Conceptual design of a building with columns and shear walls

1):

Aim: Compare the three alternatives, taking into account restraint of floor shrinkage, lateral stiffness torsional one with respect to the vertical axis, vertical reinforcement similar base capacity static eccentricity, system’s redundancy, foundation systems, architectural constraints etc. from the given building plan.

Plan A Plan B Plan C

Criteria:

1.

Restraint of floor shrinkage

Observation

Full restraint at all conners

Conners are left free but restraint at edge

Non uniform restraint

Conclusion

Plan (a) have higher restraint to shrinkage. Thus lead to crack in the floor. Plan(b) is average. Plan(c) will not effectively restraint to shrinkage. So possible less crack

2.

Lateral stiffness

Observation

Comparatively lower lateral stiffness in both x and y

Uniformly and comparatively higher lateral stiffness in both x and y

Non uniform lateral stiffness in both x and y

Conclusion

Plan (B) will provide higher lateral stiffness for a pure seismic acceleration in x and y direction

3.

Torsion with respect to vertical axis

Observation

Conner wall provide more resistance to twist

Edge wall provide good resistance to twist

Irregular wall provide poor resistance to twist

Conclusion

Plan(A) be the best option with respect to torsion where plan(C) is the worst one

4.

Vertical reinforcement for similar base capacity

Observation

Walls are subjected to nominal flexure moment and heavy twisting moment

Walls are subjected to nominal twisting moment

Walls are subjected to heavy flexure moment and twisting moment

Conclusion

Plan c will require higher reinforcement and plan b require less.

5.

Static eccentricity

Observation

Structurally symmetric

Structurally symmetric

Un-Structurally symmetric

Conclusion

Only plan c will have Static eccentricity and its significant

6.

Systems redundancy

Observation

Uniform placement of lateral load support in both the axes

Uniform placement of lateral load support in both the axes

Concentrated lateral load support in both the axes

Conclusion

Plan a and b are more redundant then plan c

7.

Foundation system

Observation

Due L shape wall the geometry of foundation and its design will be critical

Wall are in line easy to fix the geometry and design of foundation

Walls are in line and concentrated. Easy to fix the geometry of foundation but critical in design

Conclusion

plan b and c shall be incorporated with isolated footing/strip footing plan a is recommended to have peripheral box foundation

8.

Architectural constraints

Observation

Walls obstruct only corner

Wall obstruct the face of the building

Vertical wall will not allow the passage

Conclusion

Architecturally speaking plan a id the preferred plan b is subjected to discusses plan will not be accepted for both architecturally and commercially

2):

Aim: To observe the given structural plan in terms of seismic influence and to suggest the better alternative.

Procedure:

Issue in given farming plan:

Indirect lateral load transfer in x and y direction: The are connecting to another beam which is ineffective during later load transfer in such condition the primary beam is prone to shear failure

Eccentricity: The longer the distance between the center of the mass and center of the stiffness the higher torsional moment of the building as per the given plan eccentricity the building is subjected to higher torsional moment in both x and y direction

Strong beam week column: The size of the column majorly mentioned as 25cm x 25cm but all the beams have much deeper section 50cm inertia of the beam is visually higher then column is the column reinforcement is adequately grater then the beam its okey but we do not have reinforcement details so it recommend to have slight bigger in size of the column

Alternate scheme:

3):

Observation in the given farming plan:

Floor plan: The floor plan building is not either uniform or symmetric. So naturally any lateral load include in the floor plan is not have 100% influence in the same direction. Definitely a special lateral load resisting system for these torsional moments should be accommodated

Random internal column: Since the internal column are random they are unable to transfer lateral load efficiently and can not be achieve desirable building response. So we have to assume and design those column for only gravity load.

Floor to floor variation is partition wall and beams: partition wall provide an important mass control in the building and play the key role in the shear transfer to floor to beam. All this elements are not in order so heavy distortion and distribution of lateral load will happen.

Suggestion on the lateral load system & its foundation:

• Heavy torsional force should be control by respective lateral load system. So “corner shear wall “ are suggested.
• The proportion of floor area is greater then the left side of the then the right side. So the conner shear wall should be heaver then the right
• Conner shear wall shall be preferably supported over box foundation shear wall should be connect by link beams to transfer the shear from one to other.
• The internal column shall be supported by isolated footing. Those isolated footing can be connect with the shear wall through the tie beam.