scholarly journals IMPLEMENTATION OF FELDSPAR AS PARTIALLY REPLACEMENT MATERIAL IN CEMENT MORTAR (EXPLORATION AND APPLICATION)

2021 ◽  
pp. 1-9
Author(s):  
Walid Edris ◽  
Mahmoud Al-Tamimi ◽  
Mohammed Aldelgawy
Keyword(s):  
Compressive Strength ◽  
Elevated Temperatures ◽  
Cement Mortar ◽  
Setting Time ◽  
Raw Material ◽  
Replacement Ratio ◽  
Cement Replacement ◽  
Residual Compressive Strength ◽  
Setting Times ◽  
Compressive And Flexural Strengths

This paper aims to explore and evaluate the use of Jordanian Feldspar as a natural resource partially replacement material for each of cement and sand in cement mortar. First, Al-Jaishia area was explored through a global positioning system (GPS) navigation to gather site samples of Feldspar raw material. Afterward, cement and sand were partially replaced by Feldspar with substitution ratios of 5%, 10%, 15%, 20%, and 25% for each. The study included the effect of cement replacement on normal consistency and setting time for cement paste. The water content along with initial and final setting times increased via the increment of cement replacement ratio. Moreover, mechanical properties (compressive, flexural, and residual compressive strengths) of cement mortar due to both cement and sand replacement were evaluated. The compressive and flexural strengths after 3, 7, and 28 days of curing were examined for both cement and sand replacement. While, residual compressive strength for cement replacement after 28 days was measured at elevated temperatures of 400°C, 600°C, and 800°C. The compressive and flexural strengths decreased by increasing the Feldspar replacement ratio for both cement and sand at all specimen ages. Whereas, heat resistance properties were improved by cement/Feldspar replacement. The best result for residual compressive strength was obtained at 15% replacement ratio and 400°C temperature.

scholarly journals Influence of a Retarding Admixture on the Behavior of Mortars Made from Different Types of Cement

2018 ◽  
Vol 7 (4.20) ◽  
pp. 334
Author(s):  
Tumadhir Merawi Borhan ◽  
Munaf A. Al-Ramahee ◽  
Noor Al-Hassnawi ◽  
Zaid Ali AlZaidi
Keyword(s):  
Compressive Strength ◽  
Portland Cement ◽  
Cement Mortar ◽  
Setting Time ◽  
Length Change ◽  
Setting Times ◽  
White Cement ◽  
Cement Mortars ◽  
Different Types ◽  
Positive Effect

The effect of retarding admixture on the fresh and hardened behaviour of different types of cement mortars and pastes when using a retarding admixture was investigated in this study. The types of cement used are; White cement (WhC), Ordinary Portland cement (OPC) and Sulphate Resistant Portland cement (SRC). Different cement mortar and paste mixes were cast, for this purpose, with and without the admixture. Initial and final setting times, compressive strength, length change, absorption and density for these mixes were examined at the curing ages of 3,7,28,45 days. The results showed that the addition of retarding admixture delayed the setting time significantly of WhC paste. The retarding admixture has a positive effect on the compressive strength of the mortar specimens for all types of cement used. regarding the length change test, the admixture was found to reduce the initial expansion for all types of cement at all ages. The results also showed an increase in the density and decrease in water absorption, especially at the later ages for all types of cement.  Among all cement types used, WhC was noticeably the most affected type by using the retarding admixture compared to other types of cement used.  

scholarly journals Characteristics of Wood Ash Cement Mortar Incorporating Green-Synthesized Nano-TiO2

2021 ◽  
Vol 15 (1) ◽  
Author(s):  
Bolanle Deborah Ikotun ◽  
Akeem Ayinde Raheem
Keyword(s):  
Compressive Strength ◽  
Water Absorption ◽  
Cement Mortar ◽  
Setting Time ◽  
Wood Ash ◽  
Partial Replacement ◽  
Nano Tio2 ◽  
Setting Times ◽  
Binder Ratio ◽  
Water To Binder Ratio

