scholarly journals Effect of Gypsum Content on CSAB Cement-Based Immobilization of Se and SO 4 from Industrial Filter Sludge and Sodium–Selenium Salts

2021 ◽  
Vol 25 (3) ◽  
Author(s):  
Katri Piekkari ◽  
Visa Isteri ◽  
Katja Ohenoja ◽  
Mirja Illikainen
Keyword(s):  
Gypsum Content

Influence of Limestone Powder on the Optimum Gypsum Content for Portland Cement with Different Alumina Content

2007 ◽  
Vol 18 (2) ◽  
pp. 103-113 ◽  
Author(s):  
Hiroki Yamashita ◽  
Kazuo Yamada ◽  
Hiroshi Hirao ◽  
Seiichi Hoshino
Keyword(s):  
Portland Cement ◽  
Limestone Powder ◽  
Alumina Content ◽  
Gypsum Content

scholarly journals Experimental Pullout Capacity of Screw Piles in Dry Gypseous Soil

2021 ◽  
Vol 318 ◽  
pp. 01002
Author(s):  
Mahdi O. Karkush ◽  
Omar J. Mukhlef
Keyword(s):  
Relative Density ◽  
Offshore Structures ◽  
Pullout Capacity ◽  
Single Screw ◽  
Gypsum Content ◽  
Pullout Testing ◽  
D 20 ◽  
Pile Model ◽  
Supporting Structures ◽  
Gypseous Soil

Screw piles are widely used in supporting structures subjected to pullout forces, such as power towers and offshore structures, and this research investigates their performance in gypseous soil of medium relative density. The bearing capacity and displacement of a single screw pile model inserted in gypseous soil with various diameters (D = 20, 30, and 40) mm are examined in this study. The soil used in the testing had a gypsum content of 40% and the bedding soil had a relative density of 40%. To simulate the pullout testing in the lab, a physical model was manufactured with specific dimensions. Three steel screw piles with helix diameters of 20, 30, and 40 mm are used, with a total length of 500 mm. The helix is continuous over the pile's embedded depth of 400 mm. The results of tests revealed that decreasing the length to diameter (H/D) ratio resulted in a higher pullout capacity of screw piles and a lower corresponding displacement.

scholarly journals Analysis of the data of hydrogeochemical monitoring of groundwater in the North Sivash artesian basin

2019 ◽  
pp. 64-71
Author(s):  
K. Ya. Bulakhova ◽  
S. M. Sudarikov
Keyword(s):  
Research Area ◽  
Geological Structure ◽  
Hydrogeological Model ◽  
Artesian Basin ◽  
Correlation And Regression Analysis ◽  
The North ◽  
Gypsum Content ◽  
Definition Of ◽  
Aquifer Complex ◽  
Made In

The results of hydrogeochemical monitoring of the Sarmat-Meotis-Pontic sediments aquifer complex of the North Sivash artesian basin have been analyzed. The analysis based on a routine observations for 16 producing wells. The observations were made in the period from 2014 to 2017 years. A correlation and regression analysis has been made for definition of dependencies between changes in the concentrations of the normalized components. The results obtained allow us to evaluate the main factors of formation of the chemical composition of groundwater. At the present stage, metamorphosed waters are pulled up from the lower strata of the complex, that leads to an increase in the amount of mineralization. The formation of sulphate waters is primarily associated with the peculiarities of the geological structure, namely, the high gypsum content of quaternary deposits and the presence of hydraulic connection with the overlying aquifers. One of the reasons for the formation of sulphate waters is the anthropogenic impact associated with the close location of the acid accumulator containing sulfur tailing. The results obtained allow us to proceed to the next stage of the survey — the creation of a natural hydrogeological model of the research area and the carrying of the thermodynamic modeling.

scholarly journals Dynamic Response of Single Pile Subjected to Different Frequencies in Gypseous Soil

2020 ◽  
Vol 13 (4) ◽  
pp. 50-57
Author(s):  
Noor D. Abd ◽  
Safa H. AbidAwn
Keyword(s):  
Experimental Study ◽  
Dynamic Response ◽  
Slenderness Ratio ◽  
Vibration Source ◽  
Single Pile ◽  
Collapsible Soil ◽  
Dynamic Movement ◽  
Steel Container ◽  
Gypsum Content ◽  
Gypseous Soil

