Projefct 1_Comparative study of different storey buildings for Seismic forces

Comparing the different parameters of structure.

ANSWER

Structure – A:

• Open the new model.
• Set the units at Indian parameters.
• Next to prepare the story and Grids formation.
• The grids spacing at 4m in X direction(4 bays) and 4m in Y direction(3 bays).
• To add the material properties of concrete in M30.
• Rebars in HYSD415.
• The beam size is 300mm x 400mm
• The column size is 400mm x 400mm at all stories.
• The slab thickness is 150mm thick.
• This structure is framed by 2 story building and each story height is 3m.
• To add the loads and set the load patterns of dead, live and earthquake(seismic) load.
• The live load is 3 KN/m^2.
• The brickwall infill is 10KN/m.
• Then, to Assign the mass properties, Load combinations, diaphragms, modal analysis.
• After that, to check the model and RUN the analysis.
• Next to get the data of TIME PERIOD and MODE SHAPES at 12 stages.
• For choosing, DISPLAY > show tables.

Structure – B:

• Open the new model.
• Set the units at Indian parameters.
• Next to prepare the story and Grids formation.
• The grids spacing at 4m in X direction(4 bays) and 4m in Y direction(3 bays).
• To add the material properties of concrete in M30.
• Rebars in HYSD415.
• The beam size is 300mm x 400mm
• The column size is 400mm x 400mm at all stories.
• The slab thickness is 150mm thick.
• This structure is framed by 5 story building and each story height is 3m.
• To add the loads and set the load patterns of dead, live and earthquake(seismic) load.
• The live load is 3 KN/m^2.
• The brickwall infill is 10KN/m.
• Then, to Assign the mass properties, Load combinations, diaphragms, modal analysis.
• After that, to check the model and RUN the analysis.
• Next to get the data of TIME PERIOD and MODE SHAPES at 12 stages.
• For choosing, DISPLAY > show tables.

Structure – C:

• Open the new model.
• Set the units at Indian parameters.
• Next to prepare the story and Grids formation.
• The grids spacing at 4m in X direction(4 bays) and 4m in Y direction(3 bays).
• To add the material properties of concrete in M30.
• Rebars in HYSD415.
• The beam size is 300mm x 400mm
• The column size is 550mm x 350mm at all stories.
• The column was oriented along X dierection.
• The slab thickness is 150mm thick.
• This structure is framed by 5 story building and each story height is 3m.
• To add the loads and set the load patterns of dead, live and earthquake(seismic) load.
• The live load is 3 KN/m^2.
• The brickwall infill is 10KN/m.
• Then, to Assign the mass properties, Load combinations, diaphragms, modal analysis.
• After that, to check the model and RUN the analysis.
• Next to get the data of TIME PERIOD and MODE SHAPES at 12 stages.
• For choosing, DISPLAY > show tables.

Structure – D:

• Open the new model.
• Set the units at Indian parameters.
• Next to prepare the story and Grids formation.
• The grids spacing at 4m in X direction(4 bays) and 4m in Y direction(3 bays).
• To add the material properties of concrete in M30.
• Rebars in HYSD415.
• The beam size is 300mm x 400mm
• The column size is 300mm x 550mm at all stories.
• The column was oriented along y dierection.
• The slab thickness is 150mm thick.
• This structure is framed by 5 story building and each story height is 3m.
• To add the loads and set the load patterns of dead, live and earthquake(seismic) load.
• The live load is 3 KN/m^2.
• The brickwall infill is 10KN/m.
• Then, to Assign the mass properties, Load combinations, diaphragms, modal analysis.
• After that, to check the model and RUN the analysis.
• Next to get the data of TIME PERIOD and MODE SHAPES at 12 stages.
• For choosing, DISPLAY > show tables.

Structure – E:

• Open the new model.
• Set the units at Indian parameters.
• Next to prepare the story and Grids formation.
• The grids spacing at 4m in X direction(4 bays) and 4m in Y direction(3 bays).
• To add the material properties of concrete in M30.
• Rebars in HYSD415.
• The beam size is 300mm x 400mm
• The Columns are varying size along building height for

- upper 5 Storeys column size is 400mm x 400mm.

- Bottom 5 storeys column size is 600mm x 600mm.

