Iranian Classification Society Rules

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Section 1 Definitions and Design Documentation


101. Definitions


1. Recurrence Period

The recurrence period is a specified period of time which is used to establish design values of ran- dom parameters such as wave height.

2. Operator

An operator is any person or organization empowered to conduct operations on behalf of the Owners of an installation.

3. Constructor

A constructor is any person or organization having the responsibility to perform any or all of the following.

(A) Fabrication

(B) Erection

(C) Inspection

(D) Testing

(E) Load-out

(F) Transportation and installation

4. Platform Structures

(1) Various types of offshore structures to which these Rules may be applied are defined below.

(A) Pile Supported Platform

This type of structure is characterized by slender foundation elements, or piles, driven into the sea floor.

(B) Gravity Structure

This type of structure rests directly on the sea floor. The geometry and weight of the struc- ture are selected to mobilize the available cohesive and frictional strength components of the sea floor soil to resist loadings.

(C) Compliant tower

This type of structure has narrower and more flexible tower than the typical pile supported platform and is supported by piles.

(D) Articulated Buoyant Tower

This type of structure depends on buoyancy acting near the water surface to provide the

necessary righting stability.

(2) Additionally, these Rules may be employed, as applicable, in the classification of structural types not mentioned above (1) when they are to be used as permanent offshore installations.


102. Design Documentation


1. General

The design documentation to be submitted is to include the reports, calculations, plans, and other documentation necessary to verify the structural design.

2. Design Documentation

The contents of reports are to comply with the recommended list of items given below.

(1) Environmental Consideration

(A) Reports on environmental considerations are to describe all environmental phenomena appro-

priate to the areas of construction, transportation, and installation. The types of environ- mental phenomena to be accounted for, as appropriate to the type and location of the struc- ture are as follows.

(a) Wind

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(b) Waves

(c)

Current

(d) Temperature

(e)

(f)

Tide

Marine growth

(g) Chemical components of air and water

(h) Snow and ice

(i)

(j)

Earthquake

Other pertinent phenomena

(B) The establishment of the environmental parameters is to be based on appropriate original da- ta or, when permitted, data from analogous areas. Demonstrably valid statistical models to extrapolate to long-term values are to be employed, and any calculations required to estab- lish the pertinent environmental parameter should be submitted.

(C) Preferably, a report on the various environmental considerations is to present data and con- clusions on the relevant environmental phenomena. The report is, however, required to sepa-

rately present a summary showing the parameters necessary to define the Design

Environmental Condition and Operating Environmental conditions. Where applicable, the like- ly environmental conditions, such as strength and ductility level earthquake, are to be expe-

rienced during the transportation of the structure to its final site.

(D) The report on environmental considerations may also contain the calculations which quantify the effects of loadings on the structure where these are not provided in other documentation.

(2) Foundation Data

(A) A report on foundation data is to present the results of investigations or, when applicable, data from analogous area on geophysical, geological and geotechnical considerations existing at and near the platform site. The manner in which such data is established and the specific items to be assessed are to be in compliance with 702. The report is to contain a listing of references to cover the investigation, sampling, testing, and interpretive techniques employed during and after the site investigation.

(B) The report is to include a listing of the predicted soil-structure interaction, such as p-y data, to be used in design. As appropriate to the planned structure, the items which may be cov- ered are as follows.

(a)

Axial and lateral pile capacities and response characteristics

(b) The effects of cyclic loading on soil strength

(c)

Scour

(d) Settlements and lateral displacements

(e)

(f)

Dynamic interaction between soil and structure The capacity of pile groups

(g) Slope stability, bearing and lateral stability

(h) Soil reactions on the structure

(i)

Penetration resistance

(C) Recommendations relative to any special anticipated problem regarding installation are to be included in the report. Items such as the following are to be included in the report.

(a)

Hammer size

(b) Soil erosion during installation

(c)

Bottom preparation

(d) Procedures to be followed should pile installation procedures significantly deviate from those anticipated.

