1. SCOPE
2. REFERENCES
3. DEFINITIONS
4. SUBGRADE AND SUB-BASE
4.1 Subgrade
4.2 Sub-base
5. ROADS AND PARKING AREAS
5.1 General
5.2 Width and Radii
5.3 Road Classification
5.4 Special Traffic
5.5 Pavement Support System
5.6 Road Elevations
5.7 Cross Slope
5.8 Degree of Curvature
5.9 Parking Areas
6. AREA SURFACING AND PAVING
6.1 General
6.2 Portland Cement Concrete Surfacing
6.3 Portland Cement Concrete Pavement Design
6.4 Asphalt Concrete Area Surfacing
6.5 Asphalt Pavement Design
7. UNDEVELOPED AREAS
8. MARL SURFACING
9. SURFACE DRAINAGE
10. CULVERTS AND PIPE CROSSING
Table I – Geometric and Surface Design Criteria
Table II – Plant Road Design Traffic – Operational Traffic Per Year
Table III – Plant Road Design Traffic – Construction Traffic
Design Criteria for Surfacing, Paving and Roadways
1. Scope
This article establishes the design criteria for surfacing, pavings, and roadways.
2. References
Reference is made in this standard to the following documents.
American Association of State Highway and Transportation Officials (AASHTO)
HB 13 Standard Specifications for Highway Bridges
M 147 Materials for Aggregates and Soil-Aggregates Sub-base, Base and Surface Courses
A Policy on Geometric Design of Highways and Streets
American Concrete Institute (ACI)
325.1R Design of Concrete Overlays for Pavements
325.9R Recommendations for Construction of Concrete Pavements and Concrete Bases
American Concrete Pavement Association (ACPA)
EB209P Thickness Design for Concrete Highway and Street Pavements (Metric)
IS061P Design and Construction of Joints for Concrete Streets
American Society for Testing and Materials (ASTM)
C 76/76M Specification for Reinforced Concrete Culvert, Storm Drain and Sewer Pipe
D 1196 Test Methods for Non-repetitive Static Plate Load Tests of Soils and Flexible Pavement Components, for Use in Evaluation and Design of Airport and Highway Pavements
D 1557 Test Method for Laboratory Compaction Characteristics of Soil Using Modified Effort (56,000 ft-lbf/ft3 (2,700 kN-m/m3))
D 1883 Test Method for CBR (California Bearing Ratio) of Laboratory-Compacted Soils
Asphalt Institute, U.S.A. (AI)
MS-1 Thickness Design
3. Definitions
For the purpose of understanding this standard, the following definitions apply.
Base. The asphalt concrete base course used in the pavement system to reinforce and protect the subgrade or sub-base.
Sub-base. The crushed aggregate layer used in the pavement system between the subgrade and the asphalt concrete base course or reinforced concrete pavings and roadways.
Subgrade. The prepared and compacted soil immediately below the sub-base.
Surfacing. The asphalt surface course (wearing course) laid on top of the asphalt concrete base course, or the reinforced concrete surface laid on top of the sub-base.
4. Subgrade and Sub-Base
4.1 Subgrade
4.1.1 The pavings and roadways shall be built on company approved subgrade and shall conform to SES C02-S01, paragraph 7.2.1.a and SES C02-S02, paragraph 7.2.1.
4.1.2 California Bearing Ratio (CBR) tests or plate load tests shall be performed in conformance with ASTM D 1883 and D 1196 respectively to determine the strength of subgrade. Asphalt paved roads shall be designed based on CBR test results, and concrete paved roads shall be designed based on plate load test results. The design CBR value and design modulus of subgrade reaction value shall be equal to or greater than 90 percent of test results. These values shall be obtained from Project Geotechnical Report.
