DEPARTMENT OF ARCHITECTURE ABUBAKAR TAFAWA BALEWA UNIVERSITY, BAUCHI ARC 624: ADVANCED BUILDING SERVICES LESSON 2: CONVEYANCE SYSTEMS IN BUILDINGS

Transcription

1 DEPARTMENT OF ARCHITECTURE ABUBAKAR TAFAWA BALEWA UNIVERSITY, BAUCHI ARC 624: ADVANCED BUILDING SERVICES LESSON 2: CONVEYANCE SYSTEMS IN BUILDINGS 2.1 Introduction Definitions 2.1 Introduction 2.2 Conveyance systems in buildings 2.3 Lifts (elevators) 2.4 Escalators 2.5 Moving sidewalks 2.6 References Conveyance An elevator, dumbwaiter, escalator, moving sidewalk, platform lift or stairway chairlift. Elevator One of the following devices: A hoisting and lowering mechanism, equipped with a car that moves within guides and serves two or more landings to transport material or passengers or both. An escalator??? A dumbwaiter A moving walk??? An inclined stairway chairlift An inclined or vertical wheelchair lift Dumbwaiter A hoisting and lowering mechanism equipped with a car of limited size which moves in guide rails and serves two or more landings that is used exclusively for carrying materials Escalator Power-driven, inclined, continuous stairway used for raising or lowering passengers. Moving walk A type of passenger-carrying device on which passengers stand or walk, and in which the passenger-carrying surface remains parallel to its direction of motion and is uninterrupted. 1

2 Inclined elevator An elevator that travels at an angle of inclination of 70 degrees or less from the horizontal. Stairway chairlift A device used to transport physically handicapped persons over architectural barriers. Wheelchair lift A device used to transport wheelchair handicapped persons over architectural barriers. Hoistway An opening through a building or structure for the travel of elevators, dumbwaiters, or material lifts, extending from the pit floor to the roof or floor above. Elevator pit The portion of a hoistway extending from the sill level of the bottom terminal landing to the floor at the bottom of the hoistway. Emergency brake A mechanical device independent of the braking system used to retard or stop an elevator should the car over-speed or move in an unintended manner. 2

3 2.2 Conveyance systems in buildings The purpose of conveyance systems in buildings is to move people and objects across buildings either vertically or horizontally. There are two types of conveyance stems: Conveyance systems within buildings (elevators, dumbwaiters, escalators, moving sidewalks, platform lifts and stairway chairlifts). Conveyance systems between buildings (skywalks) 2.3 Lifts (elevators) A lift (or elevator) is a form of vertical transportation between building floors, levels or decks, commonly used in offices, public buildings and other types of multi-storey accommodation. Lifts can be essential for providing vertical circulation, particularly in tall buildings, for wheelchair and other non-ambulant building users and for the vertical transportation of goods. Some lifts may also be used for firefighting and evacuation purposes. There are several different types of lift, including: Hydraulic lifts An above ground or in-ground piston is used for raising and lowering under hydraulic pressure. Hydraulic lifts are generally only suitable in buildings of up to 8 storeys. 3

4 Traction lifts Electrically-powered cable-operated lifts driven by steel ropes rolled over a pulley and balanced by a counterweight (often a second lift moving in the opposite direction). 4

5 Roped hydraulics or hybrid lifts These are lifts that use both ropes and hydraulic power. Climbing lifts These include their means of propulsion, rather than being pulled or pushed from elsewhere. Scenic Lifts Lifts that include glass panels, and are within a shaft that includes glass panels, or are not within a shaft, sometimes on the outside of buildings. Capsule Lifts Lifts within a glass enclosure. In very tall buildings, sky lobbies may be provided, which are intermediate floors allowing passengers to transfer from an express lift that only stops at the sky lobby, to another lift that serves storeys above the lobby. An evacuation lift is a lift installation that is appropriately sited and protected and that contains a number of safety features that are intended to ensure that the lift remains usable for evacuation purposes during a fire. A firefighting lift is a lift designed to have additional protection, with controls that enable it to be used under the direct control of the fire and rescue service in fighting a fire. A firefighting lift is required if the building has a floor more than 18m above, or more than 10m below fire service vehicle access level. Firefighting lifts have very specific safety requirements and the presence of firefighting controls within a lift does not necessarily mean that it is a firefighting lift Construction of hoistways and hoistway enclosures 5

6 2.3.2 Fire-Resistive Construction Partitions between hoistways and machine rooms having fire-resistive enclosures shall be of non-combustible solid or openwork construction. Openwork construction shall reject a ball 25 mm in diameter, except where there are openings essential for ropes, drums, sheaves, and other elevator equipment. Hoistway enclosure openings shall be protected with entrances or access doors having a fire protection rating conforming to the requirements of the building code Non-Fire-Resistive Construction The hoistway shall be fully enclosed Enclosures and doors shall be unperforated to a height of 2 m above each floor or landing and above the treads of adjacent stairways. Openwork enclosures, where used above the 2 m level, shall reject a ball 25 mm in diameter Enclosures shall be permitted to be glass, provided it is laminated glass Partially Enclosed Hoistways For elevators that are not fully enclosed, protection at least m high shall be provided on the hoistway sides that are located 1.5 m or less from elevator equipment to areas accessible to other than elevator personnel Pits A pit shall be provided for every elevator. The floor of the pit shall be approximately level Permanent provisions shall be made to prevent accumulation of ground water in the pit Drains and sump pumps, where provided, shall comply with the applicable plumbing code, and they shall be provided with a positive means to prevent water, gases, and odours from entering the hoistway. Sumps and sump pumps in pits, where provided, shall be covered. The cover shall be secured and level with the pit floor. Safe and convenient access shall be provided to all pits. Access shall be by means of the lowest hoistway door or by means of a separate pit access door. There shall be installed in the pit of each elevator, where the pit extends more than 900 mm below the sill of the pit access door, a fixed vertical ladder of non-combustible material, located within reach of the access door. Pits shall be accessible only to elevator personnel. A permanent lighting fixture shall be provided in pits. The pit depth shall be not less than is required for the installation of the buffers, compensating sheaves, if any, and all other elevator equipment located therein and to provide the minimum bottom car clearance and runby. 6

