CODES

ADOPTS WITH AMENDMENTS:

International Building Code 2009 (IBC 2009)

Copyright

Effective Use of the International Building Code

Preface

Ordinance

Chapter 1 Scope and Administration

Chapter 2 Definitions

Chapter 3 Use and Occupancy Classification

Chapter 4 Special Detailed Requirements Based on Use and Occupancy

Chapter 5 General Building Heights and Areas

Chapter 6 Types of Construction

Chapter 7 Fire and Smoke Protection Features

Chapter 8 Interior Finishes

Chapter 9 Fire Protection Systems

Chapter 10 Means of Egress

Chapter 11 Accessibility

Chapter 12 Interior Environment

Chapter 13 Energy Efficiency

Chapter 14 Exterior Walls

Chapter 15 Roof Assemblies and Rooftop Structures

Chapter 16 Structural Design

Chapter 17 Structural Tests and Special Inspections

Chapter 18 Soils and Foundations

Chapter 19 Concrete

Chapter 20 Aluminum

Chapter 21 Masonry

Chapter 22 Steel

Chapter 23 Wood

Chapter 24 Glass and Glazing

Chapter 25 Gypsum Board and Plaster

Chapter 26 Plastic

Chapter 27 ElectricalEMERGENCY AND STANDBY POWER

Chapter 28 Mechanical Systems

Chapter 29 Plumbing Systems

Chapter 30 Elevators and Conveying Systems

Chapter 31 Special Construction

Chapter 32 Encroachments Into the Public Right-Of-Way

Chapter 33 Safeguards During Construction

Chapter 34 Existing Structures

Chapter 35 Referenced Standards

Chapter 36 DOCKS, PIERS, BULKHEADS AND WATERWAY STRUCTURES

Appendix A Employee Qualifications

Appendix B Board of Appeals

Appendix C Group U - Agricultural Buildings

Appendix D Fire Districts

Appendix E Supplementary Accessibility Requirements

Appendix F Rodentproofing

Appendix G Flood-Resistant Construction

Appendix H Signs

Appendix I Patio Covers

Appendix J Grading

Appendix K Administrative Provisions

3601.1 General

STATE AMENDMENT
The intent of this chapter is to provide minimum standards for the design, construction and maintenance of docks, piers, bulkheads, and waterway structures. The guidelines in this chapter address minimum standards for foundations, design forces, structural integrity, material selection and utilization and construction techniques.

3601.2 Scope

STATE AMENDMENT
The following structures shall be designed in accordance with the requirements of this chapter:
  1. Docks, piers, gangways, and catwalks, other than residential and farm docks and piers exempted from this chapter in the exceptions below, shall be designed by a registered design professional.
  2. All bulkheads having an exposed height greater than 5 feet or with a superimposed load shall be designed by a registered design professional and require special inspection. Special inspection shall be waived for bulkheads of any height constructed from property line to property line of one- or two-family dwellings and including attachment to neighboring bulkheads.
  3. Oceanfront retaining walls, bulkheads and other types of retaining walls used by the public on the coastline of the ocean or adjacent inlets shall be designed by a registered design professional.
  4. Marine terminal or port facilities for berthing, mooring, docking and servicing ships, barges, or tug boats that handle cargo of all types, including bulks, containers, liquids, fuels, and people, which shall be designed by a registered design professional in accordance with accepted industry standards.
  5. Groins not exempted below, jetties, breakwaters, oceanfront seawalls, and oceanfront revetments shall be designed by a registered design professional in accordance with accepted industry standards.
Exceptions: The following structures are exempt from the requirements of this chapter:
  1. Sill structures combined with marsh plantings and certain groins in accordance with the Department of Environmental and Natural Resources general permit requirements.
  2. Oceanfront and inlet sandbag revetments in accordance with the Department of Environmental and Natural Resources general permit requirements.
  3. Revetments constructed on single family residential property having a height no greater than 10 feet and slope greater than 1.5 horizontal: 1.0 vertical and in accordance with the Department of Environmental and Natural Resources general permit requirements.
  4. Farm structures not on public waters.
  5. Piers and docks associated with one- or two- family dwellings meeting the exceptions of the North Carolina Residential Code.

Section 3602 DEFINITIONS

STATE AMENDMENT
ADDITIVES. Substances added to a polymer resin or vinyl chloride material to aid in processing the material.

BOAT SLIP. A berthing place for one or two watercraft where the watercraft can be securely moored to cleats, piling, or other devices while the boats are in the water. Boat slips are commonly configured as “side-ties” or as single- or double-loaded “U” shaped berths.

BULKHEAD. A vertical wall structure designed to retain shoreline material and prevent erosion due to wave activity. CATWALK. A narrow footway platform extending alongside a structure.

DESIGN WAVE. A design wave that is potentially most damaging to an economically feasible structure, or wave for which a structure is designed.