AbstractThis paper presents the findings of an investigation into the influence of green-synthesized nano-TiO2 on the characteristics of wood ash (WA) cement mortar. Mortar specimens were prepared by partial replacement of cement with WA (10% by weight) and addition of 1, 2 and 3% nano-TiO2 by weight of binder; using constant water-to-binder ratio (w/b) for all mixtures. The properties evaluated are setting time of the binder and flexural and compressive strength with water absorption of the mortar. The results indicated that addition of 1 and 2% nano-TiO2 reduced setting times of WA cement paste. Also, the flexural and compressive strength of WA cement mortar were higher with the incorporation of up to 2% nano-TiO2. The water absorption of WA cement mortar was reduced when nano-TiO2 was added with 2% incorporation having the best result. The incorporation of NT in WA cement mortar improved its workability and strength characteristics.

scholarly journals Influence of α-Calcium Sulfate Hemihydrate on Setting, Compressive Strength, and Shrinkage Strain of Cement Mortar

Materials ◽  
2019 ◽  
Vol 12 (1) ◽  
pp. 163 ◽  
Author(s):  
Bokyeong Lee ◽  
Gyuyong Kim ◽  
Jeongsoo Nam ◽  
Kyehyouk Lee ◽  
Gyeongtae Kim ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Calcium Sulfate ◽  
Cement Mortar ◽  
Setting Time ◽  
Shrinkage Strain ◽  
Replacement Ratio ◽  
Initial Setting Time ◽  
Initial Setting ◽  
Furnace Slag ◽  
Calcium Sulfate Hemihydrate

This study focused on the quick initial setting time and the expansion strain that occurs during the early aging of α-calcium sulfate hemihydrate (αHH) and examined the setting, compressive strength, and shrinkage strain of αHH-replaced cement mortar. The results show that the initial setting time significantly decreased with an increase in the αHH replacement ratio. Drastic occurrence of ettringite was observed early in the aging of cement mortar when αHH was substituted into the cement; however, the ettringite was not converted to monosulfate with increasing age and thus was not favorable for the development of the compressive strength. When αHH was substituted into cement, using Portland blast-furnace slag cement (PSC) was more advantageous than using ordinary Portland cement (OPC) for the development of the compressive strength. Meanwhile, the expansion of early age αHH can decrease the shrinkage strain of cement mortar. The generation of ettringite is more effective when αHH is substituted into PSC than into OPC and is thus more effective in suppressing the shrinkage strain.

ON THE USE OF SLAG CEMENT COMPOSITIONS IN THE CONSTRUCTION OF WELLS

2017 ◽  
pp. 80-85
Author(s):  
V. P. Ovchinnikov ◽  
O. V. Rozhkova ◽  
N. A. Aksenova ◽  
P. V. Ovchinnikov
Keyword(s):  
Blast Furnace ◽  
Blast Furnace Slag ◽  
Elevated Temperatures ◽  
Cement Mortar ◽  
Setting Time ◽  
Rheological Parameters ◽  
Slag Cement ◽  
Furnace Slag

In the article studies of oil-filled compositions with the addition of blast-furnace slag for strength at elevated temperatures are presented. The rheological parameters of the slag cement slag cement mortar, as well as the setting time, were studied. Conclusions are drawn about the prospects of further study of slag cementcontaining compositions.

Effects of Elevated Temperatures on the Compressive Strength of HFCC

2011 ◽  
Vol 261-263 ◽  
pp. 416-420 ◽  
Author(s):  
Fu Ping Jia ◽  
Heng Lin Lv ◽  
Yi Bing Sun ◽  
Bu Yu Cao ◽  
Shi Ning Ding
Keyword(s):  
Compressive Strength ◽  
Elevated Temperature ◽  
Fly Ash ◽  
Room Temperature ◽  
Elevated Temperatures ◽  
Relative Strength ◽  
Ordinary Concrete ◽  
Residual Compressive Strength ◽  
Fly Ash Concrete ◽  
The Relationship