• The slab thickness is 150mm thick.
• This structure is framed by 10 story building and each story height is 3m.
• To add the loads and set the load patterns of dead, live and earthquake(seismic) load.
• The live load is 3 KN/m^2.
• The brickwall infill is 10KN/m.
• Then, to Assign the mass properties, Load combinations, diaphragms, modal analysis.
• After that, to check the model and RUN the analysis.
• Next to get the data of TIME PERIOD and MODE SHAPES at 12 stages.
• For choosing, DISPLAY > show tables.

Structure – F:

• Open the new model.
• Set the units at Indian parameters.
• Next to prepare the story and Grids formation.
• The grids spacing at 4m in X direction(4 bays) and 4m in Y direction(3 bays).
• To add the material properties of concrete in M30.
• Rebars in HYSD415.
• The beam size is 300mm x 400mm
• The Columns Size is 600mm x 600mm.
• The slab thickness is 150mm thick.
• This structure is framed by 10 story building and each story height is 3m.
• To add the loads and set the load patterns of dead, live and earthquake(seismic) load.
• The live load is 3 KN/m^2.
• The brickwall infill is 10KN/m.
• Then, to Assign the mass properties, Load combinations, diaphragms, modal analysis.
• After that, to check the model and RUN the analysis.
• Next to get the data of TIME PERIOD and MODE SHAPES at 12 stages.
• For choosing, DISPLAY > show tables.

Structure – G:

• Open the new model.
• Set the units at Indian parameters.
• Next to prepare the story and Grids formation.
• The grids spacing at 4m in X direction(4 bays) and 4m in Y direction(3 bays).
• To add the material properties of concrete in M30.
• Rebars in HYSD415.
• The beam size is 300mm x 400mm
• The Columns are varying size along building height for

- upper 5 Storeys column size is 400mm x 400mm.

- Middle 10 storeys column size is 600mm x 600mm

-Bottom 10 storeys column size is 800mm x 800mm.

• The slab thickness is 150mm thick.
• This structure is framed by 25 story building and each story height is 3m.
• To add the loads and set the load patterns of dead, live and earthquake(seismic) load.
• The live load is 3 KN/m^2.
• The brickwall infill is 10KN/m.
• Then, to Assign the mass properties, Load combinations, diaphragms, modal analysis.
• After that, to check the model and RUN the analysis.
• Next to get the data of TIME PERIOD and MODE SHAPES at 12 stages.
• For choosing, DISPLAY > show tables.

Structure – H:

• Open the new model.
• Set the units at Indian parameters.
• Next to prepare the story and Grids formation.
• The grids spacing at 4m in X direction(4 bays) and 4m in Y direction(3 bays).
• To add the material properties of concrete in M30.
• Rebars in HYSD415.
• The beam size is 300mm x 400mm
• The Columns Size is 800mm x 800mm.
• The slab thickness is 150mm thick.
• This structure is framed by 25 story building and each story height is 3m.
• To add the loads and set the load patterns of dead, live and earthquake(seismic) load.
• The live load is 3 KN/m^2.
• The brickwall infill is 10KN/m.
• Then, to Assign the mass properties, Load combinations, diaphragms, modal analysis.
• After that, to check the model and RUN the analysis.
• Next to get the data of TIME PERIOD and MODE SHAPES at 12 stages.
• For choosing, DISPLAY > show tables.

Structure – J:

• Open the new model.
• Set the units at Indian parameters.
• Next to prepare the story and Grids formation.
• The grids spacing at 4m in X direction(4 bays) and 4m in Y direction(3 bays).
• To add the material properties of concrete in M30.
• Rebars in HYSD415.
• The beam size is 300mm x 400mm
• The Columns Size is 800mm x 800mm.
• The slab thickness is 150mm thick.
• This structure is framed by 25 story building and each story height is 3m.
• To add the loads and set the load patterns of dead, live and earthquake(seismic) load.
• The Imposed mass of this building is 10% larger than 3 KN/m^2. (i.e) = 3.3KN/m^2.
• The brickwall infill is 10KN/m.
• Then, to Assign the mass properties, Load combinations, diaphragms, modal analysis.
• After that, to check the model and RUN the analysis.
• Next to get the data of TIME PERIOD and MODE SHAPES at 12 stages.
• For choosing, DISPLAY > show tables.