DOCK. A structure extending alongshore or out from the shore into a body of water, usually accommodating multiple boat slips, to which boats may be moored in order to load or unload people or cargo.

EXTRUSION. Manufacturing process whereby a material is pushed through a die to form a shape of constant cross section. Vinyl Chloride sheet piling is generally manufactured using an extrusion process.

FETCH. Open water exposure over which waves are generated.

FIBER. One or more glass, carbon, or aramid filaments in the form of a continuous strand or roving in an FRP material.

FIBER ARCHITECTURE. Construction of a composite material from layers with different types and orientations of fibrous material.

FIBER ORIENTATION. Fiber orientation is the alignment of the longitudinal axis of a fiber in an FRP material with respect to the stated reference axis.

FIBER REINFORCED POLYMER (FRP). A composite material which consists of a polymer resin based matrix reinforced with fibers of glass, carbon, aramid, or hybrid combinations of these fiber types.

FIBER VOLUME FRACTION. The volume of reinforcement fiber in a cured composite divided by the volume of the composite section.

FILLER. Substance added to the matrix of a FRP material intended to alter its engineering properties, performance, or cost.

GANGWAY. A footway bridge extending from the dock, pier, bulkhead, or shore, usually to a floating structure.

GLASS TRANSITION TEMPERATURE (Tg). Temperature at which the polymer matrix of an FRP material changes from a glassy state to a rubbery state.

KING PILE. The primary structural member that supports horizontal panels to form a vertical wall sometimes used in bulkhead or groin construction.

LAMINA. A layer of fibers and resin in an FRP material.

MATERIAL LONGITUDINAL DIRECTION. Direction in an FRP material parallel to the direction of pultrusion (pulling) during the manufacture of a plate or structural shape.

MATERIAL TRANSVERSE DIRECTION. Direction in an FRP material orthogonal to the longitudinal direction.

MATRIX. Continuous constituent of an FRP material surrounding the reinforcing fibers and consisting of a polymer resin with any fillers and additives.

PIER. An elevated deck structure, usually pile supported, extending out into the water from the shore.

PILE. A timber, concrete, metal, or composite member embedded into the ground to support or brace a structure. “Piles” or “piling” are plural forms of “pile.”

PRIVATE WATERFRONT STRUCTURES. A dock, pier, bulkhead, or associated structure not open to the general public and with no more than ten total boat slips and no more than ten owners.

PUBLIC WATERFRONT STRUCTURES. A dock, pier, bulkhead, or associated structure located on multifamily residential property (greater than ten dwelling units), public property or commercial property.

PULTRUSION. Manufacturing process whereby a material is pulled through a die to form a shape of constant cross section. FRP plates and structural shapes are generally manufactured using a pultrusion process.

RESIN. An organic polymer possessing indefinite and often high molecular weight and a softening or melting range that exhibits a tendency to flow when subjected to stress.

REVETMENT. A sloping structure usually constructed of stone or concrete and placed on a shoreline to protect it against erosion by wave and current action.

ROVING. In an FRP material, a roving is a large number of continuous parallel filaments or a group of untwisted parallel strands.

SHEET PILE. A pile with a generally slender flat cross section to be embedded into the ground or seabed and meshed or interlocked with like members to form a diaphragm, wall, or bulkhead.

SYMMETRIC COMPOSITE. A symmetric composite is a composite material in which the sequence of lamina below the laminate mid-plane is a mirror image to those above the laminate mid-plane.

3603.1 General

STATE AMENDMENT
In addition to a building permit, permits may be required from federal, state, or county agencies such as the United States Army Corps of Engineers or the North Carolina Department of Environmental and Natural Resources. In cases of structures to be built on lakes operated by an electric utility for the generation of power, a permit from the operating utility may also be required.

3604.1 General

STATE AMENDMENT
Every structure shall be of sufficient strength to support the imposed dead, live, snow, wind, impact, and seismic loads without exceeding the prescribed stresses for the various materials described elsewhere in this code. Adequate consideration shall be made for forces imposed by earth, water, docking, and mooring.

3604.2 Dead loads

STATE AMENDMENT
The weight of the component parts of a structure shall be used in the design when it will influence the strength of the structural elements. All utilities, permanent furniture, dock boxes, and mooring hardware should be considered as dead load.

