowledge dictum of earthquake resistant design and discusses the various sorts of issues and challenges. It also presents a wide view on optimization techniques that are required to be done in the latest technology currently in practice so as to achieve the optimum design techniques.

Review : Bacteriocinogenic lactic acid bacteria associated with meat products / Revisión: Bacterias lácticas productoras de bacteriocinas asociadas a productos cárnicos

1998 ◽  
Vol 4 (3) ◽  
pp. 141-158 ◽  
Author(s):  
M.T. Aymerich ◽  
M. Hugas ◽  
J.M. Monfort
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
State Of The Art ◽  
Meat Products ◽  
Meat Consumption ◽  
Genetic Characteristics ◽  
Current State ◽  
Potential Use

Meat consumption is of great economical importance. Several lactic acid bacteria associated with meat products are important natural bacteriocin producers. Bacteriocins are proteinaceous antag onistic substances considered to be important in the control of spoilage and pathogenic microor ganisms. This review aims to present the current state of the art in terms of bacteriocinogenic lactic acid bacteria associated with fresh and fermented meat products, describe the biochemical and genetic characteristics of their bacteriocins and the potential use of bacteriocins production of meat products.

scholarly journals Magnetotactic Bacteria and Magnetosomes: Basic Properties and Applications

2021 ◽  
Vol 7 (6) ◽  
pp. 86
Author(s):  
Kamil G. Gareev ◽  
Denis S. Grouzdev ◽  
Petr V. Kharitonskii ◽  
Andrei Kosterov ◽  
Veronika V. Koziaeva ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Biomedical Applications ◽  
State Of The Art ◽  
Rock Magnetism ◽  
Magnetotactic Bacteria ◽  
Resonance Imaging ◽  
Current State ◽  
Magnetite Fe3o4 ◽  
High Degree ◽  
Potential Use

Magnetotactic bacteria (MTB) belong to several phyla. This class of microorganisms exhibits the ability of magneto-aerotaxis. MTB synthesize biominerals in organelle-like structures called magnetosomes, which contain single-domain crystals of magnetite (Fe3O4) or greigite (Fe3S4) characterized by a high degree of structural and compositional perfection. Magnetosomes from dead MTB could be preserved in sediments (called fossil magnetosomes or magnetofossils). Under certain conditions, magnetofossils are capable of retaining their remanence for millions of years. This accounts for the growing interest in MTB and magnetofossils in paleo- and rock magnetism and in a wider field of biogeoscience. At the same time, high biocompatibility of magnetosomes makes possible their potential use in biomedical applications, including magnetic resonance imaging, hyperthermia, magnetically guided drug delivery, and immunomagnetic analysis. In this review, we attempt to summarize the current state of the art in the field of MTB research and applications.

scholarly journals Detailed State of the Art Review for the Different Online/Inline Oil Analysis Techniques in Context of Wind Turbine Gearboxes

2011 ◽  
Vol 133 (4) ◽  
Author(s):  
Andrew Hamilton ◽  
Francis Quail
Keyword(s):  
Wind Turbine ◽  
Asset Management ◽  
State Of The Art ◽  
Energy Industry ◽  
Electrical Fields ◽  
Analysis Techniques ◽  
Current State ◽  
Main Driver ◽  
Size Accuracy ◽  
Different Characteristics

The main driver behind developing advanced condition monitoring (CM) systems for the wind energy industry is the delivery of improved asset management regarding the operation and maintenance of the gearbox and other wind turbine components and systems. Current gearbox CM systems mainly detect faults by identifying ferrous materials, water, and air within oil by changes in certain properties such as electrical fields. In order to detect oil degradation and identify particles, more advanced devices are required to allow a better maintenance regime to be established. Current technologies available specifically for this purpose include Fourier transform infrared (FTIR) spectroscopy and ferrography. There are also several technologies that have not yet been or have been recently applied to CM problems. After reviewing the current state of the art, it is recommended that a combination of sensors would be used that analyze different characteristics of the oil. The information individually would not be highly accurate but combined it is fully expected that greater accuracy can be obtained. The technologies that are suitable in terms of cost, size, accuracy, and development are online ferrography, selective fluorescence spectroscopy, scattering measurements, FTIR, photoacoustic spectroscopy, and solid state viscometers.

