Sketch a G+1 residential plan according to Vaastu Shastra and Calculation of Loads as per IS code

Project Name: G+1 Floor Residential Plan in conformance to Vaastu Shastra

Introduction and Aim: The building is designed as required in line with the project name in conjunction with the requirements as per the applicable IS Codes. The building will be constructed at Visakhapatnam Region with Zone 2 Seismic Zones, 50 m/s of wind speed and 50 years design life. This Project design is presented in 6 sections as listed below;

• Given and Problem
• Assumptions
• Sketches
• Codes/ Standards to be used
• Calculations
• Structural Drawing List

Such exercise project is aimed to nourish our practical knowledge on what has been taught under Module 1 of Post Graduate Program in High-Rise Building Design and Analysis course.

I. Given and Problem:

• G+1 Floor Residential to be designed inline with Vaastu Shastra Requirements
• All structural elements to be assumed
• To calculate the individual corresponding loads from the members as per the IS Code
• To list down the needed structural drawings of the Project for Construction to commence

II. Assumptions:

• All columns are 300mm x 300mm denoted as C1 in the sketch provided below.
• All beams are 300mm x 500mm and spanning all throughout the 9 Columns (C1)
• All Slabs having a thickness of 150mm except for Sunken Slabs which. need to deduct 50mm.
• Ground Floor (GF) is 4m in elevation the same with 1^st
• Consider columns as same height with the wall.
• Slab-on-grade to be used on ground base floor.
• Flat Concrete Slab Roofing will be used (it serves as a provision for any future vertical expansion).
• Plinth Beam shall be used same size and orientation as the Tie/ Floor. Beam of First Floor Slab and Flat Concrete Slab Roofing.
• Terrace doesn’t have a wall on its east and south sides.
• All External Walls to consider as stone masonry with a thickness of 300mm same with the columns.
• Interior walls will have a thickness of 120mm brick masonry.
• RCC material will be considered for Beams, Columns and Slabs.
• Finishes Load on walls etc. will not be considered as well as doors, windows, louvers, railings, staircase and including possible installation on the roof.
• Lintels and any needed floating columns are not considered.
• Interlapping deduction between columns, walls, slabs and beams will be negligible as it can considered as part of safety factor.
• Building location is at Visakhapatnam Region of Zone 2 Seismic Zones with 50 m/s of wind speed.

III. Sketches:

You may refer to the attached word file.

Note - All Dimensions are in mm unless specified

IV. Codes/ Standards to be used:

• IS 875:1987 Revised 2003 part 1 for Dead Load (since no revised 2018 available)
• IS 875:1987 Revised 2008 part 2 for Live Load
• IS 875:1987 Revised 2015 part 3 for Wind Load
• IS 1893:2016 part 1 for Seismic Load

V. Calculations:

A. Dead Loads

• Column = RCC Unit Weight * Column Volume * No. of Columns

= (25 kN/m³)(0.3m*0.3m*8m)*9

= 162 kN

• Slabs = RCC Unit Weight * Slab Volume * No. of Slabs

= (25 kN/m³)(((((10.3m*10.31m*2)-(5m²+3m²+3m²+ 5m²))+(10.3m*10.31m))*0.15m)+ ((5m²+3m²+3m²+ 5m²)*0.1m))

= (25 kN/m³)((((212.386m²-16m²)+106.193m²)*0.15m)+(16m²*0.1m))

= 1174.67 kN

• Beams = RCC Unit Weight * Beam Volume * No. of Beams

= (25 kN/m³)((((10.3m*3)+(10.31m*3))*(0.3m*0.5m))*3)

= 695.59 kN

• External Walls = Stone Masonry Unit Weight * Wall Volume

= (24 kN/m³)(((10.3m+10.31m+10.3m+10.31m)*8m)-((2.79m+3.84m)*4M))*0.3m

= 2183.33 kN

• Interior Walls = Brick Masonry Unit Weight * Wall Volume

= (20 kN/m³)((2.94m*2)+4.995m+4.91m+(2.315m*2)+9.7m+(3.041m*2)+1.5m+2.4m+8.67m+(3.94m*2)+

2.91m+0.66m+1.03m+2.38m)*4m*0.12m

= 610.82 kN

Total Dead Loads = 162 + 1174.67 + 695.59 + 2183.33 + 610.82

= 4826.41 kN

B. Live Loads or Imposed Loads

- Uniformly Distributed Load (UDL) of Dwelling Houses from Table 1 IS 875:1987 Revised 2008 part 2 shall be considered. Table 2 from the same IS for the Flat Roof shall be used with access provided.