3604.3 Live loads

STATE AMENDMENT
Design live loads shall be the greatest load that will likely be imposed on the structure, including superimposed loads on retained material that exert horizontal loads on the structure. Where vehicles are allowed, actual weight of vehicles and wheel loads as specified in the latest edition of Standard Specifications for Highway Bridges of the American Association of State Highway and Transportation Officials or obtained from the vehicle manufacturer shall be used. The design load shall be posted at the dock or pier approach where vehicles are allowed. Minimum live loads are:
  1. Fixed piers, docks, catwalks - Private waterfront piers: 40 psf or 300 pounds concentrated load on any area 2 foot square. Public waterfront piers: Design loads shall be the greatest combinations of loads exerted on the structure but not less than 60 psf.
  2. Floating docks - Private waterfront docks: 20 psf, public waterfront docks: 30 psf, or 300 pounds concentrated load on any area 2 feet square. Under dead and live load, all floating docks shall have a minimum of 3 inches freeboard from the top of the flotation device, other than low freeboard watercraft (e.g. kayak) launching facilities. All floating docks subject to this chapter shall have not more than 5 degrees tilt from the horizontal under uniform live loading on one-half of the dock width or under concentrated load of 400 pounds applied within 12 inches of any side.
  3. Gangways - Gangways shall be designed for a live load of 100 psf. Flotation for gangway landing shall be designed for 50 psf, live load.
  4. Bulkheads, revetments - Design loads shall be the greatest combinations of loads exerted on the structure. Consideration shall be given to horizontal loads exerted by superimposed loads on the retained earth and by inclined surface slopes. Superimposed loads shall be considered when exceeding 50 psf and located within a horizontal distance of three times the height of the bulkhead from the face of the bulkhead.

3604.4 Snow loads

STATE AMENDMENT
Design snow loads shall be as prescribed in Chapter 16.

3604.5 Wind loads

STATE AMENDMENT
Design wind loads shall be as prescribed in Chapter 16 without moored vessels. In wind regions with a design wind speed greater than 90 mph, the design wind speed shall be no less than 90 mph (3 second gust). This gust wind speed shall be adjusted for duration and height (not restricted to 15 feet minimum) for wind pressures applied to vessels moored at the facility in accordance with Chapter 16.

3604.6 Impact loads

STATE AMENDMENT
Design impact loads shall be as prescribed in Chapter 16 but not less than 1.25 times the kinetic energy exerted by a striking vessel or vehicle.

3604.7 Seismic loads

STATE AMENDMENT
Design seismic loads shall be as prescribed in Chapter 16. Seismic loads are not applicable for any structure exempted from design by a registered design professional.

3604.8 Water loads

STATE AMENDMENT
Hydrostatic and hydrodynamic loadings shall be considered as follows:
Hydrostatic pressures shall be considered in conjunction with the equivalent fluid pressure of soil and any surcharge acting on the structure. For bulkheads, hydrostatic pressures shall be estimated based on maximum difference between retained and offshore water surface elevations.

3604.8.2 Current loads

STATE AMENDMENT
Current loads for structures and vessels shall be determined from records on current velocity using accepted engineering practice.
Sufficient anchorage against uplift between all components, except elements specifically designed to break away, shall be provided. Resisting forces shall be not less than 1.5 times the applied uplift force.

3604.8.4 Wave forces

STATE AMENDMENT
Wave forces shall be determined from wave records where available. Where no wave records are available, the design wave shall be determined from probable wind speed, direction, fetch, and water depth that will yield a critical wave. Forces shall then be calculated using accepted engineering practice.
All piers and floating docks shall be designed for water loading generated by wind and passing vessels. Adjacent to federal designated channels, water loading shall be based on commercial and recreational vessels with minimum passing speeds of 10 and 20 knots, respectively.

3604.9 Earth loads

STATE AMENDMENT
Lateral earth pressures shall be determined by considering the specific soil properties and applying earth pressure theories generally accepted for soil mechanics in engineering practice. A geotechnical investigation or other adequate consideration shall be given by the registered design professional for the effect of probable varying levels of retained water, tide, and flood water. Pressures exerted by the earth shall be checked for dry, moist, and saturated conditions as applicable.

3604.10 Erosion

STATE AMENDMENT
The effects of reasonably predictable erosion, propeller wash-induced scour, and wave-induced scour shall be given ample consideration.

3604.11 Water levels

STATE AMENDMENT
The ability to accommodate dead, live, wind, current, and wave loadings for the range of water levels (from low water to base flood level) anticipated at the site shall be given consideration. For public and private floating docks, guide piling systems shall be capable of accommodating water levels extending a minimum of 2 feet above base flood elevation plus the freeboard of the dock structure.

Section 3605 MATERIALS

STATE AMENDMENT

3605.1 General

STATE AMENDMENT
The quality of materials and fasteners used for load-supporting purposes shall conform to acceptable engineering practice.
Materials used for piling and repairing piling shall comply with applicable provisions of Chapter 18 and the material requirements of Sections 3605.3 through 3605.7.

3605.2.1 Helical anchors

STATE AMENDMENT
Helical anchors shall be hot-dip galvanized. A representative number of helical anchors subjected to tensile loading shall be load tested in accordance with ASTM D 3689 to two times their design load capacity. Load testing of anchors in tension shall include creep testing of a representative number of the anchors. Helical anchors shall be designed and installed as determined by a registered design professional.

3605.3 Wood

STATE AMENDMENT
Wood shall be pressure treated with a preservative recommended by the American Wood Preservers’ Association for the specific application. Wood species, preservative treatment, minimum lumber size, and lumber grade shall be in accordance with Table 3605.3. Handrails, guardrails, wallcaps, and decking may be constructed of naturally durable species where located above the normal high water mark.

