Design Report- Prestige

Project: PRESTIGE NOTTING HILL Owner: PRESTIGE ESTATE PROJECTS PVT (LTD)

PROJECT:

PRESTIGE NOTTING HILL

DESIGN REPORT-1

CLIENTS: PRESTIGE ESTATE PROJECTS PVT (LTD)

ARCHITECTS:VENKATARAMANA ASSOCIATES

STRUCTURAL CONSULTANTS:


CONTENTS

1. GENERAL INFORMATION

2. DESIGN DATA

3. DESIGN BRIEF

3.1 PROJECT DETAILS

3.1.1 General Description

3.1.2 Structural System

3.1.3 Design Philosophy

3.1.4 Structural System for the Main Building

3.2 TECHNICAL NOTES

3.2.1 Design Codes & References

3.2.2 General

3.2.3 Design loads

3.2.4 Design Dead loads

3.2.5 Design Live Loads

3.2.6 Wind Load

3.2.7 Earthquake load

3.2.8 Strength of Materials

3.3 DESIGN CRITERIA

3.3.1 Basic Assumption

3.3.2 Limit State Method of Design

3.3.3 Load Factors

3.3.4 Serviceability Check

3.4 COMPUTER ANALYSIS OF STRUCTURE


PROJECT:


GENERAL INFORMATION


ARCHITECTS:VENKATARAMANA ASSOCIATES



GENERAL INFORMATION

1. NAME OF PROJECT : PRESTIGE NOTTING HILL

2. LOCATION OF PROJECT : BANNERGHATTA ROAD, BANGALORE

3. NAME & ADDRESS OF OWNER: PRESTIGE ESTATE PROJECTS PVT (LTD)

4. NAME & ADDRESS OF DESIGN CONSULTANTS:

A. ARCHITECTS: VENKATARAMANA ASSOCIATES.

B. STRUCTURAL CONSULTANTS:

CHETANA CONSULTANTS#905, A-WING, 9TH FLOOR, MITTAL TOWER,#6, M.G. ROAD, BANGALORE.

5. NAME OF PERSON RESPONSIBLE FOR INTERACTING WITH PEER REVIEW CONSULTANT AND HIS CONTACT TELEPHONE NUMBER /E-MAIL ID / FAX NUMBER ETC. :

DINESH BELLADASSOCIATE CONSULTANTCHETANA CONSULTANTSMOB No: 98860 58823EMAIL: checon @ vsnl.comFax: 080 – 25596053

6. TERMS OF REFERENCE (BROADLY) GIVEN TO THE DESIGN CONSULTANT BY THE OWNER.


PESTIGE NOTTING HILL

SN Block Name No. of Floors as per Architecture plans

1 TOWER-A B+STILT+15 FLATS

2 TOWER-B B+STILT+16 FLATS

3 TOWER-C B+STILT+16 FLATS

4TOWER-D

B+STILT+16 FLATS

5 TOWER-E B+STILT+16 FLATS


PROJECT: PRESTIGE NOTTING HILL

,

DESIGN DATA (To be confirmed by Clients / Architects)

CONSULTNG STRUCTURAL ENGINEERSA-905, 9th Floor, Mittal Tower, No. 6, M.G. Road, Bangalore – 01.Ph: 5597667, 5583993. Fax: 5596053E-mail: [email protected]


(Confirmed by Clients / Architects)

PROJECT : PESTIGE NOTTING HILL DATE:

JOB No. :

ARCHITECTS : VENKATARAMANA ASSOCIATES.

CLIENTS : PRESTIGE ESTATE PROJECTS PVT (LTD)

1.0 SOIL TEST REQUIREMENTSNO. OF BORE HOLES :

2.0 NO. OF FLOORS FOR DESIGN(AS PER SCHEDULE)

3.0 LOADING DATA

3.1 WALLS

EXTERNAL WALLS

200 THK SOLID CONCRETE BLOCK MASONRY

INTERNAL WALLS


AROUND TOILETS


PARAPET150 THK SOLID CONCRETE

BLOCK MASONRY

24 07 2007

13 – Bore holes

B STILT FLOORS

1 1 16 MAX


3.2SUNKEN SLAB

3.2.1 TOILET SINKING(General)

3.2.2 BALCONY SINKING(BALCONY & UTILITY)

3.3 TOILET SUNKENSLAB BACKFILL

3.4 O.H. WATER TANKS

No. of Tanks Capacity in Ltrs. PositionFire + Domestic ( indicate by grids or any reference)

