MATERIALS STEEL RAILING Nuts and bolts not designated as high strength shall conform to the requirements of ASTM A 307, and steel tubing shall conform to the requirements of ASTM A 500.
Trang 1OTHER WORK ITEMS OF BRIDGE
Trang 2TABLE OF CONTENTS
I RAILINGS
II BRIDGE BEARINGS
III WATERPROOFING
IV EXPANSION JOINTS
V BRIDGE DRAINAGE
Trang 3I. RAILINGS
1. MATERIALS
STEEL RAILING
Nuts and bolts not designated as high strength shall conform to the requirements of ASTM A 307, and steel tubing shall conform to the requirements of ASTM A 500
ALUMINIUM RAILING
For aluminium railings or portions of railings, cast aluminium posts shall conform to the requirements of AASHTO M 193, and extruded components shall conform to the requirements of ASTM B 221M
WELDING
All exposed welds shall be finished by grinding or filing to give a smooth surface Welding of aluminium materials shall be done by an inert gas shielded, electric arc welding process using no welding flux Torch or flame cutting of aluminium will not be permitted
2. INSTALLATION
Metal railings shall be carefully adjusted prior to fixing in place to ensure proper matching at abutting joints, correct alignment, and camber throughout their length Holes for field connections shall be drilled with the railing in place on the structure at proper grade and alignment
Unless otherwise specified in the Contract Document, installation tolerance for railing height shall be -10 to +20 mm
All bolts and nuts shall be point welded
to each other
Where aluminium alloys come in contact with other metals or concrete, the contacting surfaces shall be thoroughly coated with a dielectric aluminium-impregnated caulking compound, or a synthetic rubber gasket may be placed between the two surfaces
II. BRIDGE BEARINGS
1 MATERIAL REQUIREMENTS
REFERENCE STANDARDS
AASHTO Standard Specifications for Highway Bridges and the following Standards in their latest edition shall be particularly applied
to the works covered by this Specification Section
ASTM A36 Carbon Structural Steel ASTM A123 Zinc (Hot-Dip Galvanized) Coating on Iron and
Steel Products ASTM A570 Steel, Sheet and Strip, Carbon, Hot-Rolled, Structural Quality
Billet-Steel Bars for Concrete Reinforcement
ASTM C881 Epoxy-Resin-Base Bonding Systems for Concrete
Trang 4ASTM C1107 Installation of Load Bearing (Transverse and Axial)
Steel Studs and Related Accessories ASTM D412 Vulcanized Rubber and Thermoplastic
Rubbers and Thermoplastic Elastomer Tension ASTM D429 Rubber Property-Adhesion to Rigid Substrates ASTM D518 Standard Test Method for Rubber
Deterioration-Surface Cracking ASTM D573 Rubber - Deterioration in an Air Oven
ASTM D746 Brittleness Temperature of Plastics and
Elastomers by Impact ASTM D1149 Rubber Deterioration - Surface Ozone Cracking in a Chamber ASTM D2240 Rubber Property -Durometer Hardness
ASTM D3182 Materials, Equipment, and Procedures for
Mixing Standard Compounds and Preparing Standard Vulcanized Sheets
ASTM D3183 Preparation of Pieces for Test Purposes
from Products ASTM D3184 Evaluation of
NR (Natural Rubber) ASTM D3185 Evaluation of SBR (Styrene-Butadiene Rubber)
Including Mixtures with Oil ASTM D3186 Rubber-Evaluation of SBR (Styrene-Butadiene
Rubber) Mixed With Carbon Black or Carbon Black and Oil
ASTM D3187 Evaluation of NBR
(Acrylonitrile-Butadiene Rubber) ASTM D3188 Evaluation of IIR (Isobutene-Isoprene Rubber) ASTM D3189Evaluation of Solution BR (Poly-butadiene Rubber) ASTM D3190 Evaluation of Chloroprene Rubber (CR)
ASTM D3192 Carbon Black Evaluation in NR
(Natural Rubber) ASTM D3192 Carbon Black Evaluation in NR (Natural Rubber)
ASTM D4014 Plain and Steel-Laminated Elastomeric Bearings for
Bridges
SAE 1020 Specifications for Rolled Strip Specifications for
Finish and Gauge
2 ELASTOMERIC BEARINGS
2.1. ELASTOMERIC MATERIALS
The elastomeric materials of the compounds shall be either natural rubber or 100% virgin polychloroprene synthetic rubber meeting the requirements of Table.1 The properties of the elastomeric compounds shall be determined from test specimens complying with ASTM
Trang 5D3182 through D3190 inclusive and D3192 A variation of ± 10% in tensile strength and ultimate elongation under “physical properties” will be permitted when test specimens are cut from the finished product
2.2. INTERNAL STEEL LAMINATES
The internal steel laminates for the laminated elastomeric bearing pads shall be rolled carbon steel sheets complying with ASTM A 570
or ASTM A36
2.3. LAMINATED ELASTOMERIC BEARING PADS
Laminated elastomeric bearing pads shall be individually moulded to the required size Corners and edges may be rounded with a radius
at the corners not exceeding 9 mm and a radius at the edges not exceeding 6 mm All edges of the steel laminations shall be covered with not less than 4 mm and not more than 6 mm of elastomer
Requirements of Elastomeric Bearing Pads
