scholarly journals ENGINEERING PROPERTIES OF SEA FLOOR SEDIMENTS FROM LA JOLLA CANYON

1972 ◽  
Vol 1 (13) ◽  
pp. 82
Author(s):  
Iraj Noorany ◽  
Robert A. Zinser
Keyword(s):  
Grain Size ◽  
Underwater Vehicle ◽  
Engineering Properties ◽  
High Plasticity ◽  
Index Properties ◽  
Near Surface ◽  
Sea Floor ◽  
Size Index ◽  
La Jolla

Near surface sea floor sediments were obtained "by the tracked underwater •vehicle RUM from four locations on the floor of the La Jolla Canyon. The sediments were clayey silts of high plasticity. The engineering properties of the sediments, including grain size, index properties, strength and compressibility, were determined.

scholarly journals KETERDAPATAN MINERAL LEMPUNG SMEKTIT YANG MEMPUNYAI SIFAT PLASTISITAS TINGGI DI PERAIRAN CIREBON, JAWA BARAT

2017 ◽  
Vol 14 (1) ◽  
Author(s):  
Purnomo Raharjo ◽  
Lili Sarmili
Keyword(s):  
Grain Size ◽  
Water Content ◽  
Clay Minerals ◽  
Plasticity Index ◽  
Engineering Properties ◽  
High Plasticity ◽  
Mineral Analysis ◽  
Undisturbed Soil ◽  
Very High

Salah satu masalah dalam pembangunan infrastruktur di atas tanah lempung adalah sifatnya  yang mengembang (swelling). Tujuan penelitian adalah untuk mengetahui sifat fisik dan keteknikan tanah lempung di perairan Cirebon. Metode penelitian meliputi pemboran, besar butir, analisis mineral dan uji Atterberg. Hasil analisis ukuran butir dari contoh tanah tidak terganggu didominasi oleh lempung, sedangkan mineral lempungnya menunjukkan jenis smektit yang lebih banyak dari pada kaolinit. Kaolinit dan montmorilonit  mempunyai kadar air yang tinggi. Nilai plastisitasnya tinggi sampai sangat tinggi dengan nilai aktifitas di atas 0,5. Berdasarkan hasil uji Atterberg plastisitas Index lempung  dengan nilai >17 dapat dikategorikan bersifat plastisitas tinggi dan kompak (High Plasticity and cohesive). Kata kunci : Mineral smektit, plastisitas tinggi, uji Atterberg, analisis mineral lempung, perairan Cirebon.One of the problems in the construction of infrastructure on top of clay is that it is expanding (swelling). The research objective was to determine the physical and engineering properties of clay in the waters of Cirebon. Methods of research include drilling, grain size analyses, mineral analysis and Atterberg test. The results of the analysis of the grain size of the sample undisturbed soil dominated by clay which are indicated and dominated by smectite rather than kaolinite. Kaolinite and monmorilonite are high in water content. The plasticity value  is high to very high with activity value above 0.5. Based on the results of Atterberg test, clay plasticity index with values >17 can be considered to be of high plasticity and compact (High Plasticity and cohesive).Keywords: smectite minerals, high plasticity, Atterberg test, clay minerals analysis, Cirebon waters.

scholarly journals Unified Evaluation of Consolidation Parameters for Low to High Plastic Range of Cohesive Soils

2021 ◽  
Vol 40 (1) ◽  
pp. 93-103
Author(s):  
Zia ur Rehman State ◽  
Khalid Farooq ◽  
Hassan Mujtaba ◽  
Usama Khalid
Keyword(s):  
Cohesive Soil ◽  
Soil Samples ◽  
Engineering Properties ◽  
Cohesive Soils ◽  
High Plasticity ◽  
Index Properties ◽  
Undisturbed Soil ◽  
Index Compression ◽  
The Right ◽  
Consolidation Parameters

