Modelling influence of paraseismic tremors on precast apartment buildings COSTC26 Conference: Urban Habitat Constructions under Catastrophic Events Jacek Barański, Piotr Berkowski, Grzegorz Dmochowski, Faculty of Civil Engineering Wrocław University of Technology Poland
COSTC26 Conference: Urban Habitat Constructions under Catastrophic Modelling influence of paraseismic tremors Events on precast apartment buildings Presentation plan Introduction Description of selected types of precast buildings FEM static and dynamic modelling Model of dynamic calculations Final remarks
COSTC26 Conference: Urban Habitat Constructions under Catastrophic Modelling influence of paraseismic tremors Events on precast apartment buildings I Phenomena that occur in copper mining areas in Poland n are as follows: t r abasement of terrain, slope of terrain, and creep of o d soil surface u they have no decisive influence on the technical condition of c buildings and structures t i ground vibrations caused by mining tremors, o n generally described using velocity and acceleration of soil vibrations they cause cracks in structural elements or at the contact surfaces between different structural elements or materials
COSTC26 Conference: Urban Habitat Constructions under Catastrophic Modelling influence of paraseismic tremors Events on precast apartment buildings T WWP (Wrocław large plate) building system: y p • typical height of 5 or 11 storeys e s • foundations are made in the form of concrete continuous footing or foundation plate o • basement walls are made as monolithic ones f • internal transversal bearing walls are 14 cm thick b • vertical edges are finished with the so-called “locks” with u reinforcing steel bars left, both elements made with aim to i create vertical cores filled with concrete during assembly l • horizontal edges are provided with two steel bolts, helping d i to stabilize and mount higher storey walls; filled with cement n mortar g s
COSTC26 Conference: Urban Habitat Constructions under Catastrophic Modelling influence of paraseismic tremors Events on precast apartment buildings T WWP building system: y p • gable walls are designed as three-layer ones with total e s thickness of 21 cm and with reinforced 12 cm thick concrete bearing layer o • curtain walls, also the three-layer ones, are precast ones f with a thickness of 16 cm, with reinforced concrete bearing b layer 5 cm thick u • floor slabs are 14 or 16 cm thick; typical floor span (load- i bearing wall spacing) was 2.4, 3.0, 4.8 and 5.4 m l • plates are reinforced in one direction, as being based on d i the vertical walls on the opposite ends only. n g s
COSTC26 Conference: Urban Habitat Constructions under Catastrophic Modelling influence of paraseismic tremors Events on precast apartment buildings T WWP building system: y p e s o STRENGTHENED LONGITUDINAL WALLS f b u i l d Horizontal plan of WWP building with strengthening i n g s
COSTC26 Conference: Urban Habitat Constructions under Catastrophic Modelling influence of paraseismic tremors Events on precast apartment buildings T WBL (Wrocław block) building system: y p • transversal load-bearing wall system is used e s • floor slabs are based on the external gable and internal bearing walls o • height of these buildings is up to 8 or 10 storeys f • underground storeys are constructed from precast b elements or made as monolithic ones u • walls are made of full or hollow precast blocks i • ground floor concrete walls are 24 cm thick with l d longitudinal circle channels i • floor slabs are also hollow ones with 24 cm of thickness; n plates are canted on the ends what allowed the realization of g ring beam s
COSTC26 Conference: Urban Habitat Constructions under Catastrophic Modelling influence of paraseismic tremors Events on precast apartment buildings T WBL (Wrocław block) building system: y p e s o f Horizontal plan of WBL building b u i l d i n g s
COSTC26 Conference: Urban Habitat Constructions under Catastrophic Modelling influence of paraseismic tremors Events on precast apartment buildings S FEM WWP 2D & 3D building model: t a model was prepared in two stages, using the standard t i LUSAS program elements: c & in the first stage 2D model of the 11-storey building was d y created: n a in place of all the structural horizontal joints 2D elastic m elements " joint2D ” were introduced i c bearing lateral walls system of the building was replaced F by beam elements with equivalent geometric characteristics E M
COSTC26 Conference: Urban Habitat Constructions under Catastrophic Modelling influence of paraseismic tremors Events on precast apartment buildings S FEM WWP 2D & 3D building model: t a system was tested for dead and wind loads and uneven t i settlement in the longitudinal direction of the building c & during the calculation static system of structure was d changed by changing stiffness of “ joint2D ” elements y n a influence of curtain walls and technological service loads m were not taken into account i c F E M
COSTC26 Conference: Urban Habitat Constructions under Catastrophic Modelling influence of paraseismic tremors Events on precast apartment buildings S FEM WWP 2D & 3D building model: t a the second model was a fully 3D model of a building t i constructed in the WWP system c & d y n 3D FEM model a of precast m WWP building i c F E M
COSTC26 Conference: Urban Habitat Constructions under Catastrophic Modelling influence of paraseismic tremors Events on precast apartment buildings S FEM WWP 2D & 3D building model: t a bearing carrying system was modeled with help of rigid t i floor slabs and load bearing vertical walls based on them in c transversal direction & d in y the longitudinal direction sections of walls along n stairways were also the bearing elements a m support of building was modeled as the fixed one in all of i c the examples F E M
COSTC26 Conference: Urban Habitat Constructions under Catastrophic Modelling influence of paraseismic tremors Events on precast apartment buildings S FEM WWP 2D & 3D building model: t a in the model the walls were not connected to the floor slabs t i directly, but by using elements of " joint3D ", analogous to c " joint2D ”, but working in the spatial layout. Using them & horizontal joints in three dimensional space were modeled. d y n examples of calculations under action of wind, uneven a settlement and paraseismic tremors were realized m i c F E M
COSTC26 Conference: Urban Habitat Constructions under Catastrophic Modelling influence of paraseismic tremors Events on precast apartment buildings S FEM WWP primary joint model: t a primary joint model was geometrically identical with the t i typical horizontal joint used in precast WWP building system c & d y n a m i c F E M
COSTC26 Conference: Urban Habitat Constructions under Catastrophic Modelling influence of paraseismic tremors Events on precast apartment buildings S FEM WWP primary joint t model: a t i 3D elements c with 8 nodes & were applied d y as finite elements n a Primary model – m results of x – i stresses beginning phase. c F E M
COSTC26 Conference: Urban Habitat Constructions under Catastrophic Modelling influence of paraseismic tremors Events on precast apartment buildings S FEM WWP primary joint t model: a t i nonlinear analysis was c carried out using built-in & LUSAS FEM System d y multi-crack concrete n Jefferson model a m Primary model – results of i x – stresses c failure phase F E Failure mechanism starts in the middle of the joint M
COSTC26 Conference: Urban Habitat Constructions under Catastrophic Modelling influence of paraseismic tremors Events on precast apartment buildings S FEM WWP substitute t joint model: a t i primary model ocurred c useless for large models & analysis because of d y complicated form n a substitute model was m built with LUSAS finite i element called “ joint ” c LUSAS FEM substitute containing translational model of joint between F and rotational springs precast elements E M
COSTC26 Conference: Urban Habitat Constructions under Catastrophic Modelling influence of paraseismic tremors Events on precast apartment buildings S FEM WWP substitute t joint model: a t i “ joint ” characteristics, c as spring stiffness, & were calculated d y according to the primary model n a element was suitable for m static and dynamic analysis i c when was applied to substitute FEM model of whole horizontal joint part of the horizontal joint F E M
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