7 Where the distance from the pit floor to the underside of the plank channels or slings exceeds 2100 mm (83 in.), with the car at the lowest landing, a means shall be permanently installed or permanently stored in the pit to provide access to the equipment on the underside of the car Location of Counterweights Counterweights shall be located in the hoistway of the elevator that they serve, or in a remote hoistway subject to the limitations and requirements of relevant codes Refuge Space on Top of Car Enclosure An unobstructed horizontal area of not less than 0.5 m2 shall be provided on top of the car enclosure for refuge space. It shall measure not less than 600 mm on any side. This area shall be permitted to include the space utilized for the top emergency exit. The minimum vertical distance in the refuge area between the top of the car enclosure and the overhead structure or other obstruction shall be not less than 1.1 m when the car has reached its maximum upward movement Enclosure of Machine Rooms and Machinery Spaces Machines, control equipment, sheaves, and other machinery shall not be exposed to the weather Fire-Resistive Construction of Machine Rooms and Machinery Spaces Spaces containing machines, control equipment, sheaves, and other machinery shall be separated from the remainder of the building by a fire resistive enclosure conforming to the requirements of the building code. Openings in the machine room enclosure shall be protected with access doors having a fire protection rating conforming to the requirements of the building code Machine Rooms and Machinery Spaces A permanent and unobstructed means of access to elevator machine rooms and overhead machinery spaces shall be provided. Only machinery and equipment used in conjunction with the function or use of the elevator shall be permitted in the elevator machine room. A clear path of not less than 450 mm shall be provided to all components that require maintenance. A clearance of not less than 450 mm (18 in.) shall be provided in the direction(s) required for maintenance access. Permanent electric lighting shall be provided in all machine rooms and machinery spaces. Machine rooms shall be provided with natural or mechanical means to keep the ambient air temperature and humidity in the range specified by the elevator equipment manufacturer to ensure safe and normal operation of the elevator. 7

8 Elevator machine and control rooms shall not be located in the hoistway Beams, Supports and Foundations Machines, machinery, and sheaves shall be so supported and maintained in place as to prevent any part from becoming loose or displaced under the conditions imposed in service. Supporting beams, if used, shall be of steel or reinforced concrete. The foundation shall support the total weight of the machine, sheaves, and other equipment, and the floor, if any. 2.4 Escalators Floor openings for escalators shall be protected against the passage of flame, heat, and/or smoke in accordance with the provisions of the applicable building code The angle of inclination shall be designed not to exceed 30 degrees from the horizontal, but due to field conditions at the site shall be permitted to exceed this maximum by 1 degree. The angle shall be measured at the centreline of the steps. The width of the escalator shall be the width of the step tread. The handrail shall be a minimum of 100 mm horizontally and 25 mm vertically away from adjacent surfaces. Balustrades shall be installed on each side of the escalator. Each balustrade shall be provided with a handrail moving in the same direction and at substantially the same speed as the steps. Hand or finger guards shall be provided at a point where the handrail enters the balustrade. Step frames, treads, risers, and dynamic skirt panels, excluding the step's attachments or inserts, shall be metal, except that magnesium alloys shall not be used. The depth of any step tread in the direction of travel shall be not less than 400 mm, and the rise between treads shall be not more than 220 mm. Each escalator driving machine shall be provided with an electrically released and mechanically or magnetically applied brake. Lighting of Escalator. Landing floor plates and all exposed step treads shall be illuminated with a lighting intensity of not less than 50 Iux. 2.5 Moving Walks Floor openings for moving walks shall be protected against the passage of flame, heat, and/or smoke in accordance with the provisions of the applicable building code. The sides and undersides of the moving walk truss or group of adjacent trusses in a single well way shall be enclosed in materials defined as either non-combustible or limited-combustible by the building code The angle of inclination from the horizontal shall not exceed 3 degrees within 900 mm (36 in.) of the entrance and egress ends and shall not exceed 12 degrees at any point. The height of the balustrade shall be not less than 900 mm nor more than 1 m from the tread way to the top of handrail, measured perpendicular to the tread way surface. 8

9 The handrail shall be a minimum of 100 mm horizontally and 25 mm vertically away from adjacent surfaces Balustrades shall be installed on each side of the moving walk. The balustrade on the tread side shall have no areas or mouldings depressed or raised more than 6.4 mm from the parent surface. Such areas or mouldings shall have all boundary edges bevelled or rounded. Each balustrade shall be provided with a handrail moving in the same direction and at substantially the same speed as the tread way. Hand or finger guards shall be provided at points where the handrails enter the balustrade. 2.6 Building Codes for Lifts There are a number of British Standards that apply to lifts: BS EN 81: Safety rules for construction and installation of lifts. BS 5588: Fire precautions in the design, construction and use of buildings. BS 7594: Code of practice for audio-frequency induction-loop systems (AFILS). BS 8300: Design of buildings and their approaches to meet the needs of disabled people code of practice. 2.7 References 9