scholarly journals Development of CAGeD Observation Station and Its Impact on Coastal Process

2019 ◽  
Vol 8 (12) ◽  
pp. 3810-3815
Keyword(s):  
Specific Gravity ◽  
Research Work ◽  
High Tide ◽  
Current Speed ◽  
Environmental Research ◽  
Sieve Analysis ◽  
Silty Clay ◽  
Observation Station ◽  
Speed Test ◽  
Coastal Process

Universiti Tun Hussein Onn Malaysia (UTHM) collaboration with the Center of Applied Geomatics for Disaster Prevention (CAGeD) had developed an observation station as a catalyst for oceanographic and environmental research work and landmark of development in Tanjung Laboh. In conjunction with the construction of the station, monitoring of coastal process was carried out to identify the characteristics of sediment as input to the transportation of sediment around the construction area of the station in Tanjung Laboh. 20 points of surface sediment sampling were carried out along 200 meters of Tanjung Laboh bay during high tide. At the same time, the current speed test was carried out at the same point to identify the relationship of current speed to the transportation of sediment. All collected sediment samples have performed a test using wet sieve analysis (hydrometer), dry sieve analysis and specific gravity. The result found that the specific gravity of sediment at the study area is 2.53 and categorized as marine clay. The particle size distribution of sediment at the study area is silty clay due to the dominant of silt fraction. The percentage of sediment characteristics can be influenced by current velocity and sediment transportation.

Numerical Model of Current Speed in Bojong Salawe Beach, Pangandaran West Java Province

2021 ◽  
Vol 2 (1) ◽  
pp. 17-23
Author(s):  
Subiyanto Subiyanto ◽  
Nira na Nirwa ◽  
Yuniarti Yuniarti ◽  
Yudi Nurul Ihsan ◽  
Eddy Afrianto
Keyword(s):  
Numerical Models ◽  
High Tide ◽  
Movement Pattern ◽  
Numerical Data ◽  
Current Speed ◽  
The West ◽  
Instantaneous Speed ◽  
The Difference ◽  
West Monsoon ◽  
Current Movement

The purpose of this study was to determine the hydrodynamic conditions at Bojong Salawe beach. The method used in this research is a quantitative method, where numerical data is collected to support the formation of numerical models such as wind, bathymetry, and tide data. The hydrodynamic model will be made using Mike 21 with the Flow Model FM module to determine the current movement pattern based on the data used. In the west monsoon with a maximum instantaneous speed of 0.04 - 0.08 m/s, while in the east monsoon it moves with a maximum instantaneous speed of 0,4 – 0,44 m/s. The dominant direction of current movement tends to the northeast. The results indicate the current speed during the east monsoon is higher than the west monsoon. The difference in the current speed is also influenced by the tide conditions; higher during high tide and lower during low tide. Monsoons also have a role in the current movements, though the effect is not very significant.

scholarly journals An Overview of Surface Water Quality Influenced by Suspended Solid Content in the Sayung Waters, Demak, Indonesia

Jurnal Segara ◽  
2017 ◽  
Vol 13 (2) ◽  
Author(s):  
Ulung Jantama Wisha ◽  
Koko Ondara ◽  
Gunardi Kusumah
Keyword(s):  
High Tide ◽  
Surface Water Quality ◽  
Sampling Technique ◽  
Suspended Solid ◽  
Solid Content ◽  
Current Speed ◽  
Oxygen Cycle ◽  
Chemical Content ◽  
Fertile Area

Abrasion which is occurred in the Sayung coast is triggered by a big role of climate change as well as the sea level rise and land subsidence. Resulting degradation ultimately affects changes in existing environmental conditions. This study has aim to determine the existing water based on biological and chemical content which is affected by increasing suspended solid content in the Sayung waters. Purposive sampling technique was applied, and data is analyzed both statistically and spatially. Suspended solid value has ranged 23,1-199,6 mg/L. Distribution of suspended solid was only simulated during low tide towards high tide phase with current speed has ranged 0-0.41 m/s. We found that dissolved oxygen value is quite high in several observation stations which indicates the fertile area with low pollution and blooming tendency. In the station which is dominated by a high suspended solid and turbidity found that the chlorophyll-a decreases. The increased rate of suspended solid is directly enhancing the turbidity and indirectly declines the photosynthesis activity and inhibits the oxygen cycle. Resulting in the primary productivity reduction in the Sayung waters

scholarly journals The Effect of Addition of Bagasse Ash and Eggshell Powder on CBR Value of Clay Soil

