Conceptual design of a building with columns and shear walls
1A)
CASE A)
Restraint of floor shrinkage
obesrvation full restraint at all corner
conclusion option a will have higher restraint to shrinkage thus lead to crack in the floor, option B is average option C will not effectively restraint the srinkage so possibly less cracks
The lateral stiffness
obesrvation comparatively lower lateral stiffness in both X and Y
conclusion option b will provide higher lateral stiffness for a pure seismic acceleration X and Y direction
Torsion with respective vertical axis
observation Corners walls provide more resistance to twist
coclusion option a will be the best option respect to torsional resistance wheras option c is the wrost one
Vertical reinforcement for similar base capacity
observation walls are subjected to nominal flexural moment and heavy twisting moment
conclusion only c will required heigher vertical reinforcement and option b will required least
static eccentricity
observation structurally symmetric
conclusion only option C have static eccentricity and it is significant
system redundancy
obseravation uniform placement of lateral load support in both the axes
conclusion option a and b are more retundant than c
foundation system
observation Due to L shaped wall the geometry of foundation and its design will be critical
conclusion option B and C will be incorporated with isolated/strip footing option a is recommended to have peripheral box foundation
Architectural constraints
observation walls obstruct only corners
conclusion Architecturally speaking option a the preffered one option b is subjected to discussion option c will not be accepted both architecturally and commercially
CASE B)
Restraint of floor shrinkage
obesrvation corners are left free but restrain along the edge
conclusion option a will have higher restraint to shrinkage thus lead to crack in the floor, option B is average option C will not effectively restraint the srinkage so possibly less cracks
The lateral stiffness
obesrvation comparatively higher lateral stiffness in both X and Y
conclusion option b will provide higher lateral stiffness for a pure seismic acceleration X and Y direction
Torsion with respective vertical axis
observation edge walls provide good resistance to twist
coclusion option a will be the best option respect to torsional resistance wheras option c is the wrost one
Vertical reinforcement for similar base capacity
observation walls are subjected to nominal twisting moment
conclusion only c will required heigher vertical reinforcement and option b will required least
static eccentricity
observation structurally symmetric
conclusion only option C have static eccentricity and it is significant
system redundancy
obseravation uniform placement of lateral load support in both the axes
conclusion option a and b are more retundant than c
foundation system
observation walls are in line easy to fix the geomentry and design of foundation
conclusion option B and C will be incorporated with isolated/strip footing option a is recommended to have peripheral box foundation
Architectural constraints
observation walls obstruct the faces of building
conclusion Architecturally speaking option a the preffered one option b is subjected to discussion option c will not be accepted both architecturally and commercially
CASE C)
Restraint of floor shrinkage
obesrvation non uniform restraints
conclusion option a will have higher restraint to shrinkage thus lead to crack in the floor, option B is average option C will not effectively restraint the srinkage so possibly less cracks
The lateral stiffness
obesrvation non uniform lateral stiffness in both X and Y
conclusion option b will provide higher lateral stiffness for a pure seismic acceleration X and Y direction
Torsion with respective vertical axis
observation irregular walls are provide very poor resistance to twist
coclusion option a will be the best option respect to torsional resistance wheras option c is the wrost one
Vertical reinforcement for similar base capacity
observation walls are subjected to nominal flexural moment and twisting moment
conclusion only c will required heigher vertical reinforcement and option b will required least
static eccentricity
observation structurally un-symmetric
conclusion only option C have static eccentricity and it is significant
system redundancy
obseravation concentrated lateral load support in both the axes
conclusion option a and b are more retundant than c
foundation system
observation walls are in line & concentrated easy ton fix the geomentry of foundation but critical in design
conclusion option B and C will be incorporated with isolated/strip footing option a is recommended to have peripheral box foundation
Architectural constraints
observation vertical wall will not allow passage
conclusion Architecturally speaking option a the preffered one option b is subjected to discussion option c will not be accepted both architecturally and commercially
2A)
There is a two way eccentricity in the frame along X direction and Y direction also with stiffness the eccentricity in X direction is larger when compared to Y direction.
There is only two continuous frames in the structure that is B1 and B2 in the X direction and B9, B10 and B11,B12 in the Y direction and all other beams are broken at the midway in the frame.
There will be Torsional flexibility in the structure.To avoid torsional restraints it is better to make the room dimensions even in both X and Y direction and placing the columns at the junction of two wall if it is feasible better to provide shear wall at appropriate location.
The fundamental translation mode of vibration is larger than the fundamental torsional mode of vibration.
3A)
observation in the given framing plan
Floor plan:
the floor plan of the building is not either uniform or symmetric so naturally any lateral load induced in the floor will not have 100% influence in same direction definately a special lateral load resisting system for these tortional moment should be accommodated
Random internal column:
since the internal column are random they are unable to transfer lateral load effectively and can not achieve desire building responce so we have to assume and design those columns for only gravity load
Floor to floor variations in partition walls and beams
partition wall provide an importance mass control in a building plan key role in shear transfer from floor to beam all these elements are not in order so heavy distortion and distribution of lateral loads will happen
Suggestion on the lateral load system and its foundation:
heavy tortional forces should be contrrolled by respective lateral load system so corner shear walls are suggested
the propotion of floor area is greater on ther left side than the right side so corners shear walls on left side should be havier than the right
corner shear wall shall preferably be supported over a box foundation shear walls should be connected by link beam to transfer shear from one to the other
The internal columns shall be supported by isolated footing those isolated footing can be connected with shear walls through tie beam