2016 Vol. 38, No. 9
Display Method:
2016, 38(9): .
Abstract:
2016, 38(9): 1-12.
doi: 10.3969/j.issn.0253-4193.2016.09.001
Abstract:
Based on the cruise conductivity-temperature-depth(CTD) data, the sea level, current and near bottom temperature data from seabed-based observations, and the wind field data during June to July, 2010, this paper studied the response of upwelling in eastern Guangdong and southern Fujian coastal seas to the local wind variation, while the influence of typhoon was relatively weak. The main conclusions are as follows: (1) The results of power spectrum analyses showed that, the alongshore wind speed component, sea level, current and near bottom temperature showed similar variations with the significant periods of fluctuations in 3.5-4.0 d, 5.0-5.5 d and 8.3-9.0 d. The variation of alongshore wind speed component brought about the fluctuation of the upwelling intensity in 3-9 d frequency band. (2) The response process of upwelling to the local wind variation was like this. Surface water was transported offshore within the surface Ekman layer because of the alongshore component of wind stress. Coastal sea level dropped, a cross-shore pressure gradient set up. The pressure gradient would change following the local wind variation, resulting in enhanced(or weakened) alongshore current and enhanced(or weakened) near bottom cross-shore current. Near bottom temperature changed according to the variation of near bottom cross-shore current. (3) The results of correlation analyses and cross-spectral analysis showed that, the variation of alongshore wind speed component would influence near bottom temperature in upwelling zone within 3 days. The lag time for sea level's response to alongshore wind variation, near bottom (34 m) cross-shore current's response to sea level variation and near bottom temperature's response to near bottom (34 m) cross-shore current variation were 24 h, 7 h and 27 h respectively.
Based on the cruise conductivity-temperature-depth(CTD) data, the sea level, current and near bottom temperature data from seabed-based observations, and the wind field data during June to July, 2010, this paper studied the response of upwelling in eastern Guangdong and southern Fujian coastal seas to the local wind variation, while the influence of typhoon was relatively weak. The main conclusions are as follows: (1) The results of power spectrum analyses showed that, the alongshore wind speed component, sea level, current and near bottom temperature showed similar variations with the significant periods of fluctuations in 3.5-4.0 d, 5.0-5.5 d and 8.3-9.0 d. The variation of alongshore wind speed component brought about the fluctuation of the upwelling intensity in 3-9 d frequency band. (2) The response process of upwelling to the local wind variation was like this. Surface water was transported offshore within the surface Ekman layer because of the alongshore component of wind stress. Coastal sea level dropped, a cross-shore pressure gradient set up. The pressure gradient would change following the local wind variation, resulting in enhanced(or weakened) alongshore current and enhanced(or weakened) near bottom cross-shore current. Near bottom temperature changed according to the variation of near bottom cross-shore current. (3) The results of correlation analyses and cross-spectral analysis showed that, the variation of alongshore wind speed component would influence near bottom temperature in upwelling zone within 3 days. The lag time for sea level's response to alongshore wind variation, near bottom (34 m) cross-shore current's response to sea level variation and near bottom temperature's response to near bottom (34 m) cross-shore current variation were 24 h, 7 h and 27 h respectively.
2016, 38(9): 13-20.
doi: 10.3969/j.issn.0253-4193.2016.09.002
Abstract:
Mode-2 internal solitary wave (ISW) is seldom observed in real oceans. In this study, the characteristics of one prototypical mode-2 ISW over the continental shelf of northern South China (SCS) were analyzed, by using of mooring measurements with fine spatial and temporal resolutions. It was shown that the current core of mode-2 ISW appeared at a depth of 135 m, with a maximum of 0.66 m/s. The currents along the ISW propagation direction covered a depth range of 80~170 m, and the currents at a reverse direction were observed near the surface and bottom. Vertical mode analysis revealed that observed vertical structure of horizontal current of ISWs matched well with the theoretical results. At the trough of mode-2 ISW, the depth-integrated horizontal kinetic energy (KE) density could reach 14 kJ/m2. Along the wave front, the KE of mode-2 ISW was up to 5.98 MJ/m. Although the kinetic energy of the mode-2 ISW was one order smaller than that of strong mode-1 ISW, its current shear of up to 0.045 s-1 was two times as strong as that of mode-1 ISW, which suggested a more rapid energy dissipation.