This paper exhibits an experimental study on dynamic response of a single pile under dynamic load which comes from motor placed on cap pile called a vibration source. This study used the effect of the dynamic movement of vibration on one pile, collapsible soil (gypseous soil) used in this study with 30% gypsum content. The experiment is performed in a dry and soak state. A solid steel pile with a slenderness ratio of 27 was inserted into the soil after preparing it in layers in a steel container (30 * 30 * 60) cm. The test was performed under a dynamic response to the different frequencies 10, 15, 20, and 25 Hz. The results showed that the speed, acceleration and displacement increase with increasing frequency of the vibration source in addition to that the values of speed, acceleration and displacement amplitude are less in the case of soaking compared to their values in the dry state.

scholarly journals Effect of Pile Spacing on Group Efficiency in Gypseous Soil

2019 ◽  
Vol 5 (2) ◽  
pp. 373 ◽  
Author(s):  
Bilal Jabbar Noman ◽  
Safaa H. Abd-Awn ◽  
Hassan O. Abbas
Keyword(s):  
Bearing Capacity ◽  
Load Condition ◽  
Soil Mass ◽  
Deep Foundation ◽  
Collapsible Soil ◽  
Floating Pile ◽  
Group Efficiency ◽  
Gypsum Content ◽  
Group Pile ◽  
Gypseous Soil

As a matter of fact, the gypseous soil is usually considered as collapsible soil, such type of soil illustrates high resistance to settlement and high bearing capacity when it is dry, but it loses these characteristics when it is inundated and collapses excessively because of the sudden decrease in the volume of the surrounding soil mass. It is founded in the arid and semi-arid regions of the world in Asia, South Asia (Iraq, Syria, Jordan, Yemen, and Iran), North Africa, North America, moreover, it covers more than (31%) of the surface area in Iraq. Gypseous soil is one of the most difficult problems facing the process of building any project because of the difficulty of preventing leakage of water to the soil in practice. Deep foundation (piles) are one of the most common types used in collapsible soils which penetrating problematic soil layers and reaching more hard ones (end bearing piles) or transfers loads depending on skin friction (floating pile). The current work is directed to study the behavior of single and group driven pile of square pattern (4 piles) in case of floating pile (friction pile) with different spacing (2D, 4D, 6D) and length to diameter (L/D) ratio of (20) in this special medium dense soil (gypsum content 30% and 61%) under axial load condition. The investigation was carried out to measure the soil collapse before and after inundation. The results showed that the group efficiency for spacing 2D is less than one while for spacing 4D and 6D are more than that value. In addition, the spacing 4D was more efficient to carry 4 group pile in both dry and soaked cases, in addition, the result showed a high reduction in the bearing capacity at inundation state of group pile of (82% in gypsum content 30%) and ( 87% in gypsum content 61%) with respect to dry state.

scholarly journals Mineralogy of Gypsiferous Soil and the Effect of a dditiveLime Stone waste powder on its Physical Properties

2020 ◽  
pp. 83-91
Author(s):  
Thalar Othman Rashid ◽  
Nadhmia Najmaddin Majeed
Keyword(s):  
Grain Size ◽  
Specific Gravity ◽  
Soil Type ◽  
Soil Classification ◽  
Limestone Powder ◽  
Grain Size Analysis ◽  
Size Analysis ◽  
Atterberg Limit ◽  
Gypsum Content ◽  
Physical Testing

The presence of gypsum in soil as bonding agent alters its behavior with a large influence on itsphysical properties.Soil samples were taken from two locations of different gypsum content(S1 = 30.5% and S2= 20%) inMakhmur area. TheUnified soil classification system indicated that soil type was clay with low plasticity(CL). Basic methods of physical testing of soils, such as grain size analysis,specific gravity and atterberg limit were applied. Stabilizationof the gypsiferous soil was performed by addinglimestone waste powder takenfrom Said sadiqandPirmam areas,with different percentages(5%, 15%,25%).The results show that the addition of limestone powder to the tested soils decreases their liquid and plastic limits.

scholarly journals SIFAT FISIK DAN MEKANIK PAPAN GIPSUM DARI LIMBAH KAYU AKASIA (Acacia mangium Willd) BERDASARKAN KADAR GIPSUM DAN UKURAN SERBUK KAYU