Two in each tower 75 cumec capacity As per architectural drawing

3.6 GARDEN LOAD:

3.7 FIRE TENDER LOAD

3.8 TRANSMISSION

TOWER

4.0 DATA CONFIRMED BY :

1. ARCHITECT'S REPRESENTATIVE …………………………

2. CLIENT'S REPRESENTATIVE …………………………

3. CHETANA CONSULTANT'S REPRESENTATIVE …………………………

100 MM

100 MM

BRICKBAT

Location

Terrace Nil

Penthouse Terrace Nil

Podium Slabas per landscape drawing

Max-750 fill

Over podium slab 46T GROSS Fire Tender Load is considered for design

Location Load

- -


PPROJECT:


DESIGN BRIEF


ARCHITECTS: VENKATARAMANA ASSOCIATES



3.1.1 PROJECT DETAILS :

3.1.1 GENERAL DESCRIPTION:

PRESTIGE ESTATE PROJECTS PVT (LTD) is set up a Residential Apartment at the site located at Bannerghatta Road, Bangalore, Inda integrating 2 bed room, 3 bed room, apartments.

3.1.2 STRUCTURAL SYSTEM:

3.1.3 DESIGN PHILOSOPHY :

The basic structural material chosen for most of the structural elements in the building is

reinforced concrete. In recent years reinforced concrete structures developed personalities of

their own, reflecting inherent homogeneous characteristics including its strength, mouldability,

fire safety, handsome appearances and weather resistances. The building is proposed to be

designed as reinforced concrete framed construction with shear wall.

The function of a building has a considerable effect on the selection of structural type. Several

alternate framing systems have been studied in order to achieve a suitable structural pattern.

The variety of the types of the floor system that can be constructed with reinforced concrete

enable selection of the most economical design satisfying the functional requirements of the

building with all possible loads that can come on building during its life time.

Many services are usually carried through vertical shafts and distributed horizontally and the

slab beam system may be selected for structural efficiency and economy.

The slab beam system can efficiently handle all the gravity loads. To take care of the lateral

loads, column-beam framing with shear wall action is utilized to transfer lateral loads in

addition to gravity loads. After several discussions with Architects & Service Consultants &

Cost Effectiveness slab beam system is proposed & approved for the project.

3.1.4 STRUCTURAL SYSTEM OF THE MAIN BUILDING :

Page-1 of 12


1 SUPER STRUCTURE: Super structure of the main building is a slab beam system. The

beams & columns are so arranged as to divide the area into regular rectangle & square

panels. The slabs are either one way or two way slabs.

The arrangement of the beams & columns is determined by economical & functional

considerations which are further dependent upon the use to which the building is put, the size

& shape of the floor & load.

The Ground floor slab has been designed for parking loadings with slab & beam system and

typical floor slab in tower portion has been designed for residential loadings and podium slab

has been designed for landscape loadings with hard surface finish and fire tender load with

slab beam system.

Since the slab, beams are cast monolithically the advantage is taken of rigidity of members &

continuity to distribute the loads in orthogonal directions.

1 SUB STRUCTURE:

The soil investigation report was submitted by F.S. Engineer Pvt. Ltd Chennai., and Chetana

Consultants had recommended to take second opinion for the SBC of the soil. Prof. B.R.

Srinivasa Murthy of IISc Bangalore has inspected the site and submitted their

recommendations. Based on this report SBC of 40 MT/Sqm is considered for Design of

Foundations.

Sub structure consists of isolated, combined footings & raft foundation which distribute gravity

loads & lateral loads from super structure to soil beneath.

3.2 TECHNICAL NOTES:

3.2.1 DESIGN CODES AND REFERENCES:

.1 Indian Standard Code of Practice for Design Loads (other than Earthquake) for buildings

and structures. IS: 875 (Part 1) 1987.

.2 Indian Standard Code of Practice for Design loads (other than Earthquake) for buildings

and structures. IS: 875 (Part 2) – 1987.