Ultimate elongation, min.% 350 Heat Resistance
D573, 70 HR at
100°C Change in durometer hardness, max.points + 15
Change in tensile strength, max % - 15 Change in ultimate elongation, max
Compressive Set
Method B
Ozone D1149 100 pphm ozone in air by volume,
20% strain, 37.7 ºC 1C, 100 hours mounting Procedure D 518,
No Cracks
Trang 6Procedure A Adhesion Bond made during vulcanization 80% R(Z1) D429, A Bond Strength (per square cm) 2.8kg
D429, B Peel Strength (per cm of width) 7 kg
The dimensions of the elastomeric bearings shall be within the following listed tolerances:
Overall Vertical Rubber Dimension
Average total rubber thickness 32
Average total rubber thickness over
32 mm
-0, +6
mm Overall Horizontal Rubber Dimension
Thickness of individual layers of elastomer (60
Variation from a plane parallel to the theoretical surface
sides 6
mm Edge cover of embedded metallic laminate 4 mm
min
6 mm max
The rubber laminates shall be of uniform integral units, capable of being separated by mechanical means into separate, well-defined elastomeric layers The ultimate breakdown limit of the elastomeric bearing under compressive loading shall be not less than 140 kgs/cm2 In addition to the requirements of Table No 1, the stress-strain relationship of the finished elastomeric bearings at room temperature shall not exceed the following limitations
Trang 7Compression
Strain (Percent of total thickness of all
elastomer laminations
The Contractor shall furnish to the Engineer a certification by the manufacturer that the elastomer, in the elastomeric bearing pads to
be furnished conforms to all of the above requirements The certification shall be supported by a certified copy of the results of tests performed by the manufacturer upon samples of the elastomer
to be used in the pads
3 MECHANICAL BEARINGS
Bearings shall have surface protecting in accordance with requirements and procedures
noted under Specification section 07800
3.1. BEARING INSTALLATION
The bearings shall be clearly marked with their longitudinal and transverse axes, their type number and their intended locations in the Works
Unless otherwise approved by the Engineer bearing beds shall be
of non-shrink grout conforming to ASTM C1107, Grade A with compressive strength 50MPa, and should be proposed by the Contractor for approval by the Engineer Grout should have flow characteristics such that the volume of the bed or plinth is completely filled with homogeneous material when placed at the ambient temperatures, and having physical and chemical properties compatible with the adjoining surfaces Proposals for the thickness and type of bearing plinths and beds shall be submitted by the Contractor and approved by the Engineer in advance of bearing installation
Anchor bolts shall unless otherwise specified on the Drawings or otherwise approved by the Engineer conform to ASTM F1554 Grade
55 Anchor bolts shall be either threaded full length or equipped with
a satisfactory mechanical end anchorage Details for any mechanical end anchorage shall be included in the shop plans submittal for prior approval All nuts shall be ASTM A563 Heavy Hex Grade DH
Steel dowels shall be provided and installed in accordance with requirements and with accessories noted on the drawings Dowels shall be smooth plain billet-steel bars conforming to requirements of ASTM A615, 400 MPa and shall be zinc (hot-dip galvanized) in accordance with ASTM A123
Dowels may be cast-insitu as shown on the drawings or drilled and grouted with an approved epoxy compound If dowels are drilled and grouted:
holes shall provide at least 10 mm in diameter greater than the largest diameter of the dowel;
Trang 8 holes shall be thoroughly cleaned with compressed air and
water prior to grouting of dowels so as to remove all loose or extraneous materials;
the epoxy compound used shall be ASTM C881, Type IV or
approved equivalent and mixed and placed in accordance with manufacturer’s requirements
Bearings shall not be dismantled Any transit bolts, straps or other temporary fixing shall not be removed until the bearing is fixed in its final position and the structure immediately above the bearing is in place Care shall be taken to ensure that all transit bolts, straps or other temporary fixings are finally removed
All bearings shall be set horizontal in both directions and shall be positioned so that the inscribed longitudinal axis is parallel to the structure axis at the point of support, unless otherwise noted on the Drawings
Any devices such as steel packs used to hold bearings level whilst being fixed, must be removed so that the bearing seats only on its grout pad
Where pre-cast beams and segments are placed on elastomeric bearings, immediately prior to the placing of each beam and segment the top of the bearing shall be coated with a sufficient thickness of approved mortar to take up any irregularities between the surface of the beams and segment and the bearings