TABLE 3605.3
SPECIFICATONS FOR SOUTHERN PINE2 LUMBER IN FRESH AND SALT WATER SERVICE
LOCATION COMPONENT AWPA USE CATEGORY1, 4 DIMENSIONS LUMBER GRADE MOISTURE CONTENT AT TREATMENT
Saltwater Freshwater Saltwater Freshwater
Above normal high water Decking3 3B 3B 54
2″ Nominal Min.
Premium No. 2 Premium No. 2 Surfaced dry 19%
Guardrails 3B 3B 2″ Nominal Min. No. 2 No. 2 Surfaced dry 19%
Wallcaps 3B 3B 2″ Nominal Min No. 2 No. 2 Surfaced dry 19%
Walers 3B 3B 4 x 6 Nominal No. 2 No. 2 KD 20% or less or dry 23%
Cross bracing 3B 3B 2″ to 4″ Nominal No. 2 No. 2 Surfaced dry 19%
Splash zone Split pile caps 4B 4B 2″ to 4″ Nominal No. 2 No. 2 Surfaced dry 19%
Stringers 4B 4B 2″ Nominal No. 2 No. 2 Surfaced dry 19%
Below normal high water Sheet piles 5B 4C 2″ to 4″ Nominal Marine No. 17 No. 2 Surfaced dry 19%
Walers 5B 4C 4 x 6 Nominal Marine No. 17 No. 2 KD 20% or less or dry 23%
Cross bracing 5B 4C 2″ to 4″ Nominal Marine No. 17 No. 2 Surfaced dry 19%
Rectangular timber piles Not Allowed6 4C 6 x 6 Nominal Not allowed6 No. 2 KD 20% or less or dry 23%
Round timber piles 5B6 4C ASTM D 25 ASTM D 25 ASTM D 25 25% or less
Engineered lumber Glulam timber 5B 4B 4″ Nominal Min. Note 5 Note 5 12% average
Parallel strand lumber 5B 4B 3½″ Nominal 1.8E or better 1.8E or better Per manufacturer's specifications
  1. Lumber shall be pressure treated with preservative treatment in accordance with AWPA U1.
  2. At the discretion of the building official, lumber species other than Southern Pine may be approved when span tables for wet use conditions are submitted, and the lumber is treated for comparable service life to the treatment specifications required by Table 3605.1.
  3. Wood composite decking, treated or untreated, shall provide equivalent service life to the treated decking specified in Table 3605.1.
  4. All notches, holes, and field cuts shall be field treated in accordance with AWPA M4.
  5. Glulam grade shall be specified as a layup combination or stress class in accordance with the National Design Specification or the manufacturer’s published data. Layup combinations shall consist of species and grades capable of the treatment retentions equivalent to the AWPA use categories specified in Table 3605.1.
  6. Commercial pile wraps may be used to extend the life expectancy of timber piles exposed to marine borers.
  7. AWPA requirements for Marine No. 1 specify that no heartwood be exposed on any face prior to preservative treatment.

3605.3.1 Wood connections

STATE AMENDMENT
All steel bolts, rods, and other hardware shall be hot-dip galvanized or protected with an equivalent system. All bolts, rods and other metal materials shall be no smaller than ⅝ inch in diameter. Beams, girders, or pile caps shall be attached to the piling with a minimum of two ⅝-inch hot-dip galvanized steel bolts per beam member through bolted at each piling connection. Piling shall not be notched so that the cross-section is reduced below 50 percent. Threaded fasteners shall not be tightened directly against wood surfaces but used only in conjunction with standard ogee or flat washers. Cold formed metal connectors shall not be used in wet applications or applications subject to wetting and drying cycles. Mooring hardware, including cleats, and pile guides shall be through bolted using sizes recommended by the manufacturer.

3605.4 Concrete

STATE AMENDMENT
Concrete components shall comply with applicable provisions of Chapter 19 and ACI 318. Minimum concrete strength, air entrainment, maximum chloride content, and maximum water cement ratio shall be determined from ACI 318 on the basis of required structural strength, required resistance to freeze-thaw exposure, required abrasion resistance, and required resistance to water penetration and salt water intrusion. Minimum concrete cover shall be increased and reinforcing steel spacing shall be decreased in accordance with ACI 350, to reduce crack size. All steel embedments, other than reinforcing steel, shall be stainless, hot-dip galvanized, or coated for corrosion protection. Field welds and abrasions of coatings on embeds shall be touch coated in the field.

3605.5 Structural steel

STATE AMENDMENT
Steel components shall comply with applicable provisions of Chapter 22 and AISC 360. All structural steel members, fasteners, and fittings shall be protected from corrosion by coating or cathodic protection for the specific exposure. Steel bulkhead components and dock components shall be hot-dip galvanized or coated to achieve the corrosion protection required for the degree of exposure of corrosive elements. Field welds and abrasions to coatings shall be touch coated after erection or installation is completed. Cold formed metal joists, girders, columns, and studs shall not be used in applications where the members are constantly wet or subject to wetting and drying cycles.