.3 Indian Standard Code of Practice for Design loads (other than Earthquake) for buildings

and structures. IS: 875 (Part 3) – 1987.

.4 Indian Standard Plain and Reinforced Concrete. Code of Practice. IS: 456 : 2000.

.5 Indian Standard Criteria for Earthquake Resistant Design of Structures IS:1893(Part.1) :2002.


.6 Indian Standard code of practice for Earthquake Resistant Design and construction of

buildings (2nd Revision) IS: 4326 – 1993.

.7 Indian Standard Code of practice for concrete structures for the storage of liquids IS:

3370 (Part II) – 1965.

.8 Indian Standard code of practice for concrete structures for the storage of liquids IS: 3370

(Part IV) – 1967.

.9 SP-16 – 1980, Design Aids for reinforced concrete to IS: 456 – 1978.

.10 SP: 24 – 1983. Explanatory Hand book on Indian Standard Code of Practice for Plain

and Reinforced Concrete to IS: 456 – 1978.

.11 Indian Standard Hand Book on Concrete Reinforcement and Detailing SP: 34 (S & T) –

1987.

.12 Foundation Analysis and Design – Joseph E Bowles – McGraw-Hill Publications.

.13 Reinforced Concrete Designer’s Hand Book – C.E. Reynolds and James C. Steedman.

.14 Practical Design of Reinforced Concrete – Russel S Fling.

.15 Hand Book of Concrete Engineering – Mark Fintel – CBS Publishers and Distributors.

.16 Design of Reinforced Concrete Structures for Earthquake Resistance Eng. D.S. Joshi

and Eng. R.L. Nene, Eng. M.D. Mulay, Eng. Suresh Salgaonkar, Eng. Neelkanth D. Joshi

Indian Society of Structural Engineers.

.17 Properties of Concrete – A.M. Neville – The English Language Book Society and Pitman

Publishing.

3.2.2 GENERAL

.1 Structural drawings shall be read and used in conjunction with Architectural, Mechanical,

Plumbing, Electrical drawings and project specifications.

.2 Unless otherwise noted, details shown on any structural drawings are to be considered

typical for all similar conditions.

.3 All levels to be read from Architectural drawings & corresponding services drawings.

.4 All dimensions in structural drawings, reinforcing bar diameters / spacing of bars are in

millimeters.

3.2.3 DESIGN LOADS

Page-2 of 12


3.2.4 DESIGN DEAD LOADS – IS 875: Part 1

.1 Self Weights

Self weight of the structural members will be considered on the basis of the following criteria.

Density of reinforced concrete 25 kN/ cu.m

Density of soil 20 kN/ cu.m

Density of steel 80 kN/ cu.m

Density of plain concrete 22 kN/ cu.m

Density of finishes / plaster 20 kN/ cu.m

Density of Granite 28 kN/ cu.m

Density of Solid blocks 22 kN/ cu.m

Density of Cinder for filling 8 kN/ cu.m

Density of Brickbat filling 18 kN/ cu.m

Density of Brickbat filling with interstices filled with mortar 20 kN/ cu.m

.2 Dead Loads

100 thk Partition walls (Solid Concrete Block) 3.0 kN/sq.m( Including plastering on both faces 40mm thk)

Floor finishes 1.50 kN/sq.m

200 thk Wall loads (Solid Concrete Block) 4.4 kN/sq.m

Terrace level Waterproofing (Avg. 150mm thk.) 3.00 kN/sq.m

3.4.5 DESIGN LIVE LOADS – IS 875: Part 2

FLOOR INTENDED USE LIVE LOAD (in KN/sqm.)

Basement Parking Directly on to foundation (Grade slab)

Ground Floor Parking 3 kN/m2

Typical Apartment Residential use Live Loadsfloor Rooms, Verandah, Kitchen,

Dining, Toilet & Bathrooms, 2.0 kN/Sq.m.Utility

Corridors, Passages, StaircasesIncluding Fire escapes and 3.0 kN/Sq.m.Store rooms, Entrance lobby

Balconies 3.0 kN/Sq.m.Sunken Loadings Sunk Loads

Toilets 100 mm Brickbat filling 18 kN/cum.