2019 ◽  
Vol 7 (1) ◽  
Author(s):  
Ridho Pratama ◽  
M Dirhamsyah ◽  
. Nurhaida
Keyword(s):  
Mechanical Properties ◽  
Raw Materials ◽  
Acacia Mangium ◽  
Physical And Mechanical Properties ◽  
Powder Size ◽  
Wood Powder ◽  
Gypsum Board ◽  
Randomized Design ◽  
Gypsum Content ◽  
Two Factors

This study aims to examine the physical and mechanical properties of gypsum board from Acacia mangium Willd wood waste based on gypsum content and wood powder size. This study refers to the JIS A 5417-1992 standard. This research were conducted at Wood Work Shop laboratory for the preparation of raw materials, Wood Technology laboratory Faculty of Forestry for board making and testing the physical properties of gypsum boards, and  PT. Duta Pertiwi Nusantara laboratory to test the mechanical properties of the gypsum board. The material used is  A. mangium W. Wood powder, gypsum flour, water and borax. The study uses Factorial Completely Randomized Design (CRD) with two factors, namely factor A (gypsum content) which consists of gypsum content of 400%, 500% and 600% of the weight of A. mangium W. wood powder, and factors B (wood powder size) consists of 20 mesh passes 40 mesh retained and 40 mesh passes 60 mesh retained. The results showed that the density (600% gypsum content of 40 and 60 mesh retained wood powder size), moisture content, thickness swelling, MOE (600% gypsum content of 40 and 60 mesh retained wood powder size) fulfill JIS A5417-1992 standard. The best gypsum board is gypsum board with gypsum content of 600% with a wood powder size is 40 mesh.Keyword: Acacia mangium, gypsum board, gypsum content, wood powder size.

Obtaining Calcium Sulfoaluminate Using Aluminate Waste

2021 ◽  
Vol 1037 ◽  
pp. 743-750
Author(s):  
Ivan Y. Burlov ◽  
Dmitriy A. Zorin ◽  
Yury R. Krivoborodov
Keyword(s):  
Phase Analysis ◽  
Firing Temperature ◽  
Weak Dependence ◽  
Raw Material ◽  
High Quality ◽  
X Ray ◽  
Calcium Sulfoaluminate ◽  
Gypsum Content ◽  
Calcium Sulphoaluminate

In this work, studies have been carried out to replace bauxite with aluminate slags. Compounds of raw mixtures without use of fossil aluminate materials with different gypsum content have been developed. Instability of assimilation of anhydrite into calcium sulphoaluminate has been established. X-ray phase analysis has shown a weak dependence of increase in the firing temperature and increase in the yield of the main mineral C3A3·CŜ. Results of the study allow us to conclude that it is possible to obtain high-quality calcium sulphoaluminate (SAC) based on technogenic aluminate raw material.

scholarly journals Effect of gypsum content on unsaturated engineering properties of clayey soil

2020 ◽  
Vol 9 (1) ◽  
pp. 84
Author(s):  
Mohammed N J Alzaidy
Keyword(s):  
Shear Strength ◽  
Clayey Soil ◽  
Engineering Properties ◽  
Water Retention Curve ◽  
Shear Strength Parameters ◽  
Swelling Potential ◽  
Soil Water Retention Curve ◽  
Strength Parameters ◽  
Gypsum Content ◽  
Vapour Diffusion

Many of gypsum soils have existed in arid and semi-arid lands. It is considered one of the most problematic soils because of its complicated and unpredicted behavior when exposure to moisture. Extensive researches have been conducted in Iraq to observe the behavior of such soil and to suggest safety restrictions for the collapse and set practical precautions for the structures. This study investigated the effect of gypsum content on some unsaturated engineering properties of a clayey soil. Three different proportions of gypsum (0%, 5% and 20% by weight of the parent soil) were added and tested. The samples have been subjected to swelling potential test, soil water retention curve (SWRC), vapour diffusion and shear strength parameters. It is observed that gypsum content has a significant influence on SWRC, whereas, soil that has high gypsum content made SWRC with higher variables represented by air entry values and residual state. On the other hand, an increase in gypsum content led to a reduction of swelling potential and shear strength parameters. The results of vapour diffusion indicate that gypsum content could modify the microstructure in an unsaturated state and reduce the vapour diffusion through the soil.  

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