標準號：ISO 19901-2-2004
中文標準名稱：石油和天然氣工業. 海上建筑物的特殊要求.第2部分:地震設計規程和標準
英文標準名稱：Petroleum and natural gas industries - Specific requirements for offshore structures - Part 2: Seismic design procedures and criteria
標準類型：E94
發布日期：1999/12/31 12:00:00
實施日期：1999/12/31 12:00:00
中國標準分類號：E94
國際標準分類號：75.180.10;91.120.25
適用范圍：This part of ISO 19901 contains requirements for defining the seismic design procedures and criteria foroffshore structures; guidance on the requirements is included in Annex A. The requirements are applicable tofixed steel structures and fixed concrete structures. The effects of seismic events on floating structures andpartially buoyant structures are also briefly discussed. The site-specific assessment of jack-ups in elevatedcondition is only covered in this part of ISO 19901 to the extent that the requirements are applicable.Only earthquake-induced ground motions are addressed in detail. Other geologically induced hazards such asliquefaction, slope instability, faults, tsunamis, mud volcanoes and shock waves are mentioned and brieflydiscussed.The requirements are intended to reduce risks to persons, the environment, and assets to the lowest levelsthat are reasonably practicable. This intent is achieved by using:a) seismic design procedures which are dependent on the platform's exposure level and the expectedintensity of seismic events;b) a two-level seismic design check in which the structure is designed to the ultimate limit state (ULS) forstrength and stiffness and then checked to abnormal environmental events or the accidental limit state(ALS) to ensure that it meets reserve strength and energy dissipation requirements.For high seismic areas and/or high exposure level fixed structures, a site-specific seismic hazard assessmentis required; for such cases, the procedures and requirements for a site-specific probabilistic seismic hazardanalysis (PSHA) are addressed. However, a thorough explanation of PSHA procedures is not included.Where a simplified design approach is allowed, worldwide offshore maps are included in Annex B that showthe intensity of ground shaking corresponding to a return period of 1 000 years. In such cases, these mapsmay be used with corresponding scale factors to determine appropriate seismic actions for the design of a structure.