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Study on strength properties and soil behaviour type classification of huanghe river delta silts based on variable rate piezocone penetration test

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Acta Oceanologica Sinica 2023年第11期42卷 146-158页

作者： Yunuo Liu Guoqing Lin Yan Zhang Shenggui Deng Lei Guo Tao Liu Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering Ocean University of ChinaQingdao 266100China College of Environmental Science and Engineering Ocean University of ChinaQingdao 266100China Key Lab of Submarine Geosciences and Prospecting Techniques MOE China Ocean University of ChinaQingdao 266100China College of Marine Geosciences Ocean University of ChinaQingdao 266100China Institute of Marine Science and Technology Shandong UniversityQingdao 266237China Qingdao National Laboratory for Marine Science and Technology Qingdao 266100China

Fine-grained silt is widely distributed in the huanghe river delta(HRD)in China,and the sedimentary structure is complex,meaning that the clay content in the silt is *** piezocone penetration test(CPTu)is the most widely approved in situ test *** can be used to invert soil properties and interpret soil *** analyse the strength properties of surface sediments in the HRD,this paper evaluated the friction angle and its inversion formula through the CPTu penetration test and monotonic simple shear test and other soil unit *** evaluation showed that the empirical formula proposed by Kulhawy and Mayne had better prediction and inversion *** HRD silts with clay contents of 9.2%,21.4%and 30.3%were selected as samples for the CPTu variable rate penetration *** results show as follows.(1)The effects of the clay content on the tip resistance and the pore pressure of silt under different penetration rates were *** tip resistance Q_t is strongly dependent on the clay content of the silt,the B_(q)value of the silt tends to 0 and is not significantly affected by the change of the CPTu penetration rate.(2)Five soil behavior type classification charts and three soil behavior type indexes based on CPTu data were *** results show that the soil behavior type classification chart based on soil behavior type index ISBT,the Robertson 2010 behavior type classification chart are more suitable for the silty soil in the HRD.

关键词： huanghe river delta piezocone penetration test silty soils clay content friction angle soil behaviour type classification

Deposits and depositional sequence nearby Iluanghe Harbour in the huanghe river delta

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Acta Oceanologica Sinica 1993年第4期12卷 605-615页

作者： S.D.Nio J.H.Van dern Berg A.Van Gelder Comparative Sedimentary Division University of Utrecht The NetherlandsGeographical Department University of Utrecht The NetherlandsComparative Sedimentary Division University of Utrecht The Netherlands

The sedimentary sequence of the upper 4 m deposits in the huanghe Harbour Pit is as follows, 1, Distributary mouth bar deposits formed before 1964; 2. lower delta plain (tidal flat) and subaqueous delta lateral deposits formed in the period of 1964-1972; 3. deposits of crevasse splay and distributary channel near mouth, formed in the period of 1972-1974; 4. tidal flat deposits formed in the period of 1975-1984. The sequence shows superimposition of sedimentary environments parallel to coastline.

关键词： huanghe river delta depositional sequence

Modeling of suspended sediment transport with wave-induced longshore current in huanghe (Yellow) river delta

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Acta Oceanologica Sinica 2009年第3期28卷 65-74页

作者： LI Changliang LIANG Bingchen ZHANG Jing College of Petroleum Engineering China University of Petroleum（East China） Qingdao266555 China Engineering College Ocean University of China Qingdao 266100 China

A three-dimensional suspended sediment model （SED） developed by the present authors is coupled with the combinatorial model of COHERENS （Luyten et al., 1999）（the three-dimensional coupled hydrodynamical-ecological model for Regional and Shelf Seas） and SWAN （Holthuijsen et al., 2004）（the third generation wave model）. SWAN is regarded as a subroutine of COHERENS and gets time- and space-varying current velocity and surface elevation from COHERENS. COHERENS gets time- and space- varying wave relevant parameters provided by SWAN. Effects of wave on current are applied in bottom shear stress, wave-induced depth-dependent radiation stress and surface drag coefficient calculation. At the same time, the damping function of suspended sediment on turbulence is introduced into COHERENS. So the sediment model SED has feedback on circulation model COHERENS. The SED obtains current associated parameters from COHERENS. Then a coupled hydrodynamic-sediment model COHERENS-SED being able to account for interaction between wave and current is obtained. COHERENS-SED is adopted to simulate three-dimensional suspended sediment transport in the huanghe river delta. In terms of simulation results, there is obvious difference between top and bottom layer of wave-induced longshore current. The values of time series of sediment concentration gotten by COHERENS-SED have, generally, an accepted agreement extent with measurement. Significant wave heights and wave periods obtained by COHERENS-SED show that wave simulation case with currentts effect can give better agreement extent with measurement than case without current＇s effect. In the meantime, suspended sediment concentration distributing rule obtained by COHERENS-SED is similar to former researches and measurement.