Balcony 100 mm - “ -

Garden 750mm Soil fillingFire tender 46T Gross Axle Load

First floor to Sixteenth floor Residential use Roomwise Live Load

Terrace Integrated water proofing 3.0 kN/Sq.m. + Live Load 1.5 kN/Sq.m.

Lift Machine Room floor as per lift man 10.0 kN/sq.m

Fire Tender where applicableWheel / Axle Load – IRC Class A46 MT for Design of pavementspodium and where ever applicable.

3.2.6 WIND LOAD

As per IS.875 part 3 1987 Basic wind speed at Bangalore 33 M/sec is considered as per

Appendix A.

Basic Wind Speed = 33 m/s [ Appendix – A, Clause – 5.2 ] (Bangalore) @ 10m height IS:875 (Part-3) – 1987

Design Wind Speed (Vz)= Vb K1 K2 K3 – Cause – 5.3.c [ IS-875–(part-3)–1987]@ any height Z (m/s)

K1 = Probability factor = 1.0 – [ Table-1 – Clause-5.3.1 ]

K2 = Terrain, heigt &Structure size factor = Class C – [ Clause 5.3.2.2 – C ]

K3 = Topographic factor = Category-2 – [ Clause-5.3.2.1 – (a) ]= 2.0 – [ Clause 5.3.3.1 ]

Vz = 33 × 1 × 1.114 × 2 = 73.52 m/s

Design Wind Pressure (Pz) = 0.6 Vz2 – [Clause-5.4]

(Pz) = 0.6 × (73.52)2

= 3243.11 N/m2

(Pz) = Design Wind Pressure in N/m2 @ height Z

Height (m) Upto 10 15 20 30 50 60 100

(K2) 0.93 0.97 1.00 1.04 1.10 1.114 1.17

As per landscape drawings


Height Design Wind Speed Design Wind Pressure Floors h (m) Vz (m/s) Pz (N/m2)

Upto 10m 61.38 2260.5

15 64.02 2459.1

20 66.00 2613.6

30 68.64 2826.8

50 72.60 3162.5

60 73.52 3243.1

100 77.22 3577.8

Further to Design Wind Pressure (Pz) appropriate pressure co-efficient will be used as

applicable.

Wind loads on cladding / glazing:

For designing the cladding / glazing supports, the wind load will govern the design, for which

the above design wind pressure to be considered with appropriate local pressure coefficient.

3.2.7 EARTH QUAKE LOAD: IS 1893 / IS 4326 / IS 13920

Earth quake loads are calculated as per seismic co-efficient method as suggested in IS 1893-

(Part 1) - 2002.

According to the IS Code 1893, the Indian Sub-Continent has been divided into five seismic

zone. Zone I and II are zones of “Low Seismic Risk”. IS 1983 which has been revised

recently had bought change in the seismic zone map. Zone I has been merged with Zone II.

Bangalore which was in zone I has been moved to Zone II.

Ductile detailing as given in IS 456 is followed.

Design Spectrum

The design horizontal seismic co-efficient for a structure shall be determined by the following

expressions. ( As per cl. 7.8.2 & 7.6 )

Ah = ZI Sa2R g

Z – Zone factor for Zone II– Low Seismic Intensity = 0.10

I – Importance factor = 1.0

R – Response reduction factor for ordinaryShear Wall with Moment resisting frames = 3.0

Sa – Average response acceleration co-efficient which depends on soil


G types, natural period and damping values.

T – Fundamental Natural period = 0.075h 0.75

Where ‘h’ is the height of the building (App. 57 meter)

Assuming hard soil and damping 5%.

T = 1.56

(Sa / g ) = 1.05 / T = 0.675

A h = 0.1 1 0.675 = 0.011 2 3

3.2.8 STRENGTH OF MATERIALS

3.5.1 STEELAll reinforcing steel shall be high yield strength deformed bars of grade Fe 415 for rebars upto 10mm and Fe 415 for rebars of diameter 12mm and above.

3.5.2 Y – on all drawings represents high yield strength deformed bars.

3.2.9 DESIGN OF CONCRETE ELEMENTS

IS 456 : 2000 Plain and re-inforced concrete code of practice.

IS 1786 Specification for high strength deformed steel bars and wires forconcrete reinforcement

SP 16 Structural use of concrete design charts for singly re-inforced beams and columns.

