Society for Earthquake and Civil Engineering Dynamics
SECED 2015 was a two-day conference on Earthquake and Civil Engineering Dynamics that took place on 9-10th July 2015 at Homerton College, Cambridge.
This was the first major conference to be held in the UK on this topic since SECED hosted the 2002 European Conference on Earthquake Engineering in London.
The conference brought together experts from a broad range of disciplines, including structural engineering, nuclear engineering, seismology, geology, geotechnical engineering, urban development, social sciences, business and insurance; all focused on risk, mitigation and recovery.
SECED 2015 featured the following keynote speakers (affiliations correct at the time of the conference):
SECED allows the self-archiving of the Author Accepted Manuscripts (AAM) from the SECED 2015 Conference. This means that all authors can make their conference paper available via a green open access route. The full text of your paper may become visible within your personal website, your institutional repository, a subject repository or a scholarly collaboration network signed up to the voluntary STM sharing principles. It may also be shared with interested individuals, for teaching and training purposes at your own institution and for grant applications (please refer to the terms of your own institution to ensure full compliance).
To deposit your AAM, please adhere to the following conditions:
SECED allows authors to deposit their AAM under the Creative Commons Attribution Non-commercial International Licence 4.0 (CC BY-NC 4.0). The deposit must clearly state that the AAM is deposited under this licence and that any reuse is allowed in accordance with the terms outlined by the licence. To reuse the AAM for commercial purposes, permission must be sought by contacting firstname.lastname@example.org. For the sake of clarity, commercial usage would be considered as, but not limited to:
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When a structure is subjected to a very short lived impact or blast at one location, a pulse of energy is transmitted through the structure. This energy pulse manifests itself as displacement, velocity and acceleration within the structure. The overall effect is known as In Structure Shock (ISS). Although this shock has a very short duration and is attenuated as it passes through the structure, it theoretically has the potential to disrupt equipment resting on or anchored to the building structure. The paper will examine how to deal with such shock transmission, using the example of a facility built from multi-cellular concrete shear walls. The findings are applicable to all high hazard facilities where such shock transmission can occur.
The paper will examine how the effects of shock loading may be modelled within the building. It will compare and contrast the techniques available for shock loading with those commonly used for seismic loading, and discusses the differences associated with the extremely short duration of loading.
The use of spectra for shock typically shows significant accelerations for frequencies greater than 20Hz; with very high accelerations (many multiples of g) at the peak, which is in the region of 100 to 300 Hz. The dynamic deflections associated with these accelerations are small (typically less than 1mm) at frequencies of 15 to 25 Hz, with even smaller deflections at higher frequencies. The paper will discuss how these effects can be allowed for. The consequence of these high strain rates on material properties will also be considered.
The duration of the pulse is of the order of 10 ms to 100 ms. In this timescale the energy absorbed is small, and as such, if the structure system or component (SSC) was to yield and a mechanism form, then only a very limited amount of plastic deformation would occur. Collapse would only occur if a brittle fracture occurred in the few milliseconds of the pulse. In this time scale, even failure from conventional brittle failure modes such as buckling and shear will not occur in steel. Failure modes are limited to components shaking loose; failure of brittle materials; and other similar modes.
Based upon the above, the paper will examine for the structure in question, a number of different techniques that were adopted to deal with the various SSCs. These were:
Comparison with seismic spectra
Use of shock fragility data in accordance with UFC 3-340-01, 2002
Provision of vibration isolation