• All Toilets + Laundry + Walk In Closet + Bedrooms + Dining/Living + Kitchen Live Loads = UDL * Area

= 2.0 kN/m² *110m²

= 220 kN

• Storage + Corridors + Staircase + Yoga Space + Terrace = UDL * Area

= 3.0 kN/m² *71m²

= 213 kN, considering Yoga Space to take same load as Corridors

• Flat Concrete Slab Roofing (access provided) = UDL * Area

= 1.5 kN/m² *(10.3m*10.31m)

= 159.29 kN

Total Live Loads = 220 + 213 + 159.29 = 592.29 kN

• Tabulated distribution of Loads

Load Type	Floor Area (m2)	Dead Load (kN)	Live Load (kN)	Total Loads (kN)	Live Load Uniformed Distribution (kN/m2)	Loads/ Floor Area (kN/m2)
GF	10.3*10.31= 106.19	81+368.21+ 20+231.86+1187.136 +195.984= 2084.19	118+99 =217	2301.19	2.04	21.67
1st Floor	10.3*10.31= 106.19	81+368.21+ 20+231.86+996.192 +414.836= 2112.01	102+114 =216	2328.01	2.03	21.92
Roof	10.3*10.31= 106.19	231.86+398.22= 630.08	159.29	789.37	1.5	7.43
Total		4826 kN	592 kN	5419 kN

Note: Considering no deductions on staircase opening

C. Wind Load

• We shall proceed the calculation even though the current height of the building is not equal or more than 10m, just for the sake of presentation as requested. Building Height at 10m to be considered just for this calculation.
• P_Z = 0.6V_Z², where P_Z is the wind pressure at height z, in N/m²; V_Z is the design wind speed at height z, in m/s
• V_Z = V_Bk₁k₂k₃k₄
• V_B = basic wind speed at locality or region, consider 50m/s taken Fig. 1 of IS 875:1987 Revised 2015 part 3
• k₁ = probability factor (risk coefficient), consider 1.0 taken from Table 1 of IS 875:1987 Revised 2015 part 3 using 50 years as Building Design Life
• k₂ = terrain roughness and height factor, consider 1.0 taken from Table 2 of IS 875:1987 Revised 2015 part 3 using terrain category 2 at height 10m
• k₃ = topography factor, we can simply consider as 1.0 taken from 6.3.3.1 of IS 875:1987 Revised 2015 part 3 assuming upwind slope (θ) of below 3°
• k₄ = importance factor for the cyclonic region, consider 1.0 taken from 6.3.4 of IS 875:1987 Revised 2015 part 3 under all structures category
• So V_Z = V_Bk₁k₂k₃k₄ = 50m/s*1.0*1.0*1.0*1.0 = 50m/s
• Then P_Z = 0.6V_Z² = 0.6(50m/s)² = 1500 N/m² = 1500 Pa
• From 6.3 IS 875:1987 Revised 2015 part 3 Notes: Wind speed may be taken as constant up to a height of 10 m. However, pressures for buildings less than 10 m high may be reduced by 20 percent for evaluating stability and design of the framing.
• With the case of our structure which is at 8m at its current state then the obtained Wind Pressure will be reduced by 20 %.
• So P_Z = 1500*0.8 = 1200 N/m² = 1200 Pa
• Wind load is F = (C_pe– C_pi) A p_d , where p_d is the design wind pressure
• We shall consider p_d = P_Z = 1200 N/m², this is a very safe assumption since it is above 0.7 P_Z
• Let us tabulate below for the elements that are subjected for wind load. Assuming one side of the building covers all entities as one (regardless beams, wall columns etc.). Also considering the side as a flat surface with distortion following the size of wall’s longest span.