SP-7 (Part IV) National Building Code of India.

.1 DESIGN OF FOUNDATIONS

IS 1904 Indian Standard Code of Practice for design & construction foundation in soil general requirements.

IS 2950 Indian Standard Code of Practice for design & construction of raft foundation (Part-1).

IS 2974 Code of Practice for design & construction of machine foundation.

SP 34 Handbook on Concrete Reinforcement.

.2 WATER TANK

IS 3370 (Part-1) Code of Practice for Concrete Structure for the Storage of Liquids.


.3 CONCRETE

Grade of concrete shall be as follows:

COLUMNS

Grade of concrete for all columns, shall be as per schedule.

FOUNDATION, RETAINING WALLS & OTHER CONCRETE BELOW GROUND LEVEL.

For above structural elements with concrete grade M 30 with minimum cube strength of

30 N/mm2 at 28 days with minimum cement content of 350 Kg/m3.

GROUND FLOOR LEVEL TO TERRACE LEVEL FOR SLAB & BEAMS

Concrete grade M20 with minimum cube strength of 20 N / mm2 at 28 days with minimum

cement content of 300 Kg/Cum. Podium Slabs and beams shall be of M25 grade concrete

with minimum cube strength of 25 N/mm2 at 28 days with minimum cement content of 325

Kg/Cum

.4 LAP LENGTH

Lap length shall be for M20 – 47 × dia.

M25 – 40 × dia.

M30 – 40 × dia.

M35 – 40 × dia.

M40 & above – 40 × dia

.5 CONCRETE COVER

Clear concrete cover to reinforcement for:

Solid slabs 15 mm

Isolated/Combined Footings 50 mm

Retaining Wall 20 mm / 25 mm on earth side

Beams 25 mm

Columns 40 mm

RC walls (Water tanks) 20 mm / 30 mm on earth / water side

Staircase 15 mm

Fire Staircase 20 mm

Shear wall 20 mm

Raft slab Bottom / sides 75 mm

" Top 50 mm

Grade Slab 20 mm

.6 FOUNDATION


.1 Maximum allowable loading intensity on soil is taken as 40 T/m2 up to 1.5m as per Geotechnical Investigation report.

.2 All loose pockets and soft spots are to be filled in mass concrete grade M10.

.3 Backfilling behind the retaining walls shall be carried out only after the ground floor slab is cast and has attained designed strength.

.4 All backfilling shall be well compacted to achieve 95% modified dry density compaction in layers of not more than 300mm.

.7 SUPER STRUCTURE

.1 Concreting of columns, beams, fascias and thin sections of concrete members shall be carried out using approved plasticiser as per manufacturers specifications.

.2 Concrete pouring, testing, removal of formwork and acceptance criteria shall be as per relevant latest Indian Standard code of practice.

.3 Centering of cantilever beams and slab projections shall not be removed unless roof slab above is cast and cured and sufficient balancing load is attained.

.4 Before pouring floor level concrete, the floor systems below shall be sufficiently supported by means of propping and this system shall be approved by the Engineer-in-charge.

.5 Contractor shall check all the openings as per Architectural / Service drawings and shall provide necessary trimming bars. No additional opening shall be drilled in the structure unless approved.

.6 Construction joints in slabs and beams are often placed either at point of contraflexure in which case the concrete may be left sloped off or stepped off by means of stop forms. Construction joints located near minimum shear shall have stop forms perpendicular to the acting forces. Where the concrete is to be placed in the second pour, the old concrete shall be thoroughly moistened and a layer of rich fresh mortar should be laid immediately before fresh concrete is placed. It should be placed to a thickness of 20-30mm and shall be worked well into the irregularities of hardened concrete.

.7 All the construction joints shall be pre-determined as per the sequence of operation and shall be got approved.

.8 Columns form should be made so as to avoid dropping of concrete from top. The one side of forms shall be divided in lifts not exceeding 3 m height.

.9 Concrete should be placed in thin layers, which can be effectively compacted as the placing proceeds say in 300mm.

.10 When casting columns, walls or beams of depth 700mm or more, a layer of rich cement mortar should be placed first. This is to avoid accumulation of gravel in the bottom layer and to have a better bond.

.11 Compaction of concrete shall be done by mechanical vibrators. Proper care shall be taken to avoid segregation and honeycombing.