4.2 Sub-base
Sub-base for pavings and roadways shall consist of clean, tough, durable, crushed aggregate, for example crushed stone and gravel, conforming to AASHTO M 147, Grade C. Sub-base shall be compacted to at least 95 percent of the maximum dry density obtained from ASTM D 1557, and shall have a minimum soaked CBR value of 70 percent. Sub-base shall be maintained in a damp condition, and within the specified density requirements, until the pavement is placed.
5. Roads and Parking Areas
5.1 General
Unless otherwise specified in project specification or on the design drawings, road and parking areas shall be paved with asphalt concrete, except in the following areas, where concrete pavement shall be provided:
a. Plant process equipment areas
b. Maintenance areas
c. Areas around buildings and access to the buildings as required
d. Loading and unloading areas as required
e. Areas where collection of storm water, firewater, or washdown is required
f. Areas of diked walls, as required
g. Parking areas subject to hydrocarbon spillage
h. Roads subject to spillage of petroleum or other solvent products on a regular basis, unless otherwise specified
5.2 Width and Radii
The width of plant roads and shoulders, and radii of intersections, shall be as shown in Table I.
5.3 Road Classification
Surfaced roads shall be classified according to the amount of use and traffic. The plant road design traffic is listed in Table II and III. The classifications are:
5.3.1 Plant Entrance Road. This road serves as the main plant entrance road and will have regular heavy truck and car traffic.
5.3.2 Primary Interplant Road. This road serves as a primary operational and maintenance road within the plant and will have regular truck and maintenance crane traffic and heavy axle loads.
5.3.3 Secondary Interplant Road. This road serves as an interplant operational and maintenance road and will have light vehicular traffic and light maintenance crane traffic. Heavy truck and maintenance crane traffic will be small except during plant turnarounds.
5.3.4 Service Road. This road serves tankage areas, bulk storage yards, and other areas away from the main facility. These will require only light maintenance traffic.
5.3.5 Access Way. This way provides access to equipment or facility areas from secondary interplant roads.
5.3.6 Perimeter Patrol Road. This road serves remote areas of the plant, for example security fence area.
5.4 Special Traffic
Special traffic areas shall be designed for transport trucks, cranes, special equipment, and forklift trucks, using manufacturer’s loading data for the equipment anticipated.
5.5 Pavement Support System
Pavement support system design shall be based on Project Geotechnical Report.
5.6 Road Elevations
5.6.1 Finished road elevations from design drawing shall be the crown elevation of the road, and shall be 300 mm above surrounding grade, unless otherwise indicated.
5.6.2 Unless otherwise shown on design drawings, gradients on roads within the boundary of the plant area shall be a minimum of 1:400 (0.25 percent). Accessways shall have maximum gradients of 1:20 (5 percent).
5.6.3 The crown elevation of the roads adjacent to, or encircling a building, shall be at least 150 mm lower than high point of the ground floor slab of the building.
5.7 Cross Slope
Asphalt paved, concrete paved or crushed aggregate roadways and shoulders shall have a minimum cross sectional slope of 1:50 (2 percent).
5.8 Degree of Curvature
The degree of curvature for horizontal curves relative to various design speeds shall be in accordance with AASHTO ‘A Policy on Geometric Design of Highways and Streets’.
5.9 Parking Areas
5.9.1 Parking areas shall be designed for automobiles and light truck traffic only. They shall be of same construction as secondary interplant roads.
5.9.2 Parking areas serving H10 or heavier trucks shall have a pavement structure equal to the road(s) serving the parking area.
6. Area Surfacing and Paving
6.1 General
6.1.1 Area surfacing and paving shall be specified by company on a unit by unit basis after the plot plans are developed.
6.1.2 Area surfacing shall include paving beneath and around the equipment, in storage, laydown and work areas.
6.2 Portland Cement Concrete Surfacing
This shall conform to 6.3.1, 6.3.2, 6.3.4 and 6.3.6 as a minimum. Additional requirements are specified in the appropriate paragraphs.