3605.6 Aluminum

STATE AMENDMENT
Aluminum bulkhead sheets or aluminum bulkhead or dock components shall be of proper alloy to resist corrosive elements in the adjacent water and soil. Bulkhead components and hardware shall be aluminum or stainless steel. Aluminum shall be galvanically and physically isolated from concrete and galvanically isolated from steel. Connection hardware and fasteners for aluminum components may be stainless steel or galvanized steel if isolated from aluminum structural elements.
Bulkheads, structural shapes, plates, and guardrail systems manufactured from vinyl chloride based materials or fiber reinforced polymer (FRP) materials shall be designed to comply with manufacturer’s published load tables or manufacturer’s published mechanical properties subject to the requirements for specific materials in Sections 3605.7.1, 3605.7.2, and 3605.7.3. Plastic and composite members shall contain additives to inhibit ultraviolet radiation degradation or shall be protected from ultraviolet radiation by an approved coating.
Vinyl chloride materials for sheet piling shall be specified and tested for conformance in accordance with ASTM D4216, including weathering tests in accordance with ASTM D1435. Mechanical properties shall be established in accordance with the tests specified in Table 3605.7.1. Design values of the tabulated properties shall conform to the limiting values specified in the table. The manufacturer of the sheet piling shall produce a certificate of analysis from a third party testing agency certifying the vinyl chloride material from which the sheet piling is manufactured conforms to the physical properties specified. The third party testing agency shall be accredited in accordance with ISO 17025 to conduct the specified tests. Testing programs shall address changes in material sources and composition over time, and test data shall accurately represent the properties of the product produced at any given time.

TABLE 3605.7.1
LIMITATIONS ON MECHANICAL PROPERTIES FOR VINYL CHLORIDE BASED SHEET PILING
MECHANICAL PROPERTY TEST PROTOCOL LIMITATIONS ON PROPERTY
Notch impact resistance ASTM D 256 2.0 ft-lb./in minimum
Drop dart impact resistance, Procedure A ASTM D 4226 1.0 in-lb./mil minimum
Drop dart impact resistance, Procedure B ASTM D 4226 2.0 in-lb./mil minimum
Tensile strength ASTM D 638 6,500 psi minimum
Modulus of elasticity in tension ASTM D 638 377,000 psi minimum
Deflection temperature under 264 psi ASTM D 648 158 psi minimum
Linear coefficient of expansion ASTM D 696 4.4 x 10-3 in/in/°F maximum
Deflection of vinyl sheet pile bulkheads shall not exceed the lesser of 160 times the height from the mud line to the top of the wall or 2 inches. Effects of in-service temperatures exceeding 80°F on modulus of elasticity shall be considered in deflection calculations and selection of materials.
Service load stresses in the vinyl sheet piling shall not exceed 3,200 psi.
Vinyl chloride based materials shall be compounded with stabilizing agents. Addition of stabilizers during the extrusion process is prohibited.
Vinyl sheet pile bulkheads shall have sufficient impact resistance, determined in accordance with ASTM D 256 and ASTM D 4226, to resist impact from vessels traveling at mooring speeds, resist wave impact when installed in high velocity flood zones (V-Zones on Flood Insurance Rate Maps), and to resist impact from debris likely to collide with the bulkhead at flood stage or in areas subject to storm surge.
Vinyl materials shall be tested for the in-service thickness in accordance with ASTM D 635 with a resulting burning rate of 2½ inches per minute or less.
Mechanical properties for FRP structural components shall be established in accordance with the tests specified in Table 3605.7.2. Each manufacturer shall publish the characteristic values for the product in accordance with ASTM D 7290. The manufacturer of the FRP shall produce a certificate of analysis certifying the FRP material and constituent materials from which the FRP components are manufactured conform to the physical properties specified. Testing programs shall address changes in material sources and composition over time, and test data shall accurately represent the properties of the product produced at any given time. Manufactured components shall be inspected in the plant in accordance with ASTM D 3917 for dimensional tolerances and according to ASTM D 4385 for visual defects. Inspection reports shall be provided.

