Concept on positioning of Columns

1)

Based on the investigation of the framing plan with respect to symmetry in x axis direction

if we split the plan is vetically half. it will look mirrored, so we conclude the given plan is symmetrical in x direction.

Based on the investigation of the framing plan with respect to symmetry in Y axis direction

if we split the plan is vetically half. it will look mirrored, so we conclude the given plan is symmetrical in x direction.

REDUNDANCY

Based on the investigation of the framing plan with respect to redundancy in x axis direction

the column in x direction are comparetively more and evenly spaced so the structure is more redudant in x direction. except the top and bottom column row are having quite longer spans.

Based on the investigation of the framing plan with respect to redundancy in y axis direction

The column in y direction are comparitively lesser but evelny spaced so the structure is redundant but lesser than that of in x direction.

BI- DIRECTIONAL STIFFNESS

The column in horizontal direction are connected with straight to staright beams. this means, any lateral load(seismic forec in x direction) passing form left end of the buidling will have its apth straight till it reaches right end of the building. so no or less possibility of force diversion takes place.

The column in vertical direction are connected with straight to straight beams. so lateral load passing from south side of the building will get divertyed to east to west direction to reach the next bay. there will be majore force diversion take place with seismic force in y direction. the framing plan is weak with respect ton bi directional stiffness in y direction.

DUCTILITY

Based on the investigation of the framing plan with respect to ductility.

prima facie. the aspect ratio of the plan clearly hints are column in x direction compatred to y- direction. it will result in higher stiffness of the building in x direction, which would reduce ductility in x axis.

moreover, the x force will easily pass from one bay to its next due to beam alignment. whereas, the y-force will struggle to pass through. The north-south beams are arranged in zigzag which leads to a dicontinuous bracing south beam are arranged in zigzag which leads to a discontinous bracing

We conclude that the given framing plan i smore ductile in y direction than that of in x direction.

2)

VERTICAL IRREGULARITY - The building plan is large bottom stories. the floor plan areas are getting reduced with increase in height. these building offsets to be crosschecked with refrence to is-1893-2016 table-6 serila number(iii).

SOFT STOREY- the buildinng has uncovered opening space in 6th floor . as there is no occupancy or a partiion wall. this will lead ton plastic hinge formation at the columns(with reference to IS*1893-2016 figure 4A). This has to be checked and suffciently designed.

SLOPY BASE - The building is constructed on a sloping ground at one side. this will lead to significant variation in th stiffness (with refrence to IS-1893-52016 figure 5E). Few levels may be subjected to soft storey machanism.

3)

OPEN GROUND FLOOR - this denotes soft storey mechanism acting in the building

ROOMS ALONG 2 BAYS SEPRATED BY AN OPEN CORRIDOR - The bays filled with rooms will have higher mass comoared to the middle bay left open for corridor. This includes mass irregularity along with uniformly height.

TWO SHORT SIDES COVERED WITH INFILL WALLS - This means the building left and right sides preiphery is more stiffer during seismic forces(especially along north- south)

STARCASE PORTION AT LEFT TOP CORNER - Usually staircase and lift portions are stiffer than other because of concentrated concrete elements. so the staircase portion contains more stifness in the provided building plan.

NO FRAMING CONNECTION ALONG Y - DIRECTION - we can see that no structural beams are connected in y direction between columns. this makes the building more vulnerable during the north south seismic force.

BEAMS CONNECTED ALONG COLUMN MINOR AXIS - The column are having longer dimension in y- direction. this means they are more stiffer along y dierc tion. But the beams are running along in x direction which wouykd attract much lesser lateral forces and hardly transfers it.

VARIATION IN COLUMN SIZES - The internal column are having higher sizes compored to the exterior column( This is common because of higher load demands). But this will lead to significant diffrence in the lateral drifts of columns. So the concrete floor might have heavy out-of-plane shear which would led to collapse.