关键词： huanghe river delta suspended sediment wave-induced longshore current COHERENS SWAN COHERENS-SED

Spatial-temporal changes of tidal flats in the huanghe river delta using Landsat TM/ETM+ images

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Journal of Geographical Sciences 2004年第3期14卷 366-374页

作者：樊辉黄海军 Institute of Oceanology CAS Institute of Oceanology CAS Qingdao 266071 China

Integrating remote sensing, geographic information system (GIS) and fractal theory, change characteristics of tidal flats and tidal creeks in the huanghe (Yellow) river delta over the period of 1986-2001 were discussed. The results show that evolutions of tidal flats throughout the huanghe river delta are influenced by various factors, and that progressive succession and regression of tidal flats concur in different coastal segments of the delta. Human activities have played an increasingly important role in the succession process of tidal flats. Due to land reclamation in coastal zones of the delta in the last 15 years, lots of tidal flats were occupied, the artificial coastline migrated seaward (the maximum change rate was 0.8 kmyr-1) and tidal creeks became sparser (the highest decreasing rate of length of tidal creeks was 14.9 kmyr-1). Except for two coastal segments from the Tiaohe Estuary to the 106 Station and from the south of the huanghe river mouth to the north of the Xiaodao river Estuary, fractal dimension values of tidal creeks in the remaining coastal segments of the delta decreased. In addition, the time dimension, sediment fluxes into the sea, waves and tidal-currents have profound influences on the evolution process of tidal flats. Four types of tidal flats-river-dominated tidal flats, tide-dominated tidal flats, wave-dominated tidal flats and man-dominated tidal flats can be identified. Owing to the intensification of human activities in coastal zones of the delta, man-dominated tidal flats have become the main kind of tidal flats.

关键词： huanghe river delta tidal flats tidal creeks spatial-temporal change fractal dimension remote sensing

Predictive Vegetation Mapping Approach Based on Spectral Data, DEM and Generalized Additive Models

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Chinese Geographical Science 2013年第3期23卷 331-343页

作者： SONG Chuangye HUANG Chong LIU Huiming State Key Laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of Sciences State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Satellite Environment Centre Ministry of Environmental Protection

This study aims to provide a predictive vegetation mapping approach based on the spectral data, DEM and Generalized Additive Models (GAMs). GAMs were used as a prediction tool to describe the relationship between vegetation and environmental variables, as well as spectral variables. Based on the fitted GAMs model, probability map of species occurrence was generated and then vegetation type of each grid was defined according to the probability of species occurrence. Deviance analysis was employed to test the goodness of curve fitting and drop contribution calculation was used to evaluate the contribution of each predictor in the fitted GAMs models. Area under curve (AUC) of Receiver Operating Characteristic (ROC) curve was employed to assess the results maps of probability. The results showed that: 1) AUC values of the fitted GAMs models are very high which proves that integrating spectral data and environmental variables based on the GAMs is a feasible way to map the vegetation. 2) Prediction accuracy varies with plant community, and community with dense cover is better predicted than sparse plant community. 3) Both spectral variables and environmental variables play an important role in mapping the vegetation. However, the contribution of the same predictor in the GAMs models for different plant communities is different. 4) Insufficient resolution of spectral data, environmental data and confounding effects of land use and other variables which are not closely related to the environmental conditions are the major causes of imprecision.

关键词： vegetation mapping Generalized Additive Models (GAMs) SPOT Receiver Operating Characteristic (ROC) GeneralizedRegression Analysis and Spatial Predictions (GRASP) huanghe river delta