Knowing the engineering properties of geomaterials is imperative to make the right decision while designing and executing any geotechnical project. For the economical and safe geotechnical design, quick characterization of the compressibility properties of the cohesive soil is often desirable; these properties are indeed tedious to determine through actual tests. Therefore, correlating the consolidation parameters of the soils with its index properties has a great significance in the geotechnical engineering field. Several attempts have been made in the past to develop correlations between the consolidation parameters and index properties of the cohesive soils, within certain limitations. However, there is still a need to develop such correlations based on the extensive database, composing of unified plasticity range of soils, i.e., low to high plasticity. In the current study, 148 undisturbed soil specimens were obtained from different areas of Pakistan. Out of which 120 samples were utilized to develop correlations, and 28 samples were used to check the validity of the developed correlations. In order to enhance the index properties database, 30 more bentonite mixed soil samples were prepared and tested accordingly. Correlations to envisage different consolidation parameters such as compression index, compression ratio and coefficient of volume compressibility were developed using 150 cohesive soil samples of low to high plasticity. In addition, the performance of these developed correlations was verified on a set of 40 soil samples and compared with the performance of different correlations available in the literature. The percentage deviation in the prediction of compressibility characteristics through developed correlations in the present study was found to be very less, which endorsed the excellent reliability of the developed correlations.

scholarly journals Compressibility behaviour of remoulded, fine-grained soils and correlation with index properties

2000 ◽  
Vol 37 (3) ◽  
pp. 712-722 ◽  
Author(s):  
A Sridharan ◽  
H B Nagaraj
Keyword(s):  
Liquid Limit ◽  
Plasticity Index ◽  
Engineering Properties ◽  
Test Results ◽  
Index Properties ◽  
Initial Water ◽  
Fine Grained ◽  
Wide Range ◽  
The Relationship ◽  
Water Contents

Correlating engineering properties with index properties has assumed greater significance in the recent past in the field of geotechnical engineering. Although attempts have been made in the past to correlate compressibility with various index properties individually, all the properties affecting compressibility behaviour have not been considered together in any single study to examine which index property of the soil correlates best with compressibility behaviour, especially within a set of test results. In the present study, 10 soils covering a sufficiently wide range of liquid limit, plastic limit, and shrinkage limit were selected and conventional consolidation tests were carried out starting with their initial water contents almost equal to their respective liquid limits. The compressibility behaviour is vastly different for pairs of soils having nearly the same liquid limit, but different plasticity characteristics. The relationship between void ratio and consolidation pressure is more closely related to the shrinkage index (shrinkage index = liquid limit - shrinkage limit) than to the plasticity index. Wide variations are seen with the liquid limit. For the soils investigated, the compression index relates better with the shrinkage index than with the plasticity index or liquid limit.Key words: Atterberg limits, classification, clays, compressibility, laboratory tests.

scholarly journals Sediment transport processes across the Tibetan Plateau inferred from robust grain-size end members in lake sediments

2014 ◽  
Vol 10 (1) ◽  
pp. 91-106 ◽  
Author(s):  
E. Dietze ◽  
F. Maussion ◽  
M. Ahlborn ◽  
B. Diekmann ◽  
K. Hartmann ◽  
...  
Keyword(s):  
Grain Size ◽  
Sediment Transport ◽  
Tibetan Plateau ◽  
Transport Processes ◽  
The Tibetan Plateau ◽  
Dust Deposition ◽  
Northerly Wind ◽  
Near Surface ◽  
Depositional Processes ◽  
End Members

Abstract. Grain-size distributions offer powerful proxies of past environmental conditions that are related to sediment sorting processes. However, they are often of multimodal character because sediments can get mixed during deposition. To facilitate the use of grain size as palaeoenvironmental proxy, this study aims to distinguish the main detrital processes that contribute to lacustrine sedimentation across the Tibetan Plateau using grain-size end-member modelling analysis. Between three and five robust grain-size end-member subpopulations were distinguished at different sites from similarly–likely end-member model runs. Their main modes were grouped and linked to common sediment transport and depositional processes that can be associated with contemporary Tibetan climate (precipitation patterns and lake ice phenology, gridded wind and shear stress data from the High Asia Reanalysis) and local catchment configurations. The coarse sands and clays with grain-size modes >250 μm and <2 μm were probably transported by fluvial processes. Aeolian sands (~200 μm) and coarse local dust (~60 μm), transported by saltation and in near-surface suspension clouds, are probably related to occasional westerly storms in winter and spring. Coarse regional dust with modes ~25 μm may derive from near-by sources that keep in longer term suspension. The continuous background dust is differentiated into two robust end members (modes: 5–10 and 2–5 μm) that may represent different sources, wind directions and/or sediment trapping dynamics from long-range, upper-level westerly and episodic northerly wind transport. According to this study grain-size end members of only fluvial origin contribute small amounts to mean Tibetan lake sedimentation (19± 5%), whereas local to regional aeolian transport and background dust deposition dominate the clastic sedimentation in Tibetan lakes (contributions: 42 ± 14% and 51 ± 11%). However, fluvial and alluvial reworking of aeolian material from nearby slopes during summer seems to limit end-member interpretation and should be crosschecked with other proxy information. If not considered as a stand-alone proxy, a high transferability to other regions and sediment archives allows helpful reconstructions of past sedimentation history.

