HILASE - New Laser for Industry and Research -Prague:

2013

Description The main objective of the presented project „HILASE“ is to develop laser technology with breakthrough technical parameters. Laser Centre „HILASE“ with these parameters will be unique not only in the Czech Republic, but also in Europe.
„HILASE“ object is divided into two parts, two laser-storey building hall and three-storey office section. The  measures of the laser hall is 25.9 x49,9m, object height is 8.90 m. The ceiling above 1. st floor (the laser hall) and roof above 2. nd floor have a  common beam formed in the 2. nd floor. The beam is broken by a number of large holes for wiring technology lasers. The beam has a span of 25.9 meters and was designed as monolithic reinforced.The Administartive building measures 14.7 x 60.0 meters and a height of 11.85m.  The structure is designed as a monolithic skeleton, edge parts of the building are in 2.nd and 3.rd storey cantilereved.
Foundation of the building is designed on piles. The foundation of  laser plate,  located in the 1. st floor of the hall is, is designed of 420 mm thickness. The  dynamic filter is designed under the laser plate, in  order to reduce transmission of vibrations from the subsoil into the building. Conceptual design and structrual analysisThe building was designed according to the strict technological requirements for the operation of the laser. Especially very strict are the limits for the dynamic behavior of laser foundation slabs from subsoil vibration. This vibrations propagates from subsoil enviroment  to the building structure. The first natural frequency of the laser slabs must be greater than 25Hz. Limit deflection of any point structure is <Δuz,rqr = 0.2 micron in the 5-50Hz, and max Δuz,rqr = 0.02 micron in the 50-100Hz. These values ​​are very stringent and difficult to achieve in the design of the foundations slabs. The foundation plate is located in the hall of the building. The foundation plate is done in bad geological layers. To reduce vibrations transer from subsoil to the foundation structure, the dynamic filter was designed, at the boundary of  both system.  The leyered structure is composed with a high and very low bulk density and also a high and low speed  of vibratinon through this strata. Filter efficiency was determined value of 30%. Own response to dynamic exciting (loading) was performed using spectral analysis computing system by SCIA ENGINEER 2010 to the 3D model. Control calculations were carried out in the reference software. The foundations laser plate was modeled as 3D (wall-plate) structure supported by a flexible "Winkler - Pasternak subsoil" (supporting the corners and edges were modeled according to the "effective model Kolář-Němec" -  to reflect the impact of the edge surrounding soil).  The values ​​of soil were modeled using envelopes subsoil with the fact, that the control-verify was made by system SOILIN. Vibration load was considered 0.00008 m/s2 and was an expert estimate of experiences from other sites and vibration measurements in the locality.
The ceiling above 1. st floor (the laser hall) and roof above 2. nd floor have a  common beam formed in the 2. nd floor. The beam is broken by a number of large holes for wiring technology lasers. The beam has a span of 25.9 meters and was designed as reinforced. For global analysis several nonlinear 2D and 3D models were created in SCIA ENGINEER 2010. Controlling calculation was performed on the beam element. Crucial to the design of reinforcement was “strut and tie” model, which served for the design and control of global reinforcement and reinforcement around the holes. This method confirmed good agreement with nonlinear calculation by SCIA ENGINEER.Conclusion The design of laser hall, in particular the foundation of the laser plate requires to link together deep expertise in geotechnical and dynamic of structures. Calculations of structures exposed to subsoil  enviroment vibrations are very complicad and requieres high theoretical and practical experience. In this case, to achieve very strict  limits dynamics respons of the foundations plate, the dynamic filter was used, at the boundary both systém, to reduce the transmission of vibrations from the ground to construction. Checking of calculations of the trusses was perfomed by „strut – and tie“ method. This method confirmed good agreement with nonlinear calculation by SCIA ENGINEER. 

HILASE CONTEST (PDF)