Mode-2 internal solitary wave (ISW) is seldom observed in real oceans. In this study, the characteristics of one prototypical mode-2 ISW over the continental shelf of northern South China (SCS) were analyzed, by using of mooring measurements with fine spatial and temporal resolutions. It was shown that the current core of mode-2 ISW appeared at a depth of 135 m, with a maximum of 0.66 m/s. The currents along the ISW propagation direction covered a depth range of 80~170 m, and the currents at a reverse direction were observed near the surface and bottom. Vertical mode analysis revealed that observed vertical structure of horizontal current of ISWs matched well with the theoretical results. At the trough of mode-2 ISW, the depth-integrated horizontal kinetic energy (KE) density could reach 14 kJ/m2. Along the wave front, the KE of mode-2 ISW was up to 5.98 MJ/m. Although the kinetic energy of the mode-2 ISW was one order smaller than that of strong mode-1 ISW, its current shear of up to 0.045 s-1 was two times as strong as that of mode-1 ISW, which suggested a more rapid energy dissipation.
2016, 38(9): 21-31.
doi: 10.3969/j.issn.0253-4193.2016.09.003
Abstract:
Strong ocean current in the Northwestern Pacific has significant impact on the characteristics and distribution of ocean wave, especially during typhoon. A coupled current-wave modeling system based on the ROMS model and SWAN model is applied to study the current-induced modulation of significant wave height by wave-current interaction during Typhoon Danas, Typhoon Nari and Typhoon Wipha through October 6-17, 2013. The results indicated that the ocean current had significant impact on the simulation of significant wave height in the coupled modeling system. The significant wave height is closer to buoy observation when wave and current are coupled. The maximum enhanced significant wave height due to current is up to 1 m. It's indicated that the significant wave height always increases (decreases) when the wave direction is against (along) the background ocean current. And the effects of wave-current interactions are not only local but also spread a long distance with the propagation of wave. The wave-current coupled modeling system is important for wave forecasting in the Northwestern Pacific. The current induced in the coupled modeling system would contribute to high-precision ocean wave forecast.
Strong ocean current in the Northwestern Pacific has significant impact on the characteristics and distribution of ocean wave, especially during typhoon. A coupled current-wave modeling system based on the ROMS model and SWAN model is applied to study the current-induced modulation of significant wave height by wave-current interaction during Typhoon Danas, Typhoon Nari and Typhoon Wipha through October 6-17, 2013. The results indicated that the ocean current had significant impact on the simulation of significant wave height in the coupled modeling system. The significant wave height is closer to buoy observation when wave and current are coupled. The maximum enhanced significant wave height due to current is up to 1 m. It's indicated that the significant wave height always increases (decreases) when the wave direction is against (along) the background ocean current. And the effects of wave-current interactions are not only local but also spread a long distance with the propagation of wave. The wave-current coupled modeling system is important for wave forecasting in the Northwestern Pacific. The current induced in the coupled modeling system would contribute to high-precision ocean wave forecast.
2016, 38(9): 32-45.
doi: 10.3969/j.issn.0253-4193.2016.09.004
Abstract:
Based on ensemble-variational hybrid data assimilation system, the anisotropic and some flow-dependent background error covariance was introduced into data assimilation systems by combining historical forecast error covariance with the static background error covariance. The historical forecast error covariance was calculated from the forecasts of difference between the different forecasts respectively valid at the same time. Single observation experiments demonstrate that the background error covariance modeled by the new method has the anisotropic and some flow-dependent information. A series of assimilation and simulation experiments for typhoon Fanapi show that the track, minimum sea level pressure and wind speed using the method were better than that of 3DVar. The historical forecast error covariance not need ensemble forecasts and the anisotropic and some flow-dependent information are taken into account in the data assimilation system, then the cost of the calculation is similar to that of 3DVar, so the method would be beneficial to some operational centers and research communities with limited computational resources.
Based on ensemble-variational hybrid data assimilation system, the anisotropic and some flow-dependent background error covariance was introduced into data assimilation systems by combining historical forecast error covariance with the static background error covariance. The historical forecast error covariance was calculated from the forecasts of difference between the different forecasts respectively valid at the same time. Single observation experiments demonstrate that the background error covariance modeled by the new method has the anisotropic and some flow-dependent information. A series of assimilation and simulation experiments for typhoon Fanapi show that the track, minimum sea level pressure and wind speed using the method were better than that of 3DVar. The historical forecast error covariance not need ensemble forecasts and the anisotropic and some flow-dependent information are taken into account in the data assimilation system, then the cost of the calculation is similar to that of 3DVar, so the method would be beneficial to some operational centers and research communities with limited computational resources.