This paper presents the results of elevated temperatures on the compressive of high fly ash content concrete (HFCC). The specimens were prepared with three different replacements of cement by fly ash 30%, 40% and 50% by mass and the residual compressive strength was tested after exposure to elevated temperature 250, 450, 550 and 650°C and room temperature respectively. The results showed that the compressive strength apparently decreased with the elevated temperature increased. The presence of fly ash was effective for improvement of the relative strength, which was the ratio of residual compressive strength after exposure to elevated temperature and ordinary concrete. The relative compressive strength of fly ash concrete was higher than those of ordinary concrete. Based on the experiments results, the alternating simulation formula to determine the relationship among relative strength, elevated temperature and fly ash replacement is developed by using regression of results, which provides the theoretical basis for the evaluation and repair of HFCC after elevated temperature.

Isothermal Fatigue Behavior and Damage Modeling of a High Temperature Woven PMC

1999 ◽  
Vol 122 (1) ◽  
pp. 62-68 ◽  
Author(s):  
A. L. Gyekenyesi
Keyword(s):  
Compressive Strength ◽  
Elevated Temperature ◽  
Elevated Temperatures ◽  
Fatigue Behavior ◽  
Stiffness Degradation ◽  
Fatigue Properties ◽  
Residual Compressive Strength ◽  
Stiffness Reduction ◽  
Fatigue Damage Accumulation ◽  
Strength Tests

This study focuses on the fully reversed fatigue behavior exhibited by a carbon fiber/polyimide resin woven laminate at room and elevated temperatures. Nondestructive video edge view microscopy and destructive sectioning techniques were used to study the microscopic damage mechanisms that evolved. The elastic stiffness was monitored and recorded throughout the fatigue life of the coupon. In addition, residual compressive strength tests were conducted on fatigue coupons with various degrees of damage as quantified by stiffness reduction. Experimental results indicated that the monotonic tensile properties were only minimally influenced by temperature, while the monotonic compressive and fully reversed fatigue properties displayed greater reductions due to the elevated temperature. The stiffness degradation, as a function of cycles, consisted of three stages; a short-lived high degradation period, a constant degradation rate segment covering the majority of the life, and a final stage demonstrating an increasing rate of degradation up to failure. Concerning the residual compressive strength tests at room and elevated temperatures, the elevated temperature coupons appeared much more sensitive to damage. At elevated temperatures, coupons experienced a much larger loss in compressive strength when compared to room temperature coupons with equivalent damage. The fatigue damage accumulation law proposed for the model incorporates a scalar representation for damage, but admits a multiaxial, anisotropic evolutionary law. The model predicts the current damage (as quantified by residual stiffness) and remnant life of a composite that has undergone a known load at temperature. The damage/life model is dependent on the applied multiaxial stress state as well as temperature. Comparisons between the model and data showed good predictive capabilities concerning stiffness degradation and cycles to failure. [S0742-4795(00)01001-2]

scholarly journals Effect of Waste Clay Brick Powder on Physical and Mechanical Properties of Cement Paste

2021 ◽  
Vol 15 (1) ◽  
pp. 370-380
Author(s):  
David Sinkhonde ◽  
Richard Ocharo Onchiri ◽  
Walter Odhiambo Oyawa ◽  
John Nyiro Mwero
Keyword(s):  
Compressive Strength ◽  
Cement Paste ◽  
Setting Time ◽  
Partial Replacement ◽  
Clay Brick ◽  
X Ray ◽  
Cement Replacement ◽  
Clay Bricks ◽  
Brick Powder ◽  
Scanning Electron

