For More Functional and Structural Safety – Seismic Design of Plant Parts and Components
Earthquake-resistant Construction
Earthquake Verification According to International Standards
Planners and operators of plants, machines and structures are at minimum responsible for their stability, which can become a challenge in seismically active areas.
Different locations require different standard-compliant earthquake design of buildings, plants, machinery, components and infrastructure. The focus is, of course, primarily on the safety of employees and residents, but our solutions also aim to protect the investment and maintain operational capability.
Earthquakes themselves generally pose much less immediate danger to people than many people think. Rather, the problem is buildings, machines, plants and infrastructures that are not (structurally) safe or lose their integrity or functionality, thus putting human lives at risk and leading to high costs. The good news: By applying and adhering to standards and guidelines, the risks are minimized to an acceptable level – both in the context of new construction and new design of plants and components, as well as during recalculation and retrofitting. The protection of persons or the safety of a plant can be additionally increased with a targeted integration of a monitoring system for the detection of earthquakes.
Whether German, European or international regulations (DIN EN 1998, IBC, UBC, KTA, IEEE, IEC, etc.) – Our know-how covers earthquake standards worldwide
In order to be able to offer high quality earthquake engineering for our customers with projects all over the world, we intensively and continuously deal with earthquake standards worldwide. To name a few project examples:
Control cabinet in Chile (NCh2369)
Brewery boiler in California (ASCE 7)
Packaging facility in Australia (AS 1170)
Nuclear interim storage facility in Germany (KTA 2201)
Data center in Turkey (DBYBHY 2007)
Substation in the USA (IEEE 693)
Switch cabinet in China (IEEE 344)
Earthquake Verification and Seismic Design
Development and implementation of a verification concept:
– Plant structures (e.g. power plants, chemical plants, production plants, switchgears)
– Plant parts, components and their anchorages
Verification calculation with (quasi-)static equivalent methods, spectra methods (RSMA), linear or non-linear time history calculations or probabilistic methods
Planning, specification, implementation and evaluation of earthquake tests by vibration testing
Similarity considerations by using existing earthquake proofs
Determination of the soil-structure interaction by means of special simulation programs, e.g. for the determination of response spectra
Assessment and Retrofitting
Assessment of earthquake damage, incl. classification of damage patterns
Seismic re-evaluation of existing buildings, plants, machines or components by inspection, calculation or measurement
Elaboration of proposals for the retrofitting and upgrading of existing buildings, machinery and equipment
Communication
Preparation of auditable and quality-assured documentation of all work and results in accordance with national and international requirements
Preliminary review and quality assurance of third-party design documents for the operator
Support in technical discussions with contractors, assessors and authorities
Representation vis-à-vis inspectors and authorities
Earthquake Resistant Construction
Earthquake design and earthquake measurement of structural systems.
Earthquakes don’t kill people, buildings do.
One of the greatest dangers during an earthquake are collapsing buildings. This is precisely why many countries now have numerous standards and guidelines that make earthquake-resistant or earthquake-compliant construction mandatory – to protect people, to minimize damage and to limit any consequential damage.
From an adaptation of the floor plan to basic insulation to active or passive vibration mitigation using absorbers and dampers: There are numerous concepts to make large and small structures earthquake-resistant in the event of an emergency and to avoid failure of the supporting structure. At Wölfel, we have been dealing with this issue for decades and will provide you with advice on all aspects of earthquake-resistant and earthquake-compliant construction – both for new buildings and for recalculation and retrofitting.
Shaking Table Test of a Two-Storey Lightweight Steel Structure (Research project ELISSA)
Services we offer:
Preparation and review of specifications on the subject of earthquakes
Design of structures made of reinforced concrete, steel and masonry for the load case earthquake according to European and international standards such as DIN EN 1998-1 and ASCE 7
Verification of the load-bearing capacity and serviceability of structures and components made of reinforced concrete, pre-stressed concrete, steel and masonry
Analyses by means of static or dynamic calculation methods as well as time history calculations
Design of earthquake protection systems such as seismic isolation, dampers or absorbers
Design of Plant Parts
Standard-compliant earthquake qualification of plant parts and mechanical as well as electrical components – Earthquake verification through earthquake simulation
Depending on the product and its classification, and on the (country-specific) regulations, at a minimum the stability of the anchorage of a component under seismic action must be verified. Further requirements may extend to integrity (leak tightness) and functionality (especially for electrical components) during and after the earthquake event.