scholarly journals Stabilization of Algerian Clayey Soils with Natural Pozzolana and Lime

2017 ◽  
Author(s):  
Khelifa Harichane ◽  
Mohamed Ghrici ◽  
Said Kenai
Keyword(s):  
Shear Strength ◽  
Internal Friction ◽  
Friction Angle ◽  
Internal Friction Angle ◽  
Plasticity Index ◽  
Engineering Properties ◽  
High Plasticity ◽  
Expansive Clay ◽  
Clayey Soils ◽  
Natural Pozzolana

Cohesive soils with a high plasticity index present difficulties in construction operations because they usually contain expansive clay minerals. However, the engineering properties of soils can be improved by different techniques. The aim of this paper is to study the effect of using lime, natural pozzolana or a combination of both lime and natural pozzolana on plasticity, compaction and shear strength of two clayey soils classified as CH and CL according to the unified soil classification system (USCS). The obtained results indicated that for CH class clay soil, the plasticity index decreased significantly for samples stabilized with lime. On the other hand, for the soil classified as CL class clay, a high decrease in the plasticity index value was observed for samples stabilized with natural pozzolana compared to those stabilized with lime. Also, both the cohesion and internal friction angle in lime added samples were demonstrated to increase with time. The combination of lime and natural pozzolana exhibits a significant effect on the enhancement of both the cohesion and  internal friction angle at later stages. The lime-natural pozzolana combination appears to produce higher shear strength parameters than lime or natural pozzolana used alone.

scholarly journals SEDIMENT DISTRIBUTION BASED ON GRAIN SIZE ANALYSES IN WEDA BAY, NORTHERN MALUKU

2014 ◽  
Vol 6 (1) ◽  
Author(s):  
Septriono Hari Nugroho ◽  
Abdul Basit
Keyword(s):  
Grain Size ◽  
Sediment Transport ◽  
Size Distribution ◽  
Deposition Process ◽  
General Information ◽  
Current Speed ◽  
Sediment Grain Size ◽  
Sediment Distribution ◽  
Sea Floor ◽  
Integrated Study

<p>An integrated study of sediment distribution was conducted in Weda Bay, Northern Maluku to provide general information on transportation and deposition process based on sediment grain size distribution. The study was conducted during the Weda Bay Expedition using the “Baruna Jaya VII” research vessel in March 13<sup>th</sup> –22<sup>th</sup> 2013. Sieving method (granulometric) was used to analyze the grain size. The results indicated that in general the pattern of sea floor sediment distribution was dominated by clay – sand grain-sized. The current speed influenced the sediment transport, deposition, and distribution.  Larger fractions of sediment were quickly settled on the sea floor due to stronger currents around Southern area (Widi islands), meanwhile the lesser fractions of the transported away into other places with weaker currents conditions.</p> <p>Keywords: current, the Weda Bay expedition, granulometric, grain size, sediment distribution</p>

scholarly journals ANALISIS DAYA DUKUNG PONDASI BORE PILE BERDASARKAN DATA SONDIR PADA PROYEK PEMBANGUNAN INSTALASI IBU KOTA KECAMATAN (IKK) PERUSAHAAN DAERAH AIR MINUM (PDAM) KABUPATEN TANAH LAUT

2020 ◽  
Vol 3 (2) ◽  
pp. 216
Author(s):  
Hendra Cahyadi ◽  
Akhmad Gazali ◽  
Firman Al Hakim
Keyword(s):  
Engineering Properties ◽  
Index Properties ◽  
Bore Pile