The installation location of bearings shall be accurately marked The area where the bearings will be seated shall be accurately levelled When arranging steel reinforcing at bearing locations, a template showing bearing stud bolt positions shall be used to prevent interference between bearing studs and steel reinforcing
The characteristics of all bearing shall be within the Manufacturer’s tolerances and to the following tolerances:
Alignment, maximum departure from required vertical or
horizontal plane:
Alignment, maximum departure from required vertical or
horizontal plane:
Lower part of bearing 1:1000 relative to upper
Plan position
Center/Center Spacing 3mm
Trang 93.2. TESTING OF BEARINGS
The testing of selected bearings shall be arranged with the Engineer prior to their inclusion in the Works The testing shall be done at an independent testing facility approved by the Engineer
III. WATERPROOFING
1 BITUMINOUS WATERPROOFING MEMBRANE
The Contractor shall furnish to the Engineer certification from the manufacturer that the bituminous waterproofing membrane system has been used successfully in similar applications during the preceding five years
The Contractor shall provide to the Engineer evidence that the applier of the material is a qualified, experienced applier and is approved by the manufacturer to apply his materials
Primer: The furnished primer material shall be in accordance with ASTM-D41, or as approved by the Engineer
Mastic: The furnished primer material shall be in accordance with AASHTO-M243, as applicable and as approved by the Engineer
Asphalt: Asphalt for mop coat shall be in accordance with ASTM D449, Type III Waterproofing fabric: Asphalt saturated fabric shall be in accordance with ASTM D173
Asphalt plank: Material for asphalt plank, if used or if approved by the Engineer, shall be in accordance with ASTM D517
2 PRODUCT DELIVERY, STORAGE AND HANDLING
The Contractor shall deliver products to the job site in their original unopened containers clearly labelled with the manufacturer’s name, brand designation, type and class as applicable
The Contractor shall store products in an approved dry area and shall protect them from contact with soil and from exposure to the elements Products shall be kept dry at all times
Products shall be handled in a manner that will prevent breakage of containers and damage to products
3 PREPARATION OF SURFACE
The surface to which the waterproofing is to be applied shall be cleaned of all loose and foreign materials, dirt, grease or oil and shall be dry When necessary the Engineer may require the surface
to be scrubbed with water and a stif brush, after which the surface shall be allowed to dry before application of the primer
Concrete to which the deck waterproofing membrane is to be applied shall be prepared in accordance with the manufacturer’s recommendations
4 APPLICATION
The deck waterproofing membrane shall be a proprietary waterproofing system as approved by the Engineer, and shall be
Trang 10applied in accordance with the manufacturer’s recommendations The installation shall be undertaken by skilled operatives as approved by the product manufacturer Acceptance testing shall include testing by
an electronic pinhole detector to demonstrate the absence of pinholes
IV. EXPANSION JOINTS
1 REFERENCE STANDARDS
The following Standards in their latest edition shall be particularly applied to the works covered by this Specification Section
AASHTO M297 Preformed polychloroprene elastomeric joint
seals for Bridges ASTM A36 Standard Specification for General Requirements for Rolled
Structural Steel Bars, Plates, Shapes, and Sheet Piling
ASTM A240 Heat-Resisting Chromium and Chromium-Nickel
Stainless Steel Plate, Sheet, and Strip for Pressure Vessels
JIS G 5502 Spheroidal Graphite Iron Castings
ASTM A123 Zinc (Hot-Dip Galvanized) Coatings on Iron and
Steel Products ASTM A588High-Strength Low-Alloy Structural Steel 50ksi Minimum Yield point
Rubbersand Thermoplastic Elastomer
- Tension
ASTM D994 Preformed Expansion Joint Filler for Concrete
(Bituminous Type) ASTM D1149 Rubber Deterioration - Surface Ozone Cracking
in a Chamber ASTM D2240 Rubber Property - Durometer Hardness
ASTM D4070 Adhesive Lubricant for Installation of Preformed
Elastomeric Bridge Compression Seals in Concrete Structures
ASTM D5973 Elastomeric Strip Seals with Steel Locking Edge
Rails Used in Expansion Joint Sealing ASTM D6690 Joint and Crack Sealants, Hot Applied, for
Concrete and Asphalt Pavements MATERIALS
2 METHOD OF CONSTRUCTION AND INSTALLATION
The Contractor shall obtain installation instructions from the supplier
of the expansion joint material and comply with the instructions provided for the installation of the joint The adequacy of the joint