Background: Investigations on the use of waste clay brick powder in concrete have been extensively conducted, but the analysis of waste clay brick powder effects on cement paste is limited. Materials and Methods: This paper discusses the effects of waste clay brick powder on cement paste. Fragmented clay bricks were grounded in the laboratory using a ball mill and incorporated into cementitious mixes as partial replacement of Ordinary Portland Cement. Workability, consistency, setting time, density and compressive strength properties of paste mixes were investigated to better understand the impact of waste clay brick powder on the cementitious paste. Four cement replacement levels of 2.5%, 5%, 7.5% and 10% were evaluated in comparison with the control paste. The chemical and mineral compositions were evaluated using X-Ray Fluorescence and X-Ray Diffractometer, respectively. The morphology of cement and waste clay brick powder was examined using a scanning electron microscope. Results: The investigation of workability exhibited a reduction of slump attributed to the significant addition of waste clay brick powder into the cementitious mixes, and it was concluded that waste clay brick powder did not significantly influence the density of the mixes. In comparison with the control paste, increased values of consistency and setting time of cement paste containing waste clay brick powder confirmed the information available in the literature. Conclusion: Although waste clay brick powder decreased the compressive strength of cement paste, 5% partial cement replacement with waste clay brick powder was established as an optimum percentage for specimens containing waste clay brick powder following curing periods of 7 and 28 days. Findings of chemical composition, mineral composition and scanning electron microscopy of waste clay brick powder demonstrated that when finely ground, fragmented clay bricks can be used in concrete as a pozzolanic material.

Behaviour of Calcium Alkali Orthophosphate Cements under Simulated Implantation Conditions

2008 ◽  
Vol 396-398 ◽  
pp. 213-216 ◽  
Author(s):  
Daniela Jörn ◽  
Renate Gildenhaar ◽  
Georg Berger ◽  
Michael Stiller ◽  
Christine Knabe
Keyword(s):  
Compressive Strength ◽  
Simulated Body Fluid ◽  
Clinical Application ◽  
Body Fluid ◽  
Setting Time ◽  
Great Decrease ◽  
Final Setting Time ◽  
Laboratory Conditions ◽  
Setting Times

The setting behaviour, the compressive strength and the porosity of four calcium alkali orthophosphate cements were examined under laboratory conditions (dry) and under conditions similar to those during clinical application (37°C, contact with body fluid). The results showed an increase of the setting times when specimens were covered with simulated body fluid. Especially, the final setting time (FHZ) was significantly higher for three of the four cements. Furthermore, when specimens were stored in SBF for 16h, an extensive decrease of the compressive strength was noted. The porosity was more than twice as high after 16h in SBF and this may be the cause for the great decrease of the compressive strength.

Setting Time and Compressive Strength of Mortar Containing Cockle Shell Powder as Partial Cement Replacement

2021 ◽  
Vol 879 ◽  
pp. 62-67
Author(s):  
Khairunisa Muthusamy ◽  
Rahimah Embong ◽  
Nabilla Mohamad ◽  
Nur Syahira Hanim Kamarul Bahrin ◽  
Fadzil Mat Yahaya
Keyword(s):  
Compressive Strength ◽  
Setting Time ◽  
Cement Replacement ◽  
Compressive Strength Test ◽  
Shell Waste ◽  
Suitable Combination ◽  
Time Test ◽  
Partial Cement Replacement ◽  
Shell Powder ◽  
Cockle Shell

Environmental degradation caused by deforestation activities for harvesting of limestone from the hills and its calcination process at cement factory along with disposal of cockle shell waste from fisheries industries is in need of resolution. In view of sustainable green environment, approach of utilizing cockle shell waste as partial cement replacement in cement production would reduce pollution caused by both industries. Thus, this research investigates the effect of cockle shell powder as partial cement replacement on setting time and compressive strength of mortar. A total of five types of mortar mixes consisting different percentage of cockle shell powder as partial cement replacement from 0%, 10%, 20%, 30%, and 40% by weight of cement were prepared. Setting time test were conducted on fresh paste. All specimens were subjected to water curing until the testing age. Compressive strength test were conducted on hardened mortar cubes at 3, 7 and 28 days. Finding shows that integration of cockle shell powder as partial cement replacement influences the setting time and compressive strength of mortar. Suitable combination of 10% cockle shell powder successfully enhances the compressive strength of mortar. Conclusