Petronas TowersMenara Berkembar PetronasPetronas TowersPresented By Deepika Dhilip Reg No:2014804005The Petronas Towers, also known as the Petronas Twin Towers (Malay: Menara Petronas, or Menara Berkembar Petronas), are twin skyscrapers in Kuala Lumpur, Malaysia.

Record height - Tallest in the world from 1998 to 2006General informationConstruction period : 3 years i.e. march 1993-march 1996Type - Commercial offices, Retail, Hotel, Parking for 6,650 carsArchitectural style - PostmodernLocation - Jalan Ampang, Kuala Lumpur, MalaysiaHeight Architectural - 451.9 m (1,483 ft)Roof - 378.6 m (1,242 ft)Top floor - 375 m (1,230 ft)Technical detailsFloor count - 88 (+5 basement floors)Floor area - 395,000 m2 (4,252,000 sq ft)Lifts/elevators - 78Design and constructionArgentine American ArchitectCsar Pelli.Twin skyscrapersinKuala Lumpur, Malaysia

The 88-floor towers are constructed largely of reinforced concrete, with a steel and glass facade designed to resemble motifs found inIslamic art, a reflection of Malaysia'sMuslimreligion.The Petronas Towers feature a diamond-faceted facade consisting of 83,500 square meters (899,000sq.ft.) of stainless steel extrusions. In addition, a 33,000-panel curtain wall cladding system resides within the towers.the stainless steel element of the towers entices the illustrious sun, highlighting the magnificent towers, they are composed of 55,000 square metres (590,000sqft) of 20.38-millimetre (0.802in) laminated glass to reduce heat by reflecting harmful UV rays.The towers feature a double deckerskybridgeconnecting the two towers on the 41st and 42nd floors.The bridge is 170m (558ft) above the ground and 58m (190ft.) long, weighing 750 tons.The main bank ofOtisLiftsis located in the center of each tower. All main lifts aredouble-deckerwith the lower deck of the lift taking passengers to even-numbered floors and upper deck to odd-numbered floors. To reach an odd-numbered floor from ground level, passengers must take anescalatorto the upper deck of the lift.On the top of each tower is a pinnacle standing 73.5 metres (241ft) tall.Each pinnacle is composed of 50 unique parts making up the main components: the spire, mast ball and ring ball. Together these parts weigh 176 tons.The interiors of the towers highlight the Malaysian cultural inspiration to the design through traditional aspects such as fabric and carvings typical of the culture, specifically evident in the foyer of the entrance halls in the towers.

Introduction

A tall building requires an efficient vertical transportation system typically comprising passenger lifts, service lifts and fireman lifts. The number of passenger lifts is generally determined by the population of the building, type of building occupancy, population during peak period, number of floors and heights, and building location in relation to public transport services. More specifically it depends on the quality of service, round-trip time, flow rate, interval for lifts, lift travel and lift speeds. Generally when the building becomes taller, additional lifts are required to accommodate the additional population. The lift arrangement has a major impact on the size and internal layout of the service core which, in turn, affects the net rentable floor area. Therefore an economic design should aim at striking a proper balance between the passenger handling capability and rentable floor space.For a tall building, the vertical transportation system is usually based on the multi-zone system in which the building is divided into a number of lift zones such as low, mid and high zones. Prospective passengers take lifts at the main lift lobby to reach a destination floor.However, for a super tall building, the size of the service core becomes excessively large. In order to keep the service core within a reasonable size while maintaining an acceptable level of response time, the sky-lobby system may be adopted as a solution.Passengers take shuttle lifts to the sky-lobby and then transfer to other lifts to higher floors.Vertical Transportation System

Another solution to keep the service core within a reasonable size is the double-deck lift system. Two lift cabs are stacked vertically in a common lift frame and thus increase the passenger handling capacity. When compared with the conventional lift system, this significantly reduces the number of lift shafts, but new users may find this system confusing unless there are adequate directional signage's. In addition, it may also be used with the sky-lobby system to further reduce lift shafts at the lower floors. The best example of this system is the 88-storey Petronas Towers ( 1 and 2 )in Kuala Lumpur in which the vertical passenger transportation system is divided into lower floors (floors 8 37) and upper floors (floors 44 - 83) with sky-lobbies at floors 41 and 42. Within both the lower and upper floors, it is further divided into low, mid and high lift zones. Lower and upper floors are each served by twelve double-deck lifts and sky lobbies are served by five double-deck shuttle lifts. In many Asia Pacific cities, the passenger lift is not considered as a means of escape in case of fire and thus a firemans lift is required to serve all usable floors.In addition, a building also normally requires one or more service lift for transportation of goods to various floors. In order to reduce the number of lift shaft, one of the service lifts is often designed for dual-use as a fireman/service lift.

Each tower has one central core for all lifts, tower exit stairs and mechanical services. Satellite bustle stairs have non-structural walls, since they would be less effective cores (see Figure 3).For the PETRONAS Twin Towers, two virtually solid walls running North-South, and one running East-West, provide `Webs', for the core `cantilever beam', making the core quite stiff and efficient.As a result, it carries slightly more than half the wind overturning moment at the foundation. To resist wind the core has thick, heavily reinforced corners (see Figure 4). The overall core varies from about 23 m (75 ft) square to 19622 m (62673 ft) in four steps, with outer walls varying from 750 mm (30 in.) to 350 mm (14 in.) and inner walls a constant 350 mm (14 in.) to avoid complications with lift shafts and the self-climbing forming systems.Above level 70, corners of the core drop back to avoid `pinching' office circulation against the perimeter columns. Concrete grade varies in three steps from 80 to 40 Mpa, matching tower column grades (see Figure 5).CORE

VERTICAL TRANSPORTATION PLANCentral CoreCentral core in each tower, accommodate lifts, exit stairs, mechanical servicesTwo solid walls running n-s and e-w- web cantilever beams projecting-makes it stiff takes more than half the twisting moment.Highly reinforced thick corner walls- resist wind.Core varies from 22 sq m to 19 x 22 m in four steps Outer walls 750 to 350 mmInner walls constant 350 mm- to avoid complication with lift shaft concrete grade drops from 80 -40 mpa as it accents

VERTICAL TRANSPORTATION PLAN

VERTICAL TRANSPORTATION PLAN

SKYBRIDGEA double-deck bridge spanning 58.4m (190 ft.) connects the two towers at the sky lobby elevator transfer stations on floors 41 and 42, 170 m (558 ft.) above grade, for easy circulation between upper tower floors with a minimum of lift transfer and possible crossover exiting through the other tower, reducing the required size of exit stairs below (see Figure 8).Because of the great height and span, structural steel was used for lightweight and easier construction. Although single-span trusses could have been used, a two-hinged arch and continuous floor girders offered a shallow walkway structure, minimized expansion joint movement (joints move at both towers), self-centering action from restraint at the arch crown and a strong visual identity. The skybridge design considered the effect of complex tower movements on joints and members, including vertical midspan movements due to tower deflections, the aerodynamic response of the 1.1m (3.6 ft.) diameter pipe legs, fatigue, the response to sudden loss of support, creep and shrinkage movement and compensation, and bridge facade panel movements.

Lift systemThe main bank of Otis Lifts is located in the center of each tower. All main lifts are double-decker with the lower deck of the lift taking passengers to even-numbered floors and upper deck to odd-numbered floors. To reach an odd-numbered floor from ground level, passengers must take an escalator to the upper deck of the lift.There are 29 double-deck passenger elevators, but there are different sets that service certain floors of the towers, specifically two sets of six of these double-deck passenger elevators to floors 123 and 137 respectively. Another set of 5 passenger lifts transport passengers to the 41st and 42nd floors where they can switch lifts to reach the upper zones of the buildings, each double-deck passenger lift with the capacity of 52 passengers or, 26 passengers per deck. There are also 6 heavy-duty elevators for utility.From the ground floor, there are three groups of lifts. The "short haul" group of 6 lifts take passengers to floors between level 2/3 and level 16/17. The "mid haul" group of six lifts take passengers to floors between level 18/19 and level 37/38. There is also a set of shuttle lifts that take passengers directly to levels 41/42. To get to levels above 41/42, passengers must take the shuttle lifts, then change to lifts to the upper floors. These connecting lifts are directly above the lifts that serve levels 2 to 38. The pattern now repeats with the upper levels, one set serving levels 43/44 to 57/58 and one set serving levels 59/60 to levels 73/74.[41]Apart from this main bank of lifts, there are a series of "connecting" lifts to take people between the groups. Unlike the main lifts, these are not the double-decker type. Two lifts are provided to take people from levels 37/38 to levels 41/42 (levels 39 and 40 are not accessible as office space). This spares someone in the lower half of the building from having to go back to the ground floor to go to the upper half of the building.The lifts contain a number of safety features. It is possible to evacuate people from a lift stuck between floors by manually driving one of the adjacent lifts next to it and opening a panel in the wall. It is then possible for people in the stuck lift to walk between lift cars.During an evacuation of the buildings, only the shuttle lift is allowed to be used, as there are only doors at levels G/1 and levels 41/42; therefore should there be a fire in the lower half of the building, this enclosed shaft would remain unaffected. Firefighter lifts are also provided in case of emergency.

Shuttle Lifts (with sky lobbies)Many tall buildings are divided into several zones: low zone, mid zone, high zone, etc. with service direct from the main terminal floor, situated at ground level. These are called `local zones. This becomes impractical with very tall buildings and shuttle lifts are employed to take passengers from the ground level main lobby to a `sky lobby'. This could be 200 m (Petronas Towers, Kuala Lumpur, Malaysia).Passengers disembark at the sky lobby and service is then provided to further low, mid, high zones, etc. using the sky lobby as an upper main terminal floor.The advantage is that the core efficiency is improved, as the hoist ways extend the whole height of the building (except for the intervening equipment spaces) and occupy the same hoist way `footprint'. Shuttle lifts are usually quite large and fast and provide an excellent service to the sky lobby. Their main disadvantage is that the passengers must change lifts mid journey, hence increasing their total journey time. When a traffic design involves a change of lift, the two journey times are best quoted separately. Sometimes passengers travel down from the sky lobby as well as up (Fortune, 1986). Most shuttle lifts are single deck, but there are a number of double deck installations.Generally shuttle lifts serve between two stops only, hence the term `shuttle', but sometimesthey serve three stops, ie: with two sky lobbies (Sears Tower, USA).The number of shuttle lifts that are installed world wide is not large. Their traffic design isrelatively simple, but their application in a building requires expert consideration.