Penyelidikan geoteknik merupakan pekerjaan yang menghasilkan data - data penunjang dalam pekerjaan perencanaan suatu bangunan. Didalam kegiatan perencanaan, penyelidikan geoteknik harus dilakukan secara baik sehingga dihasilkan gambaran yang jelas mengenai index properties dan engineering properties dari tanah. Analisis geoteknik dilakukan untuk dapat mengetahui stabilitas dan daya dukung tanah dalam menerima beban struktur diatasnya. Untuk mengetahui struktur tanah dan daya dukung tanah di lokasi perencanaan proyek pembangunan Instalasi Ibu Kota Kecamatan (IKK) Pelaihari Perusahaan Daerah Air Minum Kabupaten Tanah Laut maka dilakukan analisis perhitungan daya dukung tanah menggunakan data sondir dari dua titik sondir dengan menggunakan tiga metode yaitu metode Van Der Ween, metode Philipponant, dan metode Mayerhoff. Berdasarkan hasil perhitungan nilai daya dukung pondasi bore pile dengan menggunakan tiga metode dihasilkan nilai daya dukung yang berbeda – beda. Untuk perhitungan menggunakan metode Van Der Ween hasil nilai daya dukung ultimit (Qult) 213.20 ton dengan daya dukung izin (Qizin) 71.06 ton untuk titik sondir S.02 dan 193.52 ton dengan daya dukung izin (Qizin) 64,50 ton untuk titik sondir S.03. Perhitungan menggunakan metode Philipponant   hasil nilai daya dukung ultimit (Qult) 136.51 ton dengan daya dukung izin (Qizin) 45,50 ton untuk titik sondir S.02 dan 135, 06 ton dengan daya dukung izin (Qizin) 45,02  ton untuk titik sondir S.03. Dan untuk perhitungan metode Mayerhoff hasil nilai daya dukung ultimit (Qult) 654.37 ton dengan daya dukung izin (Qizin) 218,12 ton untuk titik sondir S.02 dan 702.73 ton dengan daya dukung izin (Qizin) 234,24 ton untuk titik sondir S.03. Kata Kunci: sondir, daya dukung, Van Der Ween, Philipponant, Mayerhoff

scholarly journals Numerical simulation of extreme snow melt observed at the SIGMA-A site, northwest Greenland, during summer 2012

2015 ◽  
Vol 9 (1) ◽  
pp. 495-539
Author(s):  
M. Niwano ◽  
T. Aoki ◽  
S. Matoba ◽  
S. Yamaguchi ◽  
T. Tanikawa ◽  
...  
Keyword(s):  
Heat Flux ◽  
Grain Size ◽  
Latent Heat ◽  
Latent Heat Flux ◽  
In Situ Measurements ◽  
The Arctic ◽  
Snow Surface ◽  
Near Surface ◽  
Surface Snow

Abstract. The surface energy balance (SEB) from 30 June to 14 July 2012 at site SIGMA (Snow Impurity and Glacial Microbe effects on abrupt warming in the Arctic)-A, (78°03' N, 67°38' W; 1490 m a.s.l.) on the northwest Greenland Ice Sheet (GrIS) was investigated by using in situ atmospheric and snow measurements, as well as numerical modeling with a one-dimensional, multi-layered, physical snowpack model called SMAP (Snow Metamorphism and Albedo Process). At SIGMA-A, remarkable near-surface snowmelt and continuous heavy rainfall (accumulated precipitation between 10 and 14 July was estimated to be 100 mm) were observed after 10 July 2012. Application of the SMAP model to the GrIS snowpack was evaluated based on the snow temperature profile, snow surface temperature, surface snow grain size, and shortwave albedo, all of which the model simulated reasonably well. However, comparison of the SMAP-calculated surface snow grain size with in situ measurements during the period when surface hoar with small grain size was observed on-site revealed that it was necessary to input air temperature, relative humidity, and wind speed data from two heights to simulate the latent heat flux into the snow surface and subsequent surface hoar formation. The calculated latent heat flux was always directed away from the surface if data from only one height were input to the SMAP model, even if the value for roughness length of momentum was perturbed between the possible maximum and minimum values in numerical sensitivity tests. This result highlights the need to use two-level atmospheric profiles to obtain realistic latent heat flux. Using such profiles, we calculated the SEB at SIGMA-A from 30 June to 14 July 2012. Radiation-related fluxes were obtained from in situ measurements, whereas other fluxes were calculated with the SMAP model. By examining the components of the SEB, we determined that low-level clouds accompanied by a significant temperature increase played an important role in the melt event observed at SIGMA-A. These conditions induced a remarkable surface heating via cloud radiative forcing in the polar region.

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