Effects of Sea Water Level Fluctuations on Seismic Response of Jacket Type Offshore Platforms
To understand the seismic behavior of the offshore
structures, the dynamic interaction of the water-structure-soil should
be assessed. In this regard the role of the water dynamic properties in
magnifying or reducing of the effects of earthquake induced motions
on offshore structures haven't been investigated in precise manner in
available literature. In this paper the sea water level fluctuations
effects on the seismic behavior of a sample of offshore structures has
been investigated by emphasizing on the water-structure interaction
phenomenon. For this purpose a two dimensional finite element
model of offshore structures as well as surrounded water has been
developed using ANSYS software. The effect of soil interaction with
embedded pile foundation has been imposed by using a series of
nonlinear springs in horizontal and vertical directions in soil-piles
contact points. In the model, the earthquake induced motions have
been applied on springs and consequently the motions propagated
upward to the structure and surrounded water. As a result of
numerical study, the horizontal deformations of the offshore deck as
well as internal force and buckling coefficient in structural elements
have been recorded and controlled with and without water presence.
In part of study a parametric study has been accomplished on sea
water level fluctuations and effect of this parameter has been studied
on the aforementioned numerical results.
[1] K.J. Venkataramana, and K. Kawano, "Nonlinear dynamics of offshore
structures under sea wave and earthquake forces", Sadhana, parts 2-4,
1995,pp 501-512, India
[2] J. Penzien , M. K. Kaul, B. Berge, "Stochastic response of offshore
towers to random sea waves and strong motion earthquakes", Computer
Structures Jr,1972, pp. 733-756.
[3] R.G. Bea, "Earthquake and wave design criteria for offshore platforms".
J. Struct. Div, Am. Soc.,Civ. Eng., 1979, 105(ST2): 401-419.
[4] S. A. Anagnostopoulos, "Wave and earthquake response of offshore
structures: Evaluation of modal solutions", J. Struct. Div., Am. Soc. Cir.
Eng., 1982, 108(ST10): 2175-2191.
[5] Technical Drawing, "SPD10, BS10 & FSP10 Platforms Field Layout,
Drawing No. Sp9/10-PO-IL-D-9640, National Iranian Oil Company
[6] H.J. Bungartz, M. Schäfer, "Fluid-structure Interaction: Modeling,
Simulation, Optimization", Springer-Verlag, 2006, ISBN 3-540-34595-
7.
[7] H. Matlock, "Correlations for design of laterally loaded piles in soft
clay", Proc. 2nd Annual Offshore Technology Conference, 1970, pp.
577-594.
[8] K. Kayvani, F. Barzegar, "Modeling of Tubular Members in Offshore
Steel Jackets under Severe Cyclic Loading", UNICIV Report No. R-324,
School of Civil Engineering, The University of New South Wales,
December 1993, ISBN No. 858412918.
[9] V.A. Zayas, E.P. Popov, and S.A. Mahin, "Cyclic inelastic buckling of
tubular steel Braces", Report No. UCB/EERC-80/16, Earthquake
Engineering Research Center, University of California, Berkeley, CA,
1980.
[10] Release 11.0 Documentation for ANSYS, Copyright ┬® 1995-2002.
[11] A. K. Chopra, "Earthquake Response Analysis of Concrete Dams
.Advanced Dam Engineering for Design, Construction and
Rehabilitation", Von Nostrand Reinhold, 1988.
[12] American Petroleum Institute, Recommended practice for planning,
designing and constructing fixed offshore platforms. API Recommended
Practice 2A (RP -2A). 21st ed, 2000.
[1] K.J. Venkataramana, and K. Kawano, "Nonlinear dynamics of offshore
structures under sea wave and earthquake forces", Sadhana, parts 2-4,
1995,pp 501-512, India
[2] J. Penzien , M. K. Kaul, B. Berge, "Stochastic response of offshore
towers to random sea waves and strong motion earthquakes", Computer
Structures Jr,1972, pp. 733-756.
[3] R.G. Bea, "Earthquake and wave design criteria for offshore platforms".
J. Struct. Div, Am. Soc.,Civ. Eng., 1979, 105(ST2): 401-419.
[4] S. A. Anagnostopoulos, "Wave and earthquake response of offshore
structures: Evaluation of modal solutions", J. Struct. Div., Am. Soc. Cir.
Eng., 1982, 108(ST10): 2175-2191.
[5] Technical Drawing, "SPD10, BS10 & FSP10 Platforms Field Layout,
Drawing No. Sp9/10-PO-IL-D-9640, National Iranian Oil Company
[6] H.J. Bungartz, M. Schäfer, "Fluid-structure Interaction: Modeling,
Simulation, Optimization", Springer-Verlag, 2006, ISBN 3-540-34595-
7.
[7] H. Matlock, "Correlations for design of laterally loaded piles in soft
clay", Proc. 2nd Annual Offshore Technology Conference, 1970, pp.
577-594.
[8] K. Kayvani, F. Barzegar, "Modeling of Tubular Members in Offshore
Steel Jackets under Severe Cyclic Loading", UNICIV Report No. R-324,
School of Civil Engineering, The University of New South Wales,
December 1993, ISBN No. 858412918.
[9] V.A. Zayas, E.P. Popov, and S.A. Mahin, "Cyclic inelastic buckling of
tubular steel Braces", Report No. UCB/EERC-80/16, Earthquake
Engineering Research Center, University of California, Berkeley, CA,
1980.
[10] Release 11.0 Documentation for ANSYS, Copyright ┬® 1995-2002.
[11] A. K. Chopra, "Earthquake Response Analysis of Concrete Dams
.Advanced Dam Engineering for Design, Construction and
Rehabilitation", Von Nostrand Reinhold, 1988.
[12] American Petroleum Institute, Recommended practice for planning,
designing and constructing fixed offshore platforms. API Recommended
Practice 2A (RP -2A). 21st ed, 2000.
@article{"International Journal of Architectural, Civil and Construction Sciences:61476", author = "M. Rad and M. Dolatshahi Pirooz and M. Esmayili", title = "Effects of Sea Water Level Fluctuations on Seismic Response of Jacket Type Offshore Platforms", abstract = "To understand the seismic behavior of the offshore
structures, the dynamic interaction of the water-structure-soil should
be assessed. In this regard the role of the water dynamic properties in
magnifying or reducing of the effects of earthquake induced motions
on offshore structures haven't been investigated in precise manner in
available literature. In this paper the sea water level fluctuations
effects on the seismic behavior of a sample of offshore structures has
been investigated by emphasizing on the water-structure interaction
phenomenon. For this purpose a two dimensional finite element
model of offshore structures as well as surrounded water has been
developed using ANSYS software. The effect of soil interaction with
embedded pile foundation has been imposed by using a series of
nonlinear springs in horizontal and vertical directions in soil-piles
contact points. In the model, the earthquake induced motions have
been applied on springs and consequently the motions propagated
upward to the structure and surrounded water. As a result of
numerical study, the horizontal deformations of the offshore deck as
well as internal force and buckling coefficient in structural elements
have been recorded and controlled with and without water presence.
In part of study a parametric study has been accomplished on sea
water level fluctuations and effect of this parameter has been studied
on the aforementioned numerical results.", keywords = "Fluid-Structure Interaction, Jacket, Sea Water Level,Seismic Loading.", volume = "4", number = "10", pages = "332-6", }