Shuttle Lifts (with sky lobbies)3. Double deck shuttles, double deck locals, eg: Petronas Towers, Malaysia.

Double Decker LiftsDouble deck lifts comprise two passenger cars one above the other connected to one suspension/drive system. The upper and lower decks can thus serve two adjacent floors simultaneously. During peak periods the decks are arranged to serve `even' and `odd' floors respectively with passengers guided into the appropriate deck for their destination. Special arrangements are made at the lobby for passengers to walk up/down a half flight of stairs/escalators to reach the lower or upper main lobby.Double deck lifts, which are common in the USA and elsewhere, but unusual in Europe, are used in very tall buildings. Fortune (1996) indicated 465 double deck lifts in 34 buildings across the world (see Table 1).There are many advantages and disadvantages to double deck operation and special care has to be taken with the lobby arrangements. One advantage for double deck lifts is that the `hoist way' handling capacity is improved, as effectively there are two lifts in each shaft. A disadvantage for passengers during off peak periods is when one deck may stop for a call with no coincident landing, or car call, required in the other deck. Special traffic control systems, available during off peak periods, attempt to overcome this problem.

and the disadvantages as:1. One significant supplier2. Passenger misuse3. Zone populations must be large4. Balanced demand from even and odd floors5. Interfloor distance must be regular6. Slightly larger hoistways7. Increased pit and machine room loadings8. Lobby exits need to be larger9. Special facilities for disabled access to other floorFortune (1996) expounds the advantages of double deck installations as:1. Fewer lifts2. Smaller car sizes3. Lower rated speeds4. Fewer stops5. Increased zone size6. Quicker passenger transit times7. 30% less core space8. Taller buildings on same footprint9. Smaller lobbies10. Fewer entrances11. Faster installation12. Reduced maintenance costsDOUBLE DECK INSTALLATIONS

Transfer FloorsMost tall and very tall buildings provide some means to travel between zones and stacks. This is sometimes achieved by overlapping zones (Petronas Towers), introducing extra stops (Sears Tower) or shuttle lifts (World Trade Center). A common served floor (other than the Main Terminal or Sky Lobby) is important, where there are common facilities to be accessed, eg: restaurant, travel bureau, banking, sports facilities, post room, reprographics, etc.The effect on traffic handling can be disruptive. In general it is important to restrict access to such floors during up peak and down peak, although the purpose of such a floor would be defeated at other times, i.e.: at the mid day break or during interfloor traffic.

1.6 Top/Down ServiceA top/down lift installation is where a sky lobby is used to serve building zones or stacks both in the conventional up direction, but also in the down direction. This does mean that passengers may (psychologically) be concerned that they have travelled up a building only to be then required to travel down to their destination. This technique has only been applied in a few buildings.Vertical transportation Page 5 of 12 pagesThe concept is illustrated in Figure 1. This shows a low zone served from the Main Terminal floor at ground level. A sky lobby is positioned two thirds of the way up the building. From the sky lobby a conventional group of lifts serve the high above the sky lobby and another group serve the mid zone below the sky lobby. Although top/down is more expensive in equipment terms and may complicate the machine room and overtravel arrangements, the technique does allow a small footprint building to provide a larger rentable space.

(a) Double Deck Shuttles to Double Deck LocalsPetronas Towers, Kuala Lumpur, Malaysia (1996).The two Petronas Towers are 452 m high with 88 stories above ground. The building is divided into two stacks.Stack 1 has 2 groups of 6 double deck lifts serving Main Terminal and Floors 8-23 at 4 m/s and Main Terminal and Floors 23-37 at 5 m/s. Floor 23 acts as a transfer floor.Page 6 of 12 pages CIBSE National Technical Conference, 18 June 2002Stack 2 is served by a group of 5 double deck shuttle lifts at 6 m/s to sky lobbies at Floors 41/42. From the sky lobbies there are 3 groups of 6 double deck lifts serving 3 zones: Floors 44-61 at 3.5 m/s; Floors 61-73 7 m/s; Floors 61/62 and 69-83 at 7 m/s. Floors 61 and 62 act as transfer floors.There are 2 lifts linking Stack 1 to Stack 2 serving Floors 36-37, 40-43 at 1.6 m/s. There are escalators between the upper and lower Main Terminal (0/1) levels and between Floors 41 and 42.

Service Building

The Service Building is to the east of the Petronas Towers and contains the chiller plant system and the cooling towers to keep the Petronas Towers cool and comfortable.

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Presented By Deepika Dhilip Reg No:2014804005Thanking You

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