TABLE 3605.7.2
LIMITATIONS ON PHYSICAL AND MECHANICAL PROPERTIES FOR FIBER REINFORCED POLYMER COMPONENTS1
PROPERTY ASTM TEST METHOD MINIMUM NUMBER OF TESTS
Barcol hardness D 2583 5
Glass transition temperature Tg D 4065 5
Coefficient of thermal expansion D 696 5
Moisture equilibrium content D 570 5
Longitudinal tensile strength D 638 10
Transverse tensile strength D 638 10
Longitudinal tensile modulus D 638 10
Transverse tensile modulus D 638 10
Longitudinal compressive strength D 6641 10
Transverse compressive strength D 6641 10
Longitudinal compressive modulus D 6641 10
Transverse compressive modulus D 6641 10
Longitudinal flexural strength D 790 10
Transverse flexural strength D 790 10
Longitudinal flexural modulus D 790 10
Transverse flexural modulus D 790 10
In-plane shear strength D 5379 10
In-plane shear modulus D 5379 10
Inter-laminar shear strength D 2344 10
Longitudinal pin bearingstrength D 9532 10
Transverse pin beariang strength D 9532 10
Pull through strength per fastner
t = ⅜″
t = ½″
t = ¾″
D 7332, Proc. B 10
  1. Property requirements for shapes apply to sheet piles.
  2. Tests shall be conducted for material thicknesses, t, tabulated and bolt sizes from ⅜ inch to 1 inch in diameter. No more than one third of the bolt shank within the thickness of the connection material may be threaded. Bolts shall be installed snug tight.
Service temperature of FRP structural components shall not exceed Tg-40°F, where Tg is the glass transition temperature determined in accordance with ASTM D 4065.
Fibers and matrix constituents shall comply with the following requirements:

3605.7.2.2.1 Fiber type

STATE AMENDMENT
Fibers shall be glass, carbon, aramid, or hybrid combinations of these fiber types. Glass fibers shall conform to ASTM D 578.
The fiber architecture of any pultruded element comprising the cross section of a pultruded FRP structural member shall be symmetrical and balanced. Each pultruded FRP structural element shall contain a minimum total fiber volume fraction of 30 percent.
Each element of a pultruded FRP structural member shall have fibers oriented in a minimum of two directions separated by a minimum of 30 degrees. In the direction of the longitudinal axis of the member, the percentage of continuous fiber in each pultruded element shall be a minimum of 30 percent of the total fiber reinforcement by volume for shapes and a minimum of 25 percent of the total fiber reinforcement by volume for plates. When multiple elements share a common edge in the direction of pultrusion, at least 50 percent of the nonroving reinforcement in the element having the largest percentage of nonroving reinforcement shall extend through the junction connecting the elements.
Determined in accordance with ASTM D 7290, the characteristic value of the tensile strength of the fiber strands, yarns, and rovings shall be at least 290,000 psi. Tensile tests shall be conducted in accordance with ASTM D 2343.

3605.7.2.2.5 Resin

STATE AMENDMENT
A commercial grade thermoset resin shall be used for fabricating pultruded FRP structural members.
Additives to the resin system that influence processing or curing, such as fillers, promoter, accelerators, inhibitors, UV-resistant agent, and pigments shall be compatible with the fiber and resin system.
Materials for FRP structural components shall be selected, designed, and manufactured to tolerate long-term environmental effects anticipated during the service life of the structure.
The following factors shall be considered in selecting FRP materials for marine structures:
  1. Performance criteria for the structure;
  2. Intended service life of the structure;
  3. Expected environmental conditions, including likelihood of exposure to alkalis or organic solvents;
  4. Protective measures; and
  5. Feasibility of maintenance and repair during service.
Unless the glass transition temperature determined in accordance with ASTM D 4065 and the tensile strength of the composite in the longitudinal and transverse directions determined in accordance with ASTM D 638 can be shown to retain at least 85 percent of their characteristic values after conditioning in the environments listed below, the nominal strength and stiffness shall be reduced for design purposes in accordance with test data produced from testing simulating the anticipated environment. Materials that cannot retain at least 15 percent of their characteristic values after conditioning the listed environments are prohibited in structural applications. Design tensile strength shall be reduced in accordance with material specific tests when in-service temperatures exceed of 90°F. Condition test samples as follows:
  1. Water: Samples shall be immersed in distilled water having a temperature of 100 ± 30°F and tested after 1,000 hours of exposure.
  2. Alternating ultraviolet light and condensing humidity: samples shall be exposed according to Cycle No. 1 (0.89 W/m2/mm, 8 hours UV at 60°C, 4 hours condensation at 50°C) using UVA-340 lamps in an apparatus meeting the requirements of ASTM G 154. Samples shall be tested within two hours after removal from the apparatus.
FRP sheet pile bulkheads shall have sufficient impact resistance, determined in accordance with ASTM D7136, for the intended application.
Deflection of vinyl sheet pile bulkheads shall not exceed the lesser of 160 times the height from the mud line to the top of the wall or 2 inches. Effects of in-service temperatures in excess of 90°F on modulus of elasticity shall be considered in deflection calculations.
FRP materials shall be tested for the in-service thickness in accordance with ASTM D 635 with a resulting burning rate of 2½ inches per minute or less.
Carbon fiber reinforced plate and wrap used for flexural and shear reinforcement of existing concrete structures shall be designed in accordance with the design procedures specified in ACI 440.2R. Mechanical properties of carbon fiber reinforced plate and wrap shall be established in accordance with the tests specified in ACI 440.3R.