6.2.1 The minimum paving thickness for sidewalks, walkways and areas not subject to vehicular traffic shall be 100 mm.
6.2.2 Areas subject to vehicular traffic shall have a minimum paving thickness of 150 mm.
6.2.3 Heavy lift crane pad in process area and crane accessway over underground facilities that require protection, shall have a minimum thickness of 250 mm.
6.2.4 For heavy equipment, truck accessways, and truck loading areas, concrete pavements shall be designed in accordance with 6.3.
6.2.5 All edges of concrete pavement and pavement adjacent to manholes, or catch basins shall be thickened; the extent to be determined by the design engineer.
6.2.6 Pavement subject to chemical attack shall have an appropriate protective coating.
6.2.7 Pavement shall be curbed if containment of chemicals or hydrocarbons is required.
6.2.8 Sections of pavement within process areas shall be divided, to conform with fire zone area designations.
6.3 Portland Cement Concrete Pavement Design
6.3.1 The concrete materials, testing, proportioning and furnishing shall be in accordance with SES B51-S01. The reinforcement shall be welded steel wire fabric or steel reinforcement conforming to SES B51-S01.
6.3.2 Unless otherwise specified in project specification, the minimum compressive strength of structural concrete shall be 25 MPa at 28 days.
6.3.3 Thickness of concrete pavement for roadways and paving areas shall be designed in accordance with ACPA EB209P or ACI 325.1R, based on input from section 5 (for example estimated traffic volume and type) and modulus of subgrade reaction from Project Geotechnical Report. The thickness of crushed aggregate sub-base shall be a minimum of 100 mm for pavings and 150 mm for roadways, and in accordance with 4.2.
6.3.4 Reinforcement for Paving Areas. This shall meet the following requirements:
a. The minimum reinforcement area shall be equal to 0.15 percent of the pavement cross section area
b. The minimum clear cover from top of pavement shall be 40 mm for 100 mm thick pavement, and 50 mm for pavement thicker than 100 mm
c. Bar spacing shall be a maximum of 300 mm on centers, and welded wire fabric shall be a minimum of 150 mm x 150 mm grid
d. Where foundations protrude through the paving, 12 mm diameter rebar, 760 mm long, shall be placed diagonally at all interior corners of paving
6.3.5 Reinforcement for Roadways. This shall meet the following requirements:
a. Road may be either jointed and reinforced, or continuously reinforced
b. Reinforcement requirements shall be determined by the subgrade drag formula given inSES B53-E01, paragraph 10.1.2
c. The minimum clear cover from the top of the slab shall be 50 mm
d. The minimum reinforcement area shall be equal to 0.15 percent and 0.10 percent of the slab cross sectional area in the longitudinal and transverse directions respectively
6.3.6 Joints for Paving Areas. These shall meet the following requirements:
a. Joints details shall conform to ACPA IS061P
b. Joints shall be shown on the design drawings
c. Pavement shall have isolation joints with a minimum thickness of 12 mm at junctions with foundations, manholes, catch basins, ditches, roads, and walls
d. Pavement shall have contraction joints and expansion joints at a maximum spacing of 5 m and 10 m respectively.
e. Joints shall divide the pavement into squares or rectangular areas where practical. The maximum ratio of length to width of rectangular area shall be 2.
f. Reinforcement shall be discontinued at joints, but smooth dowel bars shall be provided at mid-depth of pavement having vehicular traffic. These bars shall be 460 mm long, and spaced at 300 mm. Dowel surfaces on one side of the joint shall be covered with grease, or other approved coating, to prevent bonding.
6.3.7 Joints for Roadways. These shall meet the following requirements:
a. Joint details shall conform to ACPA IS061P
b. Longitudinal construction joints between lanes and transverse construction joints shall have deformed steel tie bars and a continuous tooled or sawed recess for sealant. These tie bars’ cross sectional area shall be determined using the subgrade drag method (see 6.3.5.b) but shall be at least 12 mm diameter at 600 mm spacing.
c. Expansion joint and contraction joints shall be provided at the interval of not more than 25 m and 10 m respectively
d. The width of joints shall be 12 mm, and the top 25 mm of the joints shall be sealed with an oil resistant compound
6.3.8 Pavement Finish. Concrete roadways shall be given a broom finish. Process area pavement shall be given a woodfloat finish, which permit sweeping clean.