.12 The secondary beam bars shall be placed over main beam bars when the depths of beams are same at junctions.

.13 Short span steel shall be at bottom layer in two way slab system and spacers, bar supports to top steel shall be provided with adequate cover.

.14 No splicing of bars shall be made at the point of maximum tensile stresses.


.15 At the ends of beam, both top and bottom steel should terminate at 90 degree bend to a minimum anchorage length of 40 D.

.16 For splices of reinforcement, full bond length shall be used. Minimum LAP length for compression bars – 40 D and tension bars – 50 D.

.17 Not more than 1/3rd of main reinforcement shall be lapped at any section.

.18 Splices if unavoidable must be located from face of the column at not closer than twice the beam depth.

.19 Splices in beams shall be contained by additional 3 Nos. of stirrups.

.20 Stirrups shall be closed type with ends hooked.

.21 Spacing of stirrups shall not exceed half the effective depth.

.22 Integral water proofing system shall be adopted for toilet sunken slab & terrace slab as per specification.

.8 EXPANSION JOINTS / SEPARATION JOINTSAll towers and podium shall be separated by an Expansion joint of 25mm.

3.3 DESIGN CRITERIA

3.3.1 BASIC ASSUMPTION

1.1 The building is designed as one rigid monolithic structure in which joints in beams and columns have been assumed to be fixed in position but free to rotate in direction.

1.2 Sizes of structural elements have been so fixed so as to produce full stresses.

1.3 Since load carrying capacity of compression members increase with richness of concrete mix and for the sake of economy the higher grade of concrete is proposed for columns.

1.4 Continuity of structural members is very much desirable since it will provide multiple path of load resistance. Therefore as far as possible all parts of building are tied together to act as one unit in resisting external forces.

1.5 The floor slabs are considered as horizontal diaphragms and are stiff enough in their planes to produce equal lateral displacement at floor levels.

1.6 The entire structure is considered as “Gravity load framed construction” in which entire lateral load is carried by frame action with shear wall actions.

1.7 Concrete behaves linearly elastic and therefore the structure is amenable to a linear method of analysis involving super-position of actions and displacements.

1.8 The cladding and non-structural components do not influence the behavior of the building.

1.9 The shear deformation of slender flexural members and torsional stiffness of slender beams, columns, plane walls, are insignificant.


1.10 The out of plane action of slabs and out of plane action of walls of frame bents are to be disregarded.

1.11 The axial deformation of vertical elements is disregarded.

3.3.2 LIMIT STATE METHOD OF DESIGN

Limit state method of design has become major design method in which in elastic

behavior is considered rather than considering only elastic behavior as per working

stress design theory. This method helps to close the gap that exists between the

strength computations and actual test result. In view of this, all the structural elements

in the building are proposed to be designed with “LIMIT STATE METHOD” as per

Indian standards.

3.3.3 LOAD FACTORS

LOAD COMBINATIONS USED FOR THE ANALYSIS

Load Combinations Remarks

1.5 (DL+LL) DL = Dead Load of The Structure LL = Seismic %age Live Load on the

structure Eqx = Earthquake Load along X direction Eqz = Earthquake Load along Z direction Wx = Wind Load along X direction Wz = Wind Load along Z direction

1.5 (DL+ Eqx) 1.5 (DL + Wx)

1.5 (DL + Eqz) 1.5 (DL + Wz)

(0.9 DL + 1.5 Eqx) (0.9DL + 1.5 Wx)

(0.9 DL + 1.5 Eqz) (0.9DL + 1.5 Wz)

1.2 (DL+ LL + Eqx) 1.2 (DL + LL + Wx)

1.2 (DL + LL + Eqz) 1.2 (DL + LL + Wz)

3.3.4 SERVICEABILITY CHECK

This is given with following limitations:

a. For deflections : Total load deflections = Span / 240

Vertical : Live load deflection = Span / 360

b. Lateral drift : = Span / 500

c. For Cracking

i. Surface crack width shall not exceed in general = 0.3 mm

ii. For water retaining structure = 0.2 mm

3.4 COMPUTER ANALYSIS OF THE STRUCTURE The above structure is analysed using STAADPro software.

Documents

Design Report- Prestige