3605.8 Masonry

STATE AMENDMENT
Masonry used in bulkheads and dock work shall comply with Chapter 21.

3606.1 Fixed piers

STATE AMENDMENT
Fixed piers shall be constructed in accordance with Sections 3606.1.1 through 3606.1.4.
Fixed piers shall be supported by pilings with tip penetrations dependent on the soil conditions and the total applied load. Piers support by shallow piling, legs or columns with point bearing on rock shall have provisions to resist horizontal forces and overturning, as well as flotation uplift. Piles shall be installed in accordance with the requirements of Chapter 18 and inspected in accordance with the requirements of Chapter 17.
Structural steel members shall be designed in accordance with AISC 360, Chapter 22 of this code, and the material requirements of this chapter. Concrete members shall be designed in accordance with ACI 318, Chapter 19 of this code, and the materials requirements of this chapter.

3606.1.3 Size of wood piles

STATE AMENDMENT
Piles shall be sized in accordance with the American Wood Council National Design Specification. In no case shall round timber piles be less than 7 inches in diameter at the butt and have a minimum tip diameter of less than 5½ inches. Rectangular timber piles shall not be less than nominal 6 inches by 6 inches.
Where required by design, bracing shall be sized to limit stresses in the piles from lateral loads in accordance with the American Wood Council National Design Specification to prevent buckling.
Maximum spans for pier pile caps or girders and joists or stringers shall be determined in accordance with the American Wood Council National Design Specification considering the member to be subject to wet use.

3606.1.6 Connections

STATE AMENDMENT
Connections between piling or legs to pile caps, stringers, beams, bracing and deck shall have sufficient capacity to safely support all applied loads and provide transfer of load to adjoining members.

3606.1.7 Gangways

STATE AMENDMENT
On coastal waterways, the maximum slope permitted shall be 3:1 at 0.0 mean low water or above and 2½:1 below 0.0 mean low water. On lakes and other inland waters, the maximum slope shall be 3:1 not less than 90 percent of the time and 2½:1 not more than 10 percent of the time.

3606.2 Flotation units

STATE AMENDMENT
Flotation units shall be foam-filled encapsulated floats or polystyrene billets securely wrapped with Class I woven geotextile fabric in accordance with AASHTO M288. The use of metal barrels not specifically designed for use as flotation devices and unwrapped polystyrene billets are prohibited.

3606.3 Electrical service

STATE AMENDMENT
All electrical service to marine structures shall be in accordance with the North Carolina Electrical Code.

3606.4 Fire protection

STATE AMENDMENT
All fire protection for marine structures shall be in accordance with applicable provisions of the North Carolina Fire Prevention Code.

3606.5 Fuel docks

STATE AMENDMENT
Fuel docks and other marine facilities handling flammable liquids shall comply with the Flammable and Combustible Liquids Code, NFPA 30 and the North Carolina Fire Prevention Code. All fuel installations shall be designed to prevent fuel spillage from entering the water. The fuel docks or floats shall be isolated to the extent that fire or explosion would have minimal opportunity to spread to or from the fuel dock to the berths. Storage tanks for public facilities shall be located a minimum distance of 50 feet from the dispenser with a shutoff valve at the tank.

3606.6 Guardrails

STATE AMENDMENT
For walkways, access piers, steps, or ramps, guardrails or other safety provisions shall be provided along the edges where the vertical drop to the lesser of the mean low water level, normal low water level (sounds), normal pool (lakes and rivers), or mud line exceeds 6 feet. Edges having a primary function other than walks or access ways, such as docking frontage and swimming access shall not require guardrails. Guardrails shall be designed in accordance with Chapter 16 for balconies. Guardrails shall be a minimum of 42 inches high and shall prevent the passage of a 21-inch sphere except where required otherwise by Chapter 11. Edge protection shall be provided as required by other rules.

Exception: For private waterfront piers and docks, guardrails or other safety provisions shall be provided along the edges where the vertical drop to the lesser of the mean low water level, normal low water level (sounds), normal pool (lakes and rivers), or mud line exceeds 8 feet. Guardrails shall be a minimum of 36 inches high and shall prevent the passage of a 21-inch sphere. Edge protection shall be provided as required by other rules.

3606.7 Accessibility

STATE AMENDMENT
Piers, docks, catwalks, gangways, and floating docks shall comply with Chapter 11 and ANSI/ICC A117.1 for accessibility.

3606.8 Egress

STATE AMENDMENT
Piers and docks shall be provided with means of egress in accordance with Sections 3606.8.1 through 3606.8.4.