2016, 38(9): 46-53.
doi: 10.3969/j.issn.0253-4193.2016.09.005
Abstract:
The sediment cores, from shallow seafloor in depth of 100-400 meters (about 2 m depth buried) in an area of the South China Sea, have been performed a simultaneous triaxial strain-acoustic measurement near seabed water pressure. The results show that the sediment longitudinal wave velocity has two characteristics: (1) the longitudinal wave velocity in sediments keeps changing in the process of strain applied from start to end; (2) the average of the speed of sound changes from large to small and then from small to large with the average of the static elastic modulus increasing, and there is a minimum during the course of the average of the speed of sound change. These results are related to physical and mechanical properties and confining pressure of the shallow seafloor sediments, and the changes of the state in which particles of these sediments combine together. In addition, sediment dynamic elastic modulus and porosity has a good negative correlation, and that results from increases of the water content with increases of porosity. Dynamic elastic modulus is 10 to 100 times the static elastic modulus, since the large difference between the strain magnitude resulted from triaxial strain-test and the one generated by wave vibrations is primarily related to that. Two empirical formulas of dual complex parameters-velocity and porosity-velocity were established with the experimentally measured data in this paper. The analysis of results shows that the error in sound speed predicted by the formula of composite double parameters-velocity is approximately a quarter of that predicted by the formula of the porosity-velocity, and it shows that the formula of composite double parameters-velocity is more effective.
The sediment cores, from shallow seafloor in depth of 100-400 meters (about 2 m depth buried) in an area of the South China Sea, have been performed a simultaneous triaxial strain-acoustic measurement near seabed water pressure. The results show that the sediment longitudinal wave velocity has two characteristics: (1) the longitudinal wave velocity in sediments keeps changing in the process of strain applied from start to end; (2) the average of the speed of sound changes from large to small and then from small to large with the average of the static elastic modulus increasing, and there is a minimum during the course of the average of the speed of sound change. These results are related to physical and mechanical properties and confining pressure of the shallow seafloor sediments, and the changes of the state in which particles of these sediments combine together. In addition, sediment dynamic elastic modulus and porosity has a good negative correlation, and that results from increases of the water content with increases of porosity. Dynamic elastic modulus is 10 to 100 times the static elastic modulus, since the large difference between the strain magnitude resulted from triaxial strain-test and the one generated by wave vibrations is primarily related to that. Two empirical formulas of dual complex parameters-velocity and porosity-velocity were established with the experimentally measured data in this paper. The analysis of results shows that the error in sound speed predicted by the formula of composite double parameters-velocity is approximately a quarter of that predicted by the formula of the porosity-velocity, and it shows that the formula of composite double parameters-velocity is more effective.
2016, 38(9): 54-63.
doi: 10.3969/j.issn.0253-4193.2016.09.006
Abstract:
Aimed to reveal status of existing sea reclamation resource and improve monitoring level of marine space, the conception of existing sea reclamation resource is defined and divided it into encircled and unfilled region, reclamation and non construction region, low density building region, low-lying ponds, low economic salt ponds and low economic fishing ponds, and consumption types such as industrial region, cities and town region. Then high resolution satellite remote sensing images was employed to obtain existing sea reclamation resource information. And the technique flow of remote sensing image classification for existing sea reclamation resource based on object-oriented method established, and existing sea reclamation resource index was created for existing sea reclamation resource monitoring and analysis. South coast of Yingkou was chose as study areas based on above. The results show that remote sensing image classification for existing sea reclamation resource based on object-oriented method established in this paper can extract existing sea reclamation resource information with accuracy rate more than 90%. Reclamation and non construction region, low economic salt ponds and low economic fishing ponds account for 62.51% areas of total existing sea reclamation resource. The existing sea reclamation resource index is 0.49 for total study areas and 0.66 for north part, 0.44 for middle part and 0.37 for south part.