Which method is used for verification is determined by numerous factors. Depending on the regulations and requirements, the proof of functionality can be provided, for example numerically using an FE model (earthquake calculation) and/or experimentally by means of a vibration test, as is often required. In the following overview you will find our range of services for mechanical and electrical components – we provide you with advice to develop the optimal verification concept for your specific application in close cooperation.
Mechanical Component
Which mechanical components (e.g., piping, tanks, coolers, LNG-, hydrogen tanks/lines) must be considered as part of the earthquake design depends, in particular, on the overall protection goal for the machine or plant.
Depending on the requirements, the verification can be done by calculation (quasi-static equivalent method, response spectrum method, time history method), experimental methods (earthquake test) and/or alternative methods (similarity, plausibility). Internationally, the ASCE/SEI 7 set of rules is frequently used for mechanical components; for detailed verifications, there are additional component-specific sets of rules.
Services we offer:
Consulting for the determination of input data, the adaptation of designs as well as for the development of a verification concept
Consulting with regard to internationally recognized standards
Design of components for the load case earthquake
Support in the introduction of a uniform procedure for you and your suppliers
Support in clarifying customer questions on the subject of earthquakes and in representing you vis-à-vis authorities and TÜV testing bodies
The use of electrical components (e.g. switch cabinets, electric motors, generators, transformers, gas-insulated switchgear (GIS), gas-insulated piping, valves, pumps, …) may be subject to compliance with country-specific earthquake requirements, both at home and abroad. If this is the case, the seismic safety of the respective components has to be verified according to the local regulations.
Services we offer:
Advice on the determination of earthquake input data
Verification by calculation (usually FE calculation: linear/non-linear, quasi-static/dynamic with time-history method or RSMA calculation)
Verification by vibration test (uni- or multi-axial, electric or hydraulic vibration table)
Test planning, test specification, test monitoring, test evaluation
If the boundary conditions allow it: Verification by plausibility/similarity considerations (lowest time and cost expenditure)
Advice on design optimization
Representation vis-à-vis inspectors and authorities
Creation of customized software for processing/analysis of (earthquake) signals: Time histories, response spectra
We consider project-specific requirements resulting from (inter)national conventional and nuclear regulations and earthquake specifications:
KTA 2201.4 – Design of NPPs against Seismic Events, Part 4: Plant Components
RCC-E – Design and Construction Rules for Electrical Equipment of Nuclear Islands
IEEE 344 – IEEE Standard for Seismic Qualification of Equipment for Nuclear Power Generating Stations
IEC 68-3-3 – Environmental testing – Seismic test methods for equipment, guidance document
IEC 980 – Recommended practices for seismic qualification of electrical equipment of the safety system for nuclear generating stations
IEC 61225:2020-11 – NPP – Instrumentation, control and electrical power systems – Requirements for static uninterruptible DC and AC power supply systems
IEEE 693 – IEEE Recommended Practice for Seismic Design of Substations
IEC 62271-207 High-voltage switchgear and control gear – Part 207: Seismic qualification for gas-insulated switchgear assemblies for rated voltages above 52 kV
IEC 62271-210 High-voltage switchgear and control gear – Part 210: Seismic qualification for metal enclosed and solid-insulation enclosed switchgear and control gear assemblies for rated voltages above 1 kV and up to and including 52 kV
ASCE 7 – Minimum Design Loads for Buildings and Other Structures
ICC-ES AC 156 – Acceptance Criteria for seismic certification by shake-table testing of non-structural components
DIN EN 1998 (EC 8) – Design of structures against earthquakes, part 1-6.
Seismic Instrumentation
Seismic Instrumentation and Seismic Switch – Permanent protection of your plant through earthquake monitoring
If an earthquake hits an industrial facility, a building, a power plant or other infrastructure, it can immediately and reliably be detected by installing seismic instrumentation. This opens up the possibility of initiating protective measures very quickly. If certain limit or design values (e.g. response spectrum) are exceeded, alarms are automatically triggered or entire plant sections are automatically shut down. This reduces or even prevents the occurrence of secondary damage such as explosion, fire and release of substances as well as their consequences. Our portfolio ranges from the so-called “seismic switch” for monitoring buildings or for shutting down machinery and equipment to certified systems, e.g. for monitoring power plants. We use equipment technology from the renowned Swiss manufacturer SYSCOM.