6.3.9 Construction of pavings and roadways shall be in accordance with SES C04-S01 and ACI 325.9R.
6.3.10 Design life shall be 20 years.
6.4 Asphalt Concrete Area Surfacing
Minimum surface thickness for areas surfaced with asphalt concrete shall be 50 mm. The asphalt concrete base course shall be designed in accordance with section 5 (for example estimated traffic volume and traffic type) and 6.5.
6.5 Asphalt Pavement Design
6.5.1 Materials for the asphalt concrete base and crushed aggregate sub-base shall conform to SES C04-S02. Thickness of asphalt concrete base and crushed aggregate sub-base shall be designed in accordance with AI MS-1, based on input from section 5 and the Subgrade Resilient Modulus from the Project Geotechnical Report.
6.5.2 Asphalt concrete base on sandy soil shall have a crushed aggregate sub-base.
6.5.3 Mean annual air temperature shall be obtained from project site data.
6.5.4 Design life shall be 20 years.
6.5.5 Construction of pavings and roadways shall be in accordance with SES C04-S02.
7. Undeveloped Areas
Undeveloped sand laden areas shall be stabilized with a 50 mm to 100 mm thick layer of graded gravel.
8. Marl Surfacing
Construction laydown areas, process plant rough graded sites, and utility-plant rough graded sites shall be surfaced with 300 mm of marl.
9. Surface Drainage
9.1 Roads shall be crowned for adequate drainage, see 5.6. Collected storm water shall be disposed of via ditches provided on both sides of the roads, where possible.
9.2 In paved areas where spills may occur, paving shall be sloped towards catch basins and manholes. Collected storm water shall be disposed of via sewer system for treatment, in accordance with SES C03-S01.
9.3 In paved areas where spills are not likely to occur, paving shall be sloped at a minimum of one (1) percent and a maximum of four (4) percent; outward draining to side ditches or catch basins. However, the maximum elevation change between high point of pavement (HPP) and low point of pavement (LPP) shall be 150 mm.
9.4 Low point of pavement (LPP) shall be at least 100 mm higher than the grade elevation.
9.5 Unpaved areas shall be sloped in accordance with design drawings.
10. Culverts and Pipe Crossing
10.1 Bridges and pipe culverts shall be of reinforced concrete construction, and shall be designed in accordance with AASHTO HB 13. The material shall conform to ASTM C 76/76M, Class IV. Coated corrugated metal pipe may be used. Minimum pipe or culvert shall be 300 mm for lengths up to 10 m, and 375 mm for lengths over 10 m.
10.2 Rectangular concrete curbs, 150 mm minimum height, shall be provided at the side of the bridge deck where a bridge crossing is made.
10.3 Heavy-duty guard railing shall be provided at the sides of roadways having culverts and pipe crossing, where warranted.
10.4 The bridge clear width shall be equal to the width of roadway plus shoulders. The width of bridge leading to the main entrance of the plant, shall be in accordance with RC Engineering Manual.
Table I – Geometric and Surface Design Criteria
(1) Minimum Width – Width may be adjusted to meet special conditions.
(2) Minimum inside radius of road at intersection may be adjusted to meet special conditions.
(3) AC (Asphalt Concrete), CONC (Concrete), ACBC (Asphalt Concrete Base Course), CA (Crushed Aggregate).
(4) Includes 2000 mm median.
(5) This information shall be provided on project specification or design drawing.
Table II – Plant Road Design Traffic – Operational Traffic Per Year
Table III – Plant Road Design Traffic – Construction Traffic
