Technical Specification_32m Guyed Mast

Grameenphone

32m Guy Supported Mast Technical Specifications

momenur.rahman

1

Introduction

1.1

Scope of the Work: This document outlines the requirements for supply a 32m Guyed Mast that will be used in a radio site to support its telecom ancillaries to ensure coverage of GSM networks.

1.2

Reference of work: All work performed and materials supplied within the scope of this specification shall comply in every respect to the following documents: 1. British Standard and Code of Practice. 2. Bangladesh National Building Code.

2

Design Criteria

1.3

Type of Tower: 3-legged/4-legged Guy supported steel Tower made of hot-rolled sections.

1.4

Land Size: Land size is variable; but limited to maximum 30x30 sq m. We prefer a 32m Guyed Mast on an 18x18 sq m land, but to ensure low-cost solution, designer may choose maximum 30x30 sq m piece of land if required to meet the expected steel weight mention in section 2.3.

1.5

Expected Weight of Guyed Mast: Total weight of steel frame must not be greater than 2.2 ton (without cable weight), if design is done considering angles. In case of using circular tube, equivalent weight must be considered to ensure low-cost solution.

1.6

Geometry of Guyed Mast: Tower Height: 32 Meter. Base Height of tower: 0 Meter. Dimension of tower: Width at top/Minimum Neck length/Width at base: No specific value. Designer may choose appropriate value to meet the requirements mentioned in section 2.9

1.7

Tower Design Code: BS8100 Part 1, 2, 3, &4

1.8

Design Wind Speed: 200km/hr fastest mile wind speed (i.e. 42.92 m/s average mean hourly wind speed with due allowance being made for fluctuating wind load due to Gust effects.) Partial Safety Factors for wind speed, Υv : 1.15 Partial Safety Factors for dead load, ΥDL

: 1.1 (when dead load effects increase wind load effects) : 0.9 (when dead load effects reduce wind load effects) Wind direction Factor, Kd or Sd : 1.0 (BS8100 Part 1&4) Terrain Category: Country (BS8100 Part 4) Distance from Sea: 100 km Structure is to be considered as Untested Class A structure. Partial Safety factor on design strength (both member and bolt), Υm : 1.1 1.9

Antenna Configuration: Antenna Configuration is Given below: GSM Antenna Configuration GSM

Length (m)

Nos

2.6m length

6

Ht (m) 30.7

MW Configuration MW

1.

Dia (m)

Nos

Ht (m)

1.2m dia

1

30

1.2m dia

1

28

Mounting point offsets shall be taken from standard antenna catalogue.

2. The antenna and ancillary configuration are on Antenna Configuration sheet.

3

Materials strength and others

1.10 Steelworks: For steel works BS 4360 & BS8100 will be followed 1.11 Materials: Angles: Grade S275 or S355 to BS EN 10025: 1993 Hot rolled products of non-alloy structural steel. Yield Stress fy = 275 or 355 MPa Circular Hollow Sections Grade S275 or S355 to BS EN 10210: 1994-1 Hot finished structural hollow sections of non-alloy structural steel. Yield stress fy = 275 or 355 MPa Bars Steel bar to BS4449:1978 Yield stress fy = 250 MPa (mild steel) or 460 MPa (hot rolled high yield) 1.12 Galvanization:

All relevant parts of the tower should be galvanized with thickness of 80-100 milli microns. BS729 can be followed if needed. 1.13 Welding: Welding will be according to BS 5135. 1.14 Bolts and Nuts: Anchor bolts and structural bolts used for legs and main bracing members shall be of Grade 8.8 with the following properties:Yield Strength. fy = 627 N/mm2 Ultimate tensile strength fu = 784 N/mm2 Shear Strength. fv = 375 N/mm2 All other bolts shall be of Grade 5.6 minimum. 1.15 Anchor Bolts: The anchor bolts will be designed as per reaction forces the designer finds appropriate for his tower. The designer has the choice to consider plain or deformed bar. To confirm unison of the submitted designs GP will determine the ultimate bolt dimensions. To give and idea about anchor bolts and their orientation, please see the bolt details provided below. 1.16 Work platform & Rest platform: Not required. 1.17 Ladders and hoops: Not required. But provision must be kept to ensure safe climbing. 1.18 Lightning Arrestor: A lightning arrestor of 16 mm dia and minimum 1 meter length will be provided at the top of the tower with the concept of providing complete protection to the antennas and ancillaries along with tower members below. The rod will be galvanized like the structural member of the tower. 1.19 Aviation/ Obstruct-ion Light: Aviation light consisting of components likes sensor, converter, LED and alarm. 1.20 Serviceability Requirement: Maximum rotation of the node where the antenna will be fixed shall not to exceed 0.5 degrees under operating wind speed 35.32 m/s. 1.21 Lead time: 45 days 1.22 Delivery: As per requirements of GrameenPhone, It could be Warehouse or any BTS.