2021 ◽  
Vol 926 (1) ◽  
pp. 012102
Author(s):  
M Carlina ◽  
Y Apriyanti ◽  
F Fahriani
Keyword(s):  
Specific Gravity ◽  
Moisture Content ◽  
Clay Soil ◽  
Road Construction ◽  
Soil Classification ◽  
Waste Materials ◽  
Sieve Analysis ◽  
Percentage Increase ◽  
Materials Used ◽  
Test Guideline

Abstract In the construction of road construction, soil bearing capacity, such as the CBR value, needs to be considered. In clay soil, the CBR value of the soil is low, so that stabilization material can be added to its repair. In this study, the stabilization materials used were waste materials in the form of bagasse ash and eggshell powder. Variations in the mixture of bagasse ash mixture used in this study were 7%, 10%, and 13% plus 3% eggshell powder. Testing in this study includes testing moisture content, sieve analysis, specific gravity, consistency limits, compaction testing, and CBR. The soil classification system used is the Unified classification (USCS), a test guideline based on SNI. From the CBR soaked test, it was found that the CBR value of clay soil increased along with the increase in the percentage of bagasse ash plus 3% eggshell powder and the increase in collisions on the soil. The percentage increase in the CBR value of clay soil with a mixture of stabilization to clay soil is 92.303%. at 65 blow. So that bagasse ash and eggshell powder greatly affect the increase in the CBR value of clay soil.

scholarly journals Assessment of Geotechnical Parameters of Lateritic Soil of Jos and Environs, for Civil Engineering Constructions North Central part of Nigeria

2020 ◽  
Vol 3 (3b) ◽  
pp. 222-239
Author(s):  
E Vincent ◽  
P Dominic ◽  
MM Kure
Keyword(s):  
Moisture Content ◽  
Civil Engineering ◽  
Biotite Granite ◽  
Engineering Properties ◽  
Dry Density ◽  
Sieve Analysis ◽  
Base Line ◽  
Silty Clay ◽  
Geotechnical Parameters ◽  
Engineering Construction

Due to failures of Civil Engineering structures in Jos and its Environs, Geotechnical parameters of Lateritic soils were carried out in order to determine its engineering properties for civil engineering construction. The methods involved are; reconnaissance survey, site works, laboratory tests based on British Standard (BS) methods and interpretation of the results. The laboratory test of the soils revealed that the Atterberg limit; Liquid limit (LL) ranged from 33.0% to 45.0%, Plastic limit (PL) from 16.23% to 26.37%, and Plasticity index (PI) from 8.63% to 22.67%. The percentage passing from the Sieve analysis ranges from 31.62% to 67.66%. The cohesive strength (c) and angle of internal friction (ø) from direct shear test ranged from 13KN/m2 to 24KN/m2 and 9° to 26°. The values of the Total settlement (Pc) from the Consolidation test ranged from 0.0005m to 0.0019m, Soil pH from 5.2 to 7.8, Specific gravity (SG) from 2.57 to 2.73 and Natural Moisture Content (NMC) from 8.18% to 46.36%. From the compaction test; the Optimum Moisture Content (OMC) ranged from 15.22% to 20.60% and Maximum Dry Density (MDD) from 1.62g/cm3 to 1.84g/cm3. The California Bearing Ratio (CBR) test for the soaked soils ranged from 21.0% to 93.0% and Un-soaked values from 50.75% to 96.61%. The findings reveal that; the geology of the area can be largely classified into granites (Biotite-microgranite, N’gell biotite-granite, Jos-biotite-granite and Aplo-pegmatitic granite-gneiss) and laterites. The geotechnical parameters of the soil are characteristically fair to poor, the strength and deformation of the soil reveals that it can mostly be used as a sub-base materials. The soil is classified as silty-clay, and the area need to be stabilized with cement, sand and gravel before carry civil engineering constructions. The results obtained will serve as base-line information for civil engineering construction in the study area in other to avoid structural damage.

Numerical Analysis of Slot Stability during the Supper-Deep Diaphragm Wall Construction

2013 ◽  
Vol 438-439 ◽  
pp. 1043-1047
Author(s):  
Bao Zhu Yang ◽  
Shu Chao Zhang ◽  
Kai Yun Luan
Keyword(s):  
Specific Gravity ◽  
Numerical Models ◽  
Silty Sand ◽  
Diaphragm Wall ◽  
Silty Clay ◽  
Soil Cement ◽  
Guide Wall ◽  
Wall Construction ◽  
Subway Stations ◽  
The Stability

Two subway stations of line Z1 were built in Tianjin cultural center and Tianjin Yujiapu traffic hub. The diaphragm wall depth of the two stations was more than 60 m. The geological and hydraulic conditions were different in the two site. Keeping stability of slot wall was the key of supper-deep diaphragm wall construction to the both stations. Two 3D numerical models were built by ABQUS software to simulate the grooving process. The conditions of different slurry specific gravity and grooving depth were calculated. The deformation laws of the slot wall and ground settlement around the slot wall were studied. The results showed the upper soft silty clay and deeper silty sand layers were easy collapse. Finally, some technologies such as "] [" type guide wall, properly improving slurry specific gravity, soil cement mixing reinforcement were suggested to improve the stability during the diaphragm wall construction of the two stations.

scholarly journals Characteristics of almond leaf-ash cement stabilized lateritic soil

2020 ◽  
Vol 39 (3) ◽  
pp. 701-709
Author(s):  
D.B. Eme ◽  
K.E. Ohwerhi
Keyword(s):  
Soil Sample ◽  
Lateritic Soil ◽  
Sieve Analysis ◽  
Silty Clay ◽  
Granulation Process ◽  
Stabilized Soil ◽  
Cement Stabilization ◽  
Verification Test ◽  
Cement Soil ◽  
Silty Clay Soil

The use of Almond leaf-ash for stabilization purposes has not been given consideration. This paper was thus aimed at evaluating the characteristics of almond leaf-ash for the essence of stabilizing lateritic soil. Sourced lateritic soil was divided into 3 components (unmodified soil sample, cement stabilized soil sample and almond leaf-ash cement stabilized soil sample). Almond leaves were calcined at 250°C and subjected to granulation process. Preliminary tests such as; sieve analysis, Atterberg’s limit and specific gravity tests were done on the unmodified soil sample for the purpose of classification. CBR tests were performed on the cement stabilized soil sample and on the almond leaf-ash cement stabilized lateritic soil sample. A model was developed using the Scheffe’s simplex theory with the cement component fixed at 10% of the dry lateritic soil. Results revealed that the soil was observed to be a Silty Clay soil (A-4) with Plasticity index of 9.24%, therefore requiring stabilization. CBR results for the developed trial mixes were greater than the 15.20% obtained for 10% cement stabilization showing that Almond leaf-ash significantly improved the CBR of the cement stabilized lateritic soil. The CBR model developed for the Almond leaf-ash cement soil also proved adequate from the verification test conducted using χ2 statistics. Keywords: Almond Leaf Ash, stabilization, California Bearing Ratio, Scheffe’s theory, lateritic soil.

scholarly journals Evaluating the effect of mud rheology and cuttings size on cuttings transportation in vertical wells

2020 ◽  
Vol 1 (1) ◽  
Keyword(s):  
Slip Velocity ◽  
Success Factors ◽  
Research Work ◽  
Sieve Analysis ◽  
Transport Parameters ◽  
Cuttings Transport ◽  
Vertical Wells ◽  
Test Models ◽  
Two Samples ◽  
Different Temperatures

As drilling optimization becomes the major concern of the drilling engineer and the mud specialist, there is therefore need to properly evaluate key success factors that ultimately affects the success of drilling operations. This research work examined the effects of fluid rheology and cuttings size on cuttings transportation in vertical wells. To achieve that, an experiment was conducted on two samples of fresh oil-based mud (A and B) of different rheology and two drilled cuttings sample (A and B) of sizes 400µm and 1000µm obtained from Anieze North field after sieve analysis. The drilled cuttings samples(A and B) were comingled with the mud(A and B) and their rheology (viscosity, density, plastic viscosity, yield point and gel strength) and cuttings transport parameters (slip velocity, transport velocity, transport ratio and transport efficiency) were checked at different temperatures. The cuttings transport parameters generated with the test models (Moore, Chien et al, and Zeidler) reveal that drilled cuttings of smaller size are easily transported than those of larger size. It was also observed that temperature has remarkable effects on rheology and slip velocity. Hence, slip velocity increases with temperature, while rheological values decrease with temperature. As a recommendation arising from the results of this investigation, a lower cuttings size should be ensured in a low viscous fluid for an efficient hole-cleaning. Apart from the aforementioned factors for efficient transportation of drilled cuttings, drilling bit configuration which is major determinant of the size of cuttings should be properly examined before selection for any drilling operation. Keywords: Cuttings Size, Cuttings Transport, Mud Rheology, Slip Velocity, Temperature

scholarly journals Weed study of mulched field in soil conservation technology

2019 ◽  
Vol 26 (01) ◽  
pp. 101-107
Author(s):  
Saikhantsetseg S ◽  
Baatartsol B ◽  
Nambar L
Keyword(s):  
Global Climate ◽  
Plant Cover ◽  
Research Work ◽  
Soil Surface ◽  
Environmental Research ◽  
Moisture Regime ◽  
Negative Consequences ◽  
Short Rotation ◽  
Humus Layer ◽  
Conservation Technology

Global climate change has been increasing year by year, and this change has become more intense  in our country. According to a study published by the Institute of Meteorology, Hydrology and  Environmental Research, the temperature has risen by 1.56 degrees over the last 60 years, with the change expected to rise by 1.99 degrees by 2020 and by 3.13 degrees by 2050. Mongolia has an extreme continental climate, and its’ plant cover is loose, soil humus layer is thinner, has mainly light mechanically compounded soil, low precipitation in winter, dryness in spring. On the other hand,  using a short rotation of grain fallow has created agro-ecological conditions such as vulnerable and a poorly-recovered environment. Under this situation, crop technologies need to be adapted to mitigate these negative consequences of the climate. Creating a large amount of plant covering will protect the soil from direct sunlight and its consequences. The final result of our research work is focused on identifying the changes of soil moisture regime of the covered area furthermore, the positive and negative impacts on the soil, decrease of weeds.  As a result of covering the soil surface with straw, temperature reduced by 2 degrees during the planting season, weeds grew 3.4 times less, the moisture of soil increased by 5.5 mm and plantlet of wheat seeds increased by 6.2 percent respectively. As an average of study years weed quantity at mulched variants was less by 14 pc/m2 and less weight 7.1 g/m2 than mulch less variants, this was increased weight of the main crop by 36.6 g/m2 and yield by 1.8 t/ha, respectively. Хөрс хамгаалах хучлагатай тариалангийн технологийн хог ургамлын судалгааны дүн Хураангуй:  Дэлхийн хэмжээнд уур амьсгалын өөрчлөлт эрчимжиж, жилээс жилд дулаарал нэмэгдэж,  энэхүү өөрчлөлт нь манай орны нөхцөлд бага хугацаанд илүү хүчтэй мэдрэгдэх боллоо. Ус цаг  уур, орчны судалгаа, мэдээллийн хүрээлэнгээс гаргасан судалгаагаар сүүлийн 60 жилийн  хугацаанд агаарын температур 1.56 хэмээр нэмэгдсэн, энэхүү өөрчлөлт цаашид үргэлжлэх  ба 2020 он гэхэд 1.99 хэм, 2050 онд 3.13 хэмээр нэмэгдэх төлөвтэй байгааг судлаачид  тогтоосон байна. Дулаарал нэмэгдэхийн хэрээр хөрсний чийгийн ууршилт нэмэгдэж,  бэлчээрийн болон таримал ургамлын чийг хангамж дутагдах, хур тунадасны хүртээмж  буурах нь зайлшгүй болно. Хур тунадас багатай, чийг хангалтгүй үед тариалангийн  технологи нь уур амьсгалын энэхүү сөрөг үр дагаварт дасан зохицсон, нөлөөллийг нь  бууруулахад чиглэх шаардлагатай бөгөөд бидний судалгааны үр дүн нь тариалангийн талбайд  ургамлын нөмрөг үүсгэснээр хөрсийг халалт цонолтоос хамгаалах, хучлага бүхий талбайн  хөрсний чийг дулааны горимын өөрчлөлт, сүрлэн хучлага хог ургамалд хэрхэн нөлөөлж буйг  илрүүлэв. Тариалангийн талбайн хөрсний гадаргууд 3 т сүрлэн хучлага үүсгэснээр хавар  тарилтын үед хөрсний үр суух гүний дулааныг 2 хэмээр бууруулж, хөрсний өнгөн 0-50 см гүний  чийгийг 5.5 мм-ээр нэмэгдүүлснээр буудайн үрийн соёололтыг 6.2 %-иар нэмэгдүүлж, хог  ургамал 3.4 дахин бага ургажээ. Хучлагатай талбайн цэцэглэлтийн үеийн хог ургамал 14  ш/м2-ээр, хог ургамлын жин 7.1 г/м2 -аар хучлагагүй хувилбараас бага байхад үндсэн  таримлын жин нь 36.6 г/м2-аар их байгаа нь 1.8 ц/га-аар ургацыг нэмэгдүүлэв. Түлхүүр үг: Сүрлэн хучлага,чийг, дулаан, ургац 

MAIN TRENDS OF THE SAMBIAN COASTAL SYSTEM (SOUTH-EASTERN BALTIC) DEVELOPMENT: HOLOCENE LITHODYNAMICS AND RECENT COASTAL PROCESSES

2017 ◽  
Author(s):  
Дарья Рябчук ◽  
Daria Ryabchuk ◽  
Alexander Sergeev ◽  
Alexander Sergeev ◽  
Vadim Sivkov ◽  
...  
Keyword(s):  
Coastal Zone ◽  
Sediment Traps ◽  
Silty Clay ◽  
Alluvial Deposits ◽  
Coastal System ◽  
Coastal Process ◽  
Russian Region ◽  
Storm Wave ◽  
Geophysical Study ◽  
Sedimentation Basins

Synthesis of long-term geological research on the Russian region of the southeastern Baltic and its coastal zone has allowed for the establishment of boundaries and determination of the time of formation and the structure of the Sambian morpho-lythodynamic marine and coastal system. The systems studied include the coastal zone (at a the water depth of 30 m according to longshore storm wave current impacts) and adjacent silty-clay sedimentation basins. The development of the Curonian Spit area in the Late Pleistocene – Holocene was reconstructed based on marine geological and geophysical study and modelling. Comparative analyses of the geological settings of the Curonian and Vistula Spits and lagoons has shown that the mechanisms for their development are significantly different. By the late Holocene, the southeastern Baltic Sea consisted of several lithodynamic coastal systems. By 5 ka BP, both lagoon systems had formed. Evolution of the spits and lagoons during the last 5000 years caused the development of similar morphological features. The Vistula and Curonian lagoons transformed into sediment traps for alluvial deposits of the Neman and Pregola Rivers. Smoothing of the shoreline as a result of longshore sediment drift is a dominant coastal process.

scholarly journals A study of the fish community structure in a tidal creek

2004 ◽  
Vol 64 (2) ◽  
pp. 337-351 ◽  
Author(s):  
H. L. Spach ◽  
C. Santos ◽  
R. S. Godefroid ◽  
M. Nardi ◽  
F. Cunha
Keyword(s):  
Community Structure ◽  
Environmental Factors ◽  
Fish Community ◽  
Tidal Creek ◽  
High Tide ◽  
Current Speed ◽  
Water Transparency ◽  
Fish Community Structure ◽  
Total Capture ◽  
Biological Patterns

The fish assemblage in a mangrove tidal creek was studied in monthly collections between August 1998 and July 1999 in the quadrature low tide and high tide, using a fyke net of 30 m x 1.5 m and meshes of 8 and 10 mm. Simultaneously with the biological collections, temperature, salinity, pH, water transparency, and current speed data were obtained. The collections resulted in the capture of 36,873 fish representing 22 families and 52 species. Immature individuals abounded (63.8%), and among the adult specimens there was a larger number of females. The species Anchoa parva, Harengula clupeola, Genidens genidens, and Bairdiella ronchus, contributed to 84.9% of the total capture of fish, however the contribution in mass was of 55.2%, indicating a predominance of small individuals. A smaller number of fish and species seem to occupy the area in the period between August and December, in comparison to the period between February and July, when the larger aggregations appear, mainly of the species Anchoa parva, Harengula clupeola, Opisthonema oglinum, Genidens genidens, Diapterus rhombeus, and Bairdiella ronchus. The environmental factors, pH, water transparency, and rainfall seem to have an influence in the structure of the observed biological patterns.

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