Aimed to reveal status of existing sea reclamation resource and improve monitoring level of marine space, the conception of existing sea reclamation resource is defined and divided it into encircled and unfilled region, reclamation and non construction region, low density building region, low-lying ponds, low economic salt ponds and low economic fishing ponds, and consumption types such as industrial region, cities and town region. Then high resolution satellite remote sensing images was employed to obtain existing sea reclamation resource information. And the technique flow of remote sensing image classification for existing sea reclamation resource based on object-oriented method established, and existing sea reclamation resource index was created for existing sea reclamation resource monitoring and analysis. South coast of Yingkou was chose as study areas based on above. The results show that remote sensing image classification for existing sea reclamation resource based on object-oriented method established in this paper can extract existing sea reclamation resource information with accuracy rate more than 90%. Reclamation and non construction region, low economic salt ponds and low economic fishing ponds account for 62.51% areas of total existing sea reclamation resource. The existing sea reclamation resource index is 0.49 for total study areas and 0.66 for north part, 0.44 for middle part and 0.37 for south part.
2016, 38(9): 64-75.
doi: 10.3969/j.issn.0253-4193.2016.09.007
Abstract:
Based on the field and laboratory bio-optical datasets from the May and August cruises in the Pearl River Estuary in 2014, the variability of bio-optical parameters was analyzed to examine the dominant optically active components in a highly turbid water. Using the simulated and field MODIS data, the retrieval algorithms for estimation of the absorption coefficients at a specific wavelength of water components were developed and classified following the IOCCG reports, to assess the spatial and temporal variability of dominant optically active components in the Pearl River Estuary. The results demonstrated that ad, ag or both of them (adg) dominated the optical properties of water in this estuary, with adg accounting for an average of 76.9% in 2011, followed by ag and ad. Furthermore, ad(442) and adg(442) were both well positively correlated with cISS, which were shown to provide comparable information on CDOM and detritus present.
Based on the field and laboratory bio-optical datasets from the May and August cruises in the Pearl River Estuary in 2014, the variability of bio-optical parameters was analyzed to examine the dominant optically active components in a highly turbid water. Using the simulated and field MODIS data, the retrieval algorithms for estimation of the absorption coefficients at a specific wavelength of water components were developed and classified following the IOCCG reports, to assess the spatial and temporal variability of dominant optically active components in the Pearl River Estuary. The results demonstrated that ad, ag or both of them (adg) dominated the optical properties of water in this estuary, with adg accounting for an average of 76.9% in 2011, followed by ag and ad. Furthermore, ad(442) and adg(442) were both well positively correlated with cISS, which were shown to provide comparable information on CDOM and detritus present.
2016, 38(9): 76-88.
doi: 10.3969/j.issn.0253-4193.2016.09.008
Abstract:
Based on 4 530 km high resolution seismic data and core data, we divide the sequence stratigraphy in the Taiwan Strait since late Pleistocene, using the method of high resolution seismic stratigraphy. The main reflective interfaces R0,R1,R2,R3 and R4 correspond to the seafloor, the high sea level at 3 ka BP, the maximum flooding surface, the transgressive surface and the type I sequence boundary, respectively. And the depositional sequence includes four stratigraphic units: the late Holocene neritic-littoral deposits A, the middle Holocene shallow sea deposits B, the early Holocene transgression sediments C, and the late Pleistocene continental fluvial deposits D. In response to the sea level changes, the strait formed low-stand deposits (LST), transgression deposits (TST), and high-stand deposits (HST) in turn. Furthermore, typical seismic facies are studied, and a new viewpoint about the wedge at the Taichung shoal (Yun-chang Rise) is proposed: the wedge is delta deposition, of which the sediments mainly come from Taiwan, formed since mid-Holocene, and transformed into a tidal sand ridge by combined waves and tidal currents. Besides, we identify the late Pleistocene and the early Holocene paleo-channel depositions, of which the forming time difference is mainly caused by sea level change and its topography.
Based on 4 530 km high resolution seismic data and core data, we divide the sequence stratigraphy in the Taiwan Strait since late Pleistocene, using the method of high resolution seismic stratigraphy. The main reflective interfaces R0,R1,R2,R3 and R4 correspond to the seafloor, the high sea level at 3 ka BP, the maximum flooding surface, the transgressive surface and the type I sequence boundary, respectively. And the depositional sequence includes four stratigraphic units: the late Holocene neritic-littoral deposits A, the middle Holocene shallow sea deposits B, the early Holocene transgression sediments C, and the late Pleistocene continental fluvial deposits D. In response to the sea level changes, the strait formed low-stand deposits (LST), transgression deposits (TST), and high-stand deposits (HST) in turn. Furthermore, typical seismic facies are studied, and a new viewpoint about the wedge at the Taichung shoal (Yun-chang Rise) is proposed: the wedge is delta deposition, of which the sediments mainly come from Taiwan, formed since mid-Holocene, and transformed into a tidal sand ridge by combined waves and tidal currents. Besides, we identify the late Pleistocene and the early Holocene paleo-channel depositions, of which the forming time difference is mainly caused by sea level change and its topography.