Element of the Building	Cpe	Cpi	Cpe – Cpi	(Cpe – Cpi) pd in N/ m2 or Pa	pd in N/ m2 or Pa	F In kN
Left side (a)	0.7	+0.2 -0.2	+0.5 +0.9	+600 +1080	1200	-
Right side (b)	-0.25	+0.2 -0.2	-0.45 -0.05	-540 -60	1200	-
Nort Side (c)	-0.6	+0.2 -0.2	-0.8 -0.4	-960 -480	1200	-
South Side (d)	-0.6	+0.2 -0.2	-0.8 -0.4	-960 -480	1200	-
Local zone (0.25w or 2.58m from edge)	-1.1	+0.2 -0.2	-1.3 -0.9	-1560 -1080	1200	-
Roof	-	-	-	-	1200	108.874

• Cpe can be taken from Table 5 of IS 875:1987 Revised 2015 part 3 with h = 8m, l = 10.31m and w = 10.3m considering only zero-degree wind angle. So h/w = 0.777 and l/w = 1.001
• Cpi can be taken from 7.3.2 of IS 875:1987 Revised 2015 part 3 assuming total opening of the wall is less than 5% of the total wall area. Hence, Cpi values are +0.2 and -0.2.
• The Flat Roof Wind Load can be taken from 7.4.2.1 of IS 875:1987 Revised 2015 part 3;
• F = Cf pd bh, where Cf is the force coefficient and equal to 1.1 (assumed from Fig.4) considering h=8m, b=10.31m and a=10.3m
• So F of Flat Roof = 1.1*1200*10.31*8 = 108.874 kN
• The External and Internal Pressures under “(Cpe – Cpi) pd “will then be distributed to all Load Bearing Building Members such as columns as Wind Load.

D. Seismic Load

• Using the Seismic Coefficient Method (SCM) or Static Analysis Method
• Assumed structure is rigid
• Assumed the fixity of the structure to the ground is perfect
• V_{B =} W*A_H ; where, W = Seismic weight of the building

A_H = Horizontal seismic coefficient

V_B = Design lateral force/ Base shear

• W will be calculated as per 7.4 of IS 1893:2016 part 1.
• No percentage deductions on Live load, hence 100% calculated Live loads is considered.
• Then, W = 5419 kN
• Horizontal Seismic Coefficient A_H = (Z I S_a)/(2Rg), provided for any structure with T<0.1S, the value of A_H will not be taken less than Z/2 whatever be the value of I/R.
• Z = Zone factor, from table 3 of IS 1893:2016 part 1, Z = 0.10 at Zone 2 Seismic Zone.
• I = Importance factor, from table 8 of IS 1893:2016 part 1, I = 1.2 for residential.
• R = Response Reduction factor, from table 9 of IS 1893:2016 part 1, R = 3.0 considering RC Building with OMRF.
• S_a/g = Average response acceleration coefficient, for this you need to determine the “T” or Undamped Natural period of the structure first.
• Solving for T, 7.6.1.c of IS 1893:2016 part 1 shall be used for X and Y directions separately. X will be considered from West to East while Y from South to North direction of lateral forces.
• Tx = (0.09h)/`square root`dx`, where T at x-axis, h (8m) is the building elevation , d<sub>x</sub> (10.3m) is the building width from west to east.
• Tx = (0.09*8)/`square root`10.3`,= 0.2243 sec
• Ty = (0.09h)/`square root`dy`, where T at y-axis, h (8m) is the building elevation , dy (10.31m) is the building width from south to north.
• Ty = (0.09*8)/`square root`10.31`= 0.2242 sec
• Consider that the building is located at Type II (Medium Soil)
• From Fig. 2a of IS 1893:2016 part 1 with Tx = 0.2243 sec and Type II Soil then S_a/g = 2.5.
• A_H = (Z I S_a)/(2Rg), at X- Axis
• A_H = ((0.1*1.2)/(2*3))*2.5 = 0.05
• V_{B =} W*A_H @ X-Axis
• V_{B =} 5419*0.05 = 270.95 kN @ X-Axis
• Looking from above result, we can simply conclude that for this building the design seismic force in Y-direction is same as that in the X-direction. Fig. 1.2(b) shows the design seismic force on the building in the Y-direction.
• Also the design base shear is to be distributed with height as per 7.6.3 of IS 1893:2016 part 1

VI. Structural Drawing List:

• Center Line Drawing
• Footing and Column layout with reinforcement details
• Column Schedule with reinforcement details
• Plinth beam layout with reinforcement details
• First floor beam layout with reinforcement details
• First floor slab layout with reinforcement details
• Roof beam layout with reinforcement details
• Roof slab layout with reinforcement details
• Staircase and Headroom reinforcement details