Conceptual design of a building with columns and shear walls

1

Lets see all the criteria,observations and the final conclusions of the building

Restrain of floor shrinkage

A- Its is of full restrains at all the corners

B- Corners are left and restrains are along the edges

C- The restrains are non uniform

We can conclude that A has high restrain so can have cracks , B has an average restrain and cracks as well while C has not effectively restrain

The lateral stiffness

A- Since the restrains are at the corners it has less lateral stiffness in X and Y direction

B- The stifness is higher and uniform

C - It has non uniform stiffness

We can conclude that B has higher stiffness in X and Y compared to other

Torsion with respect to vertical axis

A- Corner walls provide more resistance to twist

B - Its also have good resistance to twist

C - Here irregular walls present sa poor resistance to twist

A is the best option for torsion and C is the worst one

Vertical reinforcement for similar base capacity

A- Wall are subjected to nominal flexural moment and heavy twisting moment

B- It has nominal twisting moment

C- It has heavy flexural and twisting moment

C requires more vertical reinforcement and B needs least

Static eccentricity

A- It structurally symmetric

B - It is also structurally symmetric

C- It is Un symmetric

C will have static eccentricity which is important

Systems redundancy

A- Load supports are uniformly placed in both the direction

B- Load supports are uniformly placed in both the direction

C- Concetrated lateral load supports in both the axis

A and B has more redundant than C

Foundation system

A - Because of L shaped walls geometry and design of foundation is critical

B- Walls are in line and easier to fix the geometry and design of foundation

C- They are also east to fix in geometry and design as well but critical in the design aspect

B and C has isolated or straped footing while A need box foundation because it has L shaped walls

Architectural constraints

A- Wall obstruct only at the corners

B - Here walls obstruct at the faces

C- One side of the vertical wall does not allow passage

In the architectural point of view A is preferably choosed and B should under discussion and C is not accepted

2

Indirect lateral load transfer in X and Y directions

The beams are connected to other beams which in ineffective during the lateral loading because the loads travell directly to one beam and primary beam occurs the shear failure

Eccentricity

The longer the distance between centre of mass and centre of sstiffness the higher torsional moment

The plan is subjected to higher torsional moment

Strong beam weak coloumn possibility

The coloumn sizes as shown as 20x25 and beam is of depth 50cm

The inertia of beam is greater than the coloumn

If the coloumn has adequate reinforcement it is Ok but reinforcemet detail is not given since it is doubtful

Propose plan

3

Observations

Floor plan - The given plan is not symmetric and uniform

So the lateral force definately effects the building so the lateral resisting force and torsional accomodating should be given

Random internal coloumn-

The coloumns are placed randomly so they cannot transfer the loads efficiently

we have to assume and design those coloumns for only gravity loads

Floor to floor variations in partition walls and beams

Partition walls provide an important mass controll in a building and beam play key role in shear transfer from floor to beam

So heavy ditortion and distribution of lateral loads will happen

Suggestion on the lateral load syatem and its foundation

Torsional forces should be controlled by adding corner shear wall

The proportionan of left floor area is greater than right so heavier shear wall should be provided at left side

Corner shear wall should be on the box foundation and connected by link beams

The internam coloumns shall be supported by isolated footing. and connected with shear walls through tie beams

Proposed plan