Designing of Radioactive Waste Disposal Objects
Applying of Spectral Seismic Methods at Designing of Radioactive Waste Disposal Objects
Tech Area / Field
- ENV-SEM/Seismic Monitoring/Environment
- ENV-WDS/Waste Disposal/Environment
- OTH-BIT/Building Industry Technology/Other
3 Approved without Funding
VNIPI Promtechnology, Russia, Moscow
- Institute of Dynamics of the Geosphere, Russia, Moscow
- Lawrence Livermore National Laboratory, USA, CA, Livermore
Краткое описание проектаThe purpose of the present project is making the methodical recommendations at definition of rocky massif state by seismic methods at designing building of important facilities with a long operative life - such as facilities of radioactive waste (RW) disposal.
Traditionally used in prospecting operations the seismic methods expect to obtain the input data about speed characteristics of building sites and spectral characteristics of a massif, which one are most relevant at an estimation of stability of designed facilities to exterior affecting
In the present project the new approach is offered applying of spectral methods for definition of massif disturbance extent at carrying out prospecting operations by seismic methods.
It is the seismic resonance method and method of spectral relaxation.
The proposed approach will allow essentially increase quality of prospecting operations at the expense of definition of a spatial distribution of amplitude - spectral characteristic of micro seismic vibrations, definition of a series of geodynamic parameters of environment describing mechanical stability of local areas.
It enables to rank areas on predicting a level of long-time mechanical stability and conservation of bearing capacities of the foundation at a choice of places for building of rather accountable objects of heightened risk, and also carrying out of constant check of foundation state at geodynamic control of long-time secure operation of such objects.
The pointed methods were designed by VNIPIPT and IDGRAS employes for the purposes of check of underground nuclear detonations trials and diagnostic of a geodynamic state of earth crust areas intended for building of RW underground disposal and underground nuclear reactors of APP and heat supply of northern cities of Russia.
It is doubtless that the applying of these methods with the purpose of eliciting heterogeneities of earth crust and anomalies of geodynamic processes in region of building of accountable objects essentially will rise veracity and reliability of input data used in designing.
The widely now in use methods of analysis of near-surface natural structures based on discrete measuring of mechanical parameters in separate posts, do not allow to obtain complete pattern of behavior of complicatedly structured geologic environment.
The block structure and presence of the expressed miscellaneous oriented moves of inpidual and consolidated blocks results to mosaic, spatially inhomogeneous allocation of the basic mechanical characteristics of environment.
For deriving the detailed dimensional description of geologic environment behavior in the present Project the new approach based on registrations and analysis of seismic vibrations of a domestic genesis is used. This approach allows encompassing an investigated area of earth crust as a whole with simultaneous registration of the information incoming from its each structural part.
On the basis of detailed analysis of amplitude and spectral characteristics of microoscillatings including background component and impulses of a relaxational type the block structure of environment, level of active blocks movability and also the zones of abnormal tight - strained state are located. The outcomes allow carrying out the comparative characteristics of investigated local areas of earth crust. The relevant positive quality of the pointed approach is usage of microoscillatings of a natural genesis that considerably simplifies process of the information deriving and does not require conducting laborious operations with usage of composite devices of man-made seismic wave’s generation.
Proposed in at present Project the approach to the description of relaxational processes conditions essentially differs from a known mode grounded on registrations of gentle earthquakes.
At first at the description of conditions of relaxational processes of environment alongside with strong dynamic appearances the characteristics of impulsive oscillatings with amplitude close to background are attracted, that considerably extends possibilities of a statistical analysis and essentially reduces the requirements to the characteristics of an instrument complex (is admissible to use registering facilities with a low-level dynamic range).
Secondly as determinative magnitudes not absolute parameters of seismic emission considerably time-varying under influence of various natural and local man-made factors are treated but the relative characteristics of rock masses, in which one are reshaped microoscillatings, and also their abnormal deflections from statistically characteristic values.
Thirdly, at an estimation of mechanical stability of environment the characteristics of background microoscillatings (section of a microseismic record with minimum amplitude, statistically representative in a given time interval) are attracted. The latter allows realizing diagnostic of earth crust areas at lack of anomalously high tectonic stresses.