1.23 Mode of Transport: Tower and tower related equipments should be transported to the destined site by the supplier's own responsibility. 1.24 After Sales Service: The supplier must give a warranty for the product sold/supplied for at least 5 (Five) years to 20 years from the date of supply / handover. The supplier must bear the responsibilities of providing agreed service after the sale of a specific product. The range, manner, validity and limit of after sale service is fixed in consultation with Procurement representative, the supplier and the user. 1.25 Spare: A list of spare parts for the machinery/product must be available in case for replacing any parts. The supplier is the concerned person to ensure the availability of such parts and should be ready to deliver whenever required, as agreed by all the parties.

4

Specification of Aviation Light (full system)

1.26 General Specifications: 1. Body: Copper free aluminum casting and all stainless steel latches & hardware for corrosion protection. 2. Paint: Paint should be highly weather and corrosion resistant 3. The light element should be mounted on glass epoxy PCB. 4. Protection: Bird spike, Ice protection, Gasket for weather proofing, IP 65. 5. It should be omni-directional which should meet the ICAO and FAA regulations. 6. It should have easy connection facility with quality connector 7. The aviation light should have the alarm generation option so that in case of any failure of maximum (more than 50%) LED (Default setup) the alarm can be generated automatically from the aviation system through potential free contact point. 8. LED should be connected in series and parallel combination. It should be in multiple numbers. It is required to avoid any series failure should not cause total black out. (In case of any single LED failure not more than 30 LED will be affected i.e., not more than 30 LED should be connected in series). Also at least 10 parallel stripes should be integrated. 9. It can be single unit or set of units like Light, controller, power unit etc. 10. It should have good quality day night sensor. It should not cause any false alarm during day time. (Light should be off during day time). 1. There should be minimum requirement of cabling. 1.27 Technical specification: 1. Type: LED 2. Color: RED 3. Intensity of light: > 30 Lumen

4. Working voltage: DC 40 – 60 Volt, (rated 54Vdc), Built in fuse protection without any alarm in this operating voltage range. All LED should glow within this range. 5. MTBF: > 50,000 hrs 6. Alarm: Through PFC 7. Sensor: Day and night sensor 8. Mountable: Tower mountable 9. Temperature: 0cC to 55oC for continuous operation. 10. (Max. 80oC for short time). 1.28 Others feature: (optional) Supplier can add more feature to en hence the product quality and life. Control unit can be single for up to three lights or individual for each light.

5

Lightning Arrestor A lightning arrestor is a 16 mm diameter rod of 1500 mm length with sufficient provision of fixing at tower top. The lightning arrestor will be fixed on tower top in a position just above the wave guides so that it does not impede climbing of a climber to the top of the tower.

6

Design and Analysis

1.29 Tower: The tower design shall be prepared using MS Tower Version 5. MS Tower is verified, commercially available, comprehensive 3D structural engineering software with a direct emphasis on telecommunication tower design and analysis. Detailed printouts shall be attached to the report inclusive of input and output files. The wind load is applied to the tower in a full 360 degrees. 1.30 Guy and accessories: Guy and all its accessories shall be designed as per BS8100 Part 4. Detailed calculation must be submitted with sufficient details for better understanding of the user.

7

Report and Calculation Layout 1. All calculations must be compiled in the following order and must be endorsed by a professional engineer. 2. Calculations submitted shall be sufficiently detailed for an independent appraisal to be carried out when required. 3. All calculations shall be submitted in hard and soft copy, in the original format. All relevant input and output MS Tower files shall be provided in soft copy.

1.31 Towers: The report shall contain but not limited to, information in the following format.

1. Introduction 2. Assumptions 3. Design Parameters 4. The design standards and codes of practice. 5. Derivation of wind resistance and drag coefficient shall be clearly stated 6. Loading (Dead Load, Antenna Load, Imposed Load and Wind Load) 7. Summary of Tower Analysis 8. Summary on Tower Stability 9. Summary on Tower Design 10. Summary on Tower Deflection The above report shall also include an appendices section which shall contain an appropriate method of analysis, depending upon the structure type, which shall be explicitly stated for compliance. 1. Equivalent static method 2. Non-linear analysis The appendices deliverables shall contain the following items: 1. Detailed Structural Analysis Calculations 2. Detailed Wind Load Calculations 3. Detailed Member Capacity Calculation 4. Detailed Design of Joints 5. Detailed Design of Base Plate and Holding Down Bolts For Towers 1.32 Guy and Accessories: All relevant documents and calculations must be submitted for all accessories that are recommended to be used by the designer.