(3) Materials and welding

(A) Reports on structural materials and welding may be required for metallic structures, concrete structures or welding procedures where materials and procedures are used which do not con-

form to those provided for in Ch 3.

(B) For metallic structures, when it is intended to employ new alloys not defined by a recog- nized specification, reports are to be submitted indicating the adequacy of the material's met- allurgical properties, fracture toughness, yield and tensile strengths, and corrosion resistance, with respect to their intended application and service temperatures.

(C) For concrete structures, when it is not intended to test or define material properties in ac-

cordance with applicable standards of this Society, a report is to be provided indicating the standards actually to be employed and their relative adequacy with respect to the corre- sponding relative standards which are recognized by this Society.

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3. Calculation

(1) Calculations are to be submitted to verify the propriety of the planned design. These calcu- lations are to be made out by logical and general methods. For the Computerized input and output type of calculations, the examination report of the program, program manual and user's manual are to be submitted if necessary.

(2) Design and analysis calculations are to be submitted for items relating to loadings, structural

stresses and deflections for in-place and marine operations. In this regard, calculations are to be in general compliance with the items listed below.

(A) Loadings

Calculations for loadings are to be submitted in accordance with Sec 3.

(B) Structural stress and deflections

(a) The stress and deflection calculations to be submitted are to include, those required for nominal element or member stresses and deflections.

(b) As applicable, and where required in subsequent sections of these Rules, calculations may also be required for the stresses in localized areas and structural joints, the dynam-

ic response of the structure, and fatigue life of critical members and joints.

(c)

For pile supported structures, calculations for the stresses in piles and the load capacity of the connection between the structure and the pile are to be submitted.

(d) For gravity structures, calculations are to be submitted for the effects of the soil's re-

action on the structure.

(e)

When accounting for the stress resultants described above, and those resulting from con- sideration of marine operations(see Sec 9), calculations are to demonstrate the adequacy of the structural elements, members or local structure. Also, the calculations are to dem- onstrate, as applicable, that the deflections resulting from the applied loadings and over- all structural displacement and settlement do not impair the structural performance of the platform.

(C) Marine operation

As applicable, calculations are to be submitted in accordance with Sec 9.

(D) Other calculations

As required, additional calculations which demonstrate the adequacy of the overall design are to be submitted. Such calculations should include those performed in the design of the cor-

rosion protection system.


103. Plans and Other Data


1. General

Generally, structural plans and other data are to be submitted. These plans are to include the following.

(A) The plans including general specification of the installed site and the location of the

structure.

(B) Design criteria including recurrence period used for environmental phenomena evaluation

(C) General arrangement of the installation

(D) The manual of safety and protection device

(E) Number of persons who live in the structure

(F) The lists of authorized Governments for the structure

(G) The list of new characteristics

(H) The brief manual of monitoring device

(I) The manual for procedure of transportation and installation

2. Plans and Other Data

Plans which are to be submitted in relation to the design of structures are defined below.

(A) Arrangement plans, elevations, and plan views.

(B) Plan views clearly showing in sufficient detail the overall configuration, dimension and lay- out of the structure, its facilities and foundation in relation to above (A)

(C) Layout plans indicating the locations of equipment and locations of the equipment loads and other design deck loads, fender loads, etc., which are imposed on the structure

(D) Structural plans indicating the complete structural arrangement, dimensions, member sizes,

plating and framing, material properties, and details of connections and attachments; for con- crete structures, arrangements and descriptions of reinforcement procedures for construction

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are to be indicated

(E) Pile plans indicating arrangements, nominal sizes, thicknesses and penetration

(F) Welding details and procedures, and schedule of nondestructive testing

(G) Corrosion control systems

(H) Structural plans indicating the complete arrangements of structures, such as helideck, crane pedestals, equipment foundations and manner of reinforcement, fendering, various houses and other structures which are not normally considered vital to the overall structural integrity of the offshore structure

(I) Various information in support of novel features utilized in the offshore structure design,

such as hydrostatic and stability curves, elements of any mooring system, etc.