scholarly journals Earthquake Response of Cold-Formed Steel-Based Building Systems: An Overview of the Current State of the Art

Buildings ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 228 ◽  
Author(s):  
Gianmaria Di Lorenzo ◽  
Attilio De Martino
Keyword(s):  
State Of The Art ◽  
Physical Stability ◽  
Earthquake Response ◽  
Structural Systems ◽  
General Introduction ◽  
Ongoing Research ◽  
Current State ◽  
Earthquake Resistant ◽  
Building Systems ◽  
Cold Formed Steel

Building systems fabricated with cold-formed steel (CFS) profiles and members made of wood, gypsum, or other materials allow solving a range of issues arising in common constructional elements thanks to their advantages, such as lightness, strength, durability, physical stability, sustainability, and cost-effectiveness. As a result of this inherent competitiveness of CFS based buildings, their use has been gradually increasing in recent years both in the field of structural systems as non-structural architectural components and, above all, in the area of earthquake resistant buildings, where lightness play a key role. After a general introduction, the paper gives an overview of the current codification and ongoing research on CFS non-structural architectural and structural systems. Finally, the main conclusions are summarised, and possible future developments are outlined.

Exploring the Potential Use of GFRP Bars in Earthquake-Resistant Concrete Structures

2019 ◽  
Author(s):  
Hayato Auman ◽  
Alessando Palermo ◽  
Victoria Worner ◽  
Allan Scott
Keyword(s):  
Concrete Structures ◽  
Gfrp Bars ◽  
Earthquake Resistant Design ◽  
Earthquake Resistant ◽  
Frp Reinforcement ◽  
And Behavior ◽  
The University ◽  
Corrosion Of Steel ◽  
Potential Use ◽  
Seismic Applications

<p>The corrosion of steel reinforcement is a persistent issue plaguing concrete structures today. The availability of non-corrodible fiber-reinforced polymer (FRP) reinforcement presents an opportunity to mitigate or even eliminate the issue of corrosion, however there is minimal uptake of these bars specifically in seismic applications due to their brittleness. Glass FRP (GFRP) bars, being one of the more common and economical of the FRP products, is being explored at the University of Canterbury for its potential use in earthquake- resistant design. In particular, the cyclic bond of GFRP bars with concrete is being tested using a modified RILEM beam bond test to determine whether they are able to maintain adequate bond with concrete under seismic loading. This paper will discuss the potential use of GFRP bars in seismic applications, drawing form work around the world, and introduce the salient features and behavior of cyclic bonding of GFRP bars as preliminary observations from the bond tests conducted.</p>

scholarly journals Detailed State of the Art Review for the Different On-Line/In-Line Oil Analysis Techniques in Context of Wind Turbine Gearboxes

2011 ◽  
Author(s):  
Andrew Hamilton ◽  
Francis Quail
Keyword(s):  
Wind Turbine ◽  
Asset Management ◽  
State Of The Art ◽  
Electrical Fields ◽  
Analysis Techniques ◽  
Current State ◽  
Main Driver ◽  
Size Accuracy ◽  
On Line ◽  
Different Characteristics

The main driver behind developing advanced condition monitoring (CM) systems for the wind energy industry is the delivery of improved asset management regarding the operation and maintenance of the gearbox and other wind turbine components and systems. Current gearbox CM systems mainly detect faults by identifying ferrous materials, water and air within oil by changes in certain properties such as electrical fields. In order to detect oil degradation and identify particles, more advanced devices are required so allow a better maintenance regime to be established. Current technologies available specifically for this purpose include Fourier Transform Infrared (FTIR) spectroscopy and ferrography. There are also several technologies that have not yet been or have been recently applied to CM problems. After reviewing the current state of the art, it is recommended that a combination of sensors would be used that analyse different characteristics of the oil. The information individually would not be highly accurate but combined, it is fully expected that greater accuracy can be obtained. The technologies that are suitable in terms of cost, size, accuracy and development are online ferrography, selective fluorescence spectroscopy, scattering measurements, FTIR, photoacoustic spectroscopy and solid state viscometers.

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