Structure – K:

• Open the new model.
• Set the units at Indian parameters.
• Next to prepare the story and Grids formation.
• The grids spacing at 4m in X direction(4 bays) and 4m in Y direction(3 bays).
• To add the material properties of concrete in M30.
• Rebars in HYSD415.
• The beam size is 300mm x 400mm
• The Columns Size is 800mm x 800mm.
• The slab thickness is 150mm thick.
• This structure is framed by 25 story building and each story height is 3m.
• To add the loads and set the load patterns of dead, live and earthquake(seismic) load.
• The Imposed mass of this building is 20% larger than 3 KN/m^2. (i.e) = 3.6KN/m^2.
• The brickwall infill is 10KN/m.
• Then, to Assign the mass properties, Load combinations, diaphragms, modal analysis.
• After that, to check the model and RUN the analysis.
• Next to get the data of TIME PERIOD and MODE SHAPES at 12 stages.
• For choosing, DISPLAY > show tables.

Comparison 1

Effect of stiffness on T: compare fundamental natural periods of building E & F as well as G & H . why is there a marginal or significant difference in the fundamental natural periods.

• The natural period of E is 2.91s
• The natural period of F is 2.66s
• The natural period of G is 3.86s
• The natural period of H is 3.906s
• Comparing a building of E,F,G & H are having a different natural period of occur due to depending upon lateral forces action.
• Because of the building E & F are 10 story with a different size of column fixation and more vary the story column size.
• The same for building G & H are 25 story with a different column sizes with different stories.
• Therefore , the structure having gradually increases the load, so the stiffness of this building becomes changing.
• Since, here considering for variation of reduced the moment of inertia, the overall stiffness of the structure will reduce.
• Due to reduced stiffness about structure similarly the structure could relatively flexible and hence would attracting the lower seismic forces.

Comparison 2

Effect of mass on T : compare fundamental natural periods of building H, J & K. Have the building becomes more flexible or stiff due to change in mass

• The natural period of H is 5.48s
• The natural period of J is 5.47s
• The natural period of K is 5.499s
• The fundamental natural period of building is slightly varying, because of addition of imposed load 10% more than H in J Building and 20% more than H in K Building.
• But , this factor varying is minor to comparing other compoents.
• The mass of structure have increased, it extend to extra deformation in response to an lateral forces, so structure have more flexible an object , obviously the stiffness is less in it.

Comparison 3

Effect of building height on T: How does the fundamental natural periods of buildigs A,B,F and H change with change in building.

• The natural period of A is 0.60s
• The natural period of B is 1.25s
• The natural period of F is 2.66s
• The natural period of H is 3.90s
• The building of A is 2 story, B is 5 story, F is 10 story and H is 25 story.
• The building height is varying , same varying the cross-wing forces.
• Therefore, the high rise building will affect the thermal expansion and wind forces across the srcture, so the structure need more efficient framed model to prevent from win load action.

Comparison 4

Effect of column orientation on T: How does the fundamental natural periods of buildigs B,C & D change with change in column orientation.

• The natural period of B is 1.25s
• The natural period of C is 1.34s
• The natural period of D is 1.30s
• For this comparision , the story height are same ( 5 stories), but the column orientation get varied from one another like B is 400mm x 400mm for same orientation in both direction, C is 550mm x 300mm for orientation along X direction and D is 300mm x 550mm along Y direction.
• Therefore, the framed section
• are varying from one another, may it have occur some variation of natural period during the seismic loads action.

Comparison 5

Effects of flexural stiffness of structural elements on Mode shapes: compare fundamental natural periods of building B in two situation when flexural stiffness of beams relative to that of adjoining columns is very small versus when it is large.

• The natural period of B in T1 is 1.25s ( MODE 1 )
• The natural period of B in T2 is 1.087s ( MODE 2 )
• The column rigidity is more higher with fixed supports. The higher is more effectiveness for flexural stiffness.

Comparison 6

Effects of Axial stiffness of vertical members on mode shapes: compare fundamental natural periods of building H in two situation when Axial cross-sectional area of columns is very small Versus When it is Large.

• The natural period of H in T1 is 5.71s ( MODE 1 )
• The natural period of H in T2 is 5.41s ( MODE 2 )
• To compare the mode shape of natural period of higher is better axial stiffness to resist of witstanding of structure to formation of deflection at members.

Comparision 7

Effect of degree of fixity at column base on mode shape : compare fundamental natural periods of building B in two situation when base of column is pinned versus when it is fixed.

• The natural period of B in T1 is 1.25s ( MODE 1 )
• The natural period of B in T2 is 1.087s ( MODE 2 )
• The rotational stiffness at the base of a column affects the force and displacements demands on frame elements during an earthquake.
• In most analysis conducted for design, the column base is considered to be fully fixed.
• They showed that pinned to fully fixed column base cases bounded the responses for all frames.