3606.8.1 Occupant load

STATE AMENDMENT
Occupant load for piers and docks shall be calculated as follows:
Occupant load for piers and boardwalks intended for recreational fishing shall be calculated based on 3 linear feet of rail per person on the perimeter plus 50 square feet per person on a net area with a perimeter 3 feet inside the rail. Occupant load for piers and boardwalks intended for other uses shall be in accordance with Chapter 10.
Occupant load for docks constructed at public marinas intended for mooring of private pleasure craft shall be calculated based on 30 square feet of net dock area per person.
Occupant load for private waterfront docks shall be calculated based on 20 square feet per person.

3606.8.2 Piers

STATE AMENDMENT
Piers intended for recreational fishing, assembly, or educational purposes with travel distance to exit discharge exceeding 600 feet and greater than 15 feet above mean low water shall have emergency access ladders at 300 feet intervals and at the end of the pier. The pier shall be constructed of noncombustible material with the exception that the floor decking may be heavy timber.
Public waterfront docks intended for mooring of private pleasure craft with travel distance to exit discharge in excess of 600 feet shall have a second means of egress or a means of rescue from the water. Construction for these docks shall be noncombustible, with the exception that wood walers may be embedded in the dock edges for attachment of mooring hardware.
Buildings constructed on public waterfront piers and docks shall comply with the requirements of all applicable provisions of the North Carolina State Building Code.

3607.1 Bulkheads

STATE AMENDMENT
Bulkheads shall be constructed in accordance with Sections 3607.1.1 through 3607.1.5.

3607.1.1 General

STATE AMENDMENT
Bulkheads shall be constructed in a manner to be effective against erosion and provide for bank stabilization. The bulkhead system may consist of any of the following or combinations thereof: braced sheet pile walls with tie backs, king piles, and horizontal panels, gravity walls, cantilever and counterfort retaining walls. Bulkhead walls shall be constructed to prevent passage of fine material (See ASTM D 2487) through joints or cracks from the fill side to the stream side.

3607.1.2 Systems

STATE AMENDMENT
Local site conditions and performance of bulkheads in service shall govern in selection of a system. The potential for erosion and scour at the mud line shall also be investigated, and compensating features shall be reflected in the construction. Bulkheads shall be terminated by either tying into adjoining structures or by extending the bulkhead line a minimum of 10 feet in a landward direction at an angle of not less than 45 degrees to the shoreline in order to protect against end erosion or flanking by wave action. No structure shall be terminated without regard for end anchorage and stabilization.

3607.1.3 Guardrails

STATE AMENDMENT
Where designated public walkways, steps, or ramps run adjacent to bulkheads within 6 feet, guardrails or other safety provisions shall be provided along the top of the wall where the vertical drop to the lesser of the mean low water level, normal low water level (sounds), normal pool (lakes and rivers), or mud line exceeds 6 feet. Guardrails shall be designed in accordance with Chapter 16 for balcony guardrails. Guardrails shall be 42 inches high and shall prevent the passage of a 21-inch sphere except where required otherwise by Chapter 11. Edge protection shall be provided as required by other rules.

Exception: For private waterfront bulkheads with designated walkways within 6 feet, guardrails or other safety provisions shall be provided along the edges where the vertical drop to the lesser of the mean low water level, normal low water level (sounds), normal pool (lakes and rivers), or mud line exceeds 8 feet. Guardrails shall be a minimum of 36 inches high and shall prevent the passage of a 21-inch sphere. A wall cap 30 inches or less in width shall not be considered a designated walkway unless it is connected to a walkway. Edge protection shall be provided as required by other rules.

3607.1.4 Wood construction

STATE AMENDMENT
For wood grades, member sizes, preservative treatment, and protection of metal fasteners and fittings, see Section 3605.3.
Vinyl, fiber reinforced polymer, aluminum, concrete, and steel bulkheads shall be constructed in a manner to ensure performance. Connections shall be designed to resist the full applied load. For materials and corrosion protection reference Sections 3605.4 through 3605.7.

3607.2 Revetments

STATE AMENDMENT
Revetments shall be constructed in accordance with Sections 3607.2.1 through 3607.2.2

3607.2.1 Rigid revetments

STATE AMENDMENT
Rigid revetments shall be founded on a firm foundation to prevent undermining and progressive instability. Provisions shall be made to provide for toe protection to compensate for known or anticipated scour. Additional protection may be needed in active areas and may consist of sheet piling along the toe or stone rip rap. A pattern of weep holes shall be provided in the face to relieve hydrostatic pressure behind the wall. Joints shall be sealed or provided with a properly designed filter to prevent loss of fines from the protected slope.
Adequate provisions shall be made to prevent migration of fine materials through the structure. The face shall not be steeper than one unit horizontal to one unit vertical. Flatter slopes may be needed for stability depending on the construction materials and site conditions. The face may consist of armor stone, rip rap, or individual interlocking concrete units or poured concrete. Toe protection provisions shall be provided as discussed for the rigid type and the top of slope shall be detailed to prevent erosions under the revetment from surface water runoff. Flexible revetments shall be provided with a filter layer designed to prevent loss of fines from the protected slope and to relieve hydrostatic pressure behind the face.
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