2016, 38(9): 89-99.
doi: 10.3969/j.issn.0253-4193.2016.09.009
Abstract:
Reasonably and quantitatively determining subdivisions of sedimentary dynamic environment is an important basis of understanding regional sedimentary dynamic processes. Based on the grain distribution data of the surface sediment samples, the sedimentary dynamic environment in the Yellow River subaqueous delta area has been classified, identified and represented by the methods of fuzzy c-means clustering (FCM), triangle illustration and kriging. The results show that the sedimentary dynamic environment of the study area can been classified into 3 categories and they indicate the dynamic sedimentary environments of scour, deposition and mixing of scour and deposition, respectively. And the membership degree maps of the three categories of sedimentary dynamic environments have a function of indicating the occurance probabilities of the different environments at certain places and also can show their dominant areas. Meanwhile the sedimentary dynamic environment map, generated from the fuzzy membership degree values of the surface sediments, is highly identical with the spatial distribution pattern of the sedimentary dynamics in the study area, which means the mapping results are reasonable and effective. The study results have some reference values for the geomorphic evolution trend analysis and coastal protection work in the area of the Yellow River Delta.
Reasonably and quantitatively determining subdivisions of sedimentary dynamic environment is an important basis of understanding regional sedimentary dynamic processes. Based on the grain distribution data of the surface sediment samples, the sedimentary dynamic environment in the Yellow River subaqueous delta area has been classified, identified and represented by the methods of fuzzy c-means clustering (FCM), triangle illustration and kriging. The results show that the sedimentary dynamic environment of the study area can been classified into 3 categories and they indicate the dynamic sedimentary environments of scour, deposition and mixing of scour and deposition, respectively. And the membership degree maps of the three categories of sedimentary dynamic environments have a function of indicating the occurance probabilities of the different environments at certain places and also can show their dominant areas. Meanwhile the sedimentary dynamic environment map, generated from the fuzzy membership degree values of the surface sediments, is highly identical with the spatial distribution pattern of the sedimentary dynamics in the study area, which means the mapping results are reasonable and effective. The study results have some reference values for the geomorphic evolution trend analysis and coastal protection work in the area of the Yellow River Delta.
2016, 38(9): 100-109.
doi: 10.3969/j.issn.0253-4193.2016.09.010
Abstract:
In this paper,the monitoring data of Beichangshan Island coast landslide from March 2012 are obtained from the periodical and real time monitoring and warning system, which was established combining techniques such as unmanned aerial vehicle remote sensing, ground penetrating radar, 3D laser scanner and displacement sensors. Beichangshan Island coastal landslide is located near Shanhou Village, Changdao County, Shandong Province. It is extremely unstable due to the steep quarry face formed by unreasonable operation. The existence of joints and cracks as well as phyllite strata is the main internal factor of the landslide. And the main external factor is extreme conditions such as artificially quarrying and heavy rains. The mountain body tends to downslide on the whole, with the top showing a tensional outward trend. The cumulative sliding distance is more than 30 cm and the change of altitude is about 5-10 cm. The sliding distance has a strong positive correlation with the precipitation (i.e. a large sliding during heavy rain and a minor sliding during a light rain). The landslide might be unstable when the daily rainfall is over 80 mm. Natural factors and human factors both lead to the occurrence of the Beichangshan Island landslide, which makes the island landslide study of great importance.
In this paper,the monitoring data of Beichangshan Island coast landslide from March 2012 are obtained from the periodical and real time monitoring and warning system, which was established combining techniques such as unmanned aerial vehicle remote sensing, ground penetrating radar, 3D laser scanner and displacement sensors. Beichangshan Island coastal landslide is located near Shanhou Village, Changdao County, Shandong Province. It is extremely unstable due to the steep quarry face formed by unreasonable operation. The existence of joints and cracks as well as phyllite strata is the main internal factor of the landslide. And the main external factor is extreme conditions such as artificially quarrying and heavy rains. The mountain body tends to downslide on the whole, with the top showing a tensional outward trend. The cumulative sliding distance is more than 30 cm and the change of altitude is about 5-10 cm. The sliding distance has a strong positive correlation with the precipitation (i.e. a large sliding during heavy rain and a minor sliding during a light rain). The landslide might be unstable when the daily rainfall is over 80 mm. Natural factors and human factors both lead to the occurrence of the Beichangshan Island landslide, which makes the island landslide study of great importance.
2016, 38(9): 110-117.
doi: 10.3969/j.issn.0253-4193.2016.09.011
Abstract:
Submarine pipelines, in state of suspended or laid on the seafloor, were important transmissible channels of crude oil and natural gas in marine engineering. For the laid-on-seafloor pipelines, in order to get the axial and normal drag force of the pipeline under different impact angles, the CFD method was used to simulate the action of submarine landslide affecting on the submarine pipeline. Further, it was analysed that the relationship between the cross section shape of the pipeline in the impact direction and the drag force of the pipeline.The research extended the predecessors' work, enriched the calculated results of the longitudinal and the normal drag coefficient, and obtained the formula for estimating the impact force of the debris flow on the seabed pipelines.
Submarine pipelines, in state of suspended or laid on the seafloor, were important transmissible channels of crude oil and natural gas in marine engineering. For the laid-on-seafloor pipelines, in order to get the axial and normal drag force of the pipeline under different impact angles, the CFD method was used to simulate the action of submarine landslide affecting on the submarine pipeline. Further, it was analysed that the relationship between the cross section shape of the pipeline in the impact direction and the drag force of the pipeline.The research extended the predecessors' work, enriched the calculated results of the longitudinal and the normal drag coefficient, and obtained the formula for estimating the impact force of the debris flow on the seabed pipelines.
2016, 38(9): 118-125.
doi: 10.3969/j.issn.0253-4193.2016.09.012
Abstract:
Based on analyzing the natural scour near the axis of the bridge by data of topographical, this paper used a multi-beam echo-sounding system to study local scour around bridge piers. The results showed that the axis of the bridge and the riverbed near main piers presents erosion evolutionary trend. Upstream the pier, there is a serius erosion while sediments deposit at the mid of pier. Downstream the pier, weak erosion is also found. The largest scour depth of the main pier is about 4 m. The local scour shape of the main pier looks like "double kidneys". The angle of ebb coming current is 10 degree, as well as the scour depth and scope on the south side of the main pier is larger than that on the north.
Based on analyzing the natural scour near the axis of the bridge by data of topographical, this paper used a multi-beam echo-sounding system to study local scour around bridge piers. The results showed that the axis of the bridge and the riverbed near main piers presents erosion evolutionary trend. Upstream the pier, there is a serius erosion while sediments deposit at the mid of pier. Downstream the pier, weak erosion is also found. The largest scour depth of the main pier is about 4 m. The local scour shape of the main pier looks like "double kidneys". The angle of ebb coming current is 10 degree, as well as the scour depth and scope on the south side of the main pier is larger than that on the north.
2016, 38(9): 126-133.
doi: 10.3969/j.issn.0253-4193.2016.09.013
Abstract:
Sea ice strength, as one of the most important mechanical parameters affecting the macro-deformation characteristics and micro-failure features of sea ice, plays a significant role both on sea ice dynamics of geophysical scale and ice load of offshore structures. In this study, sea ice mechanical and physical parameters of the Bohai Sea were measured in field and laboratory tests. The relationships between sea ice strengths and the brine volume and stress rates are analyzed based on the experimental data. The results demonstrate that the exponential function can express the relationship between the sea ice strengths and the square root of brine volume, while the linear function is perfect for the relationship between sea ice strengths and the stress rate. Finally, the unified representation of sea ice strengths under the influences of brine volume and stress rate is established. This present work can be benefit for the determination of sea ice strength in the engineering applications.
Sea ice strength, as one of the most important mechanical parameters affecting the macro-deformation characteristics and micro-failure features of sea ice, plays a significant role both on sea ice dynamics of geophysical scale and ice load of offshore structures. In this study, sea ice mechanical and physical parameters of the Bohai Sea were measured in field and laboratory tests. The relationships between sea ice strengths and the brine volume and stress rates are analyzed based on the experimental data. The results demonstrate that the exponential function can express the relationship between the sea ice strengths and the square root of brine volume, while the linear function is perfect for the relationship between sea ice strengths and the stress rate. Finally, the unified representation of sea ice strengths under the influences of brine volume and stress rate is established. This present work can be benefit for the determination of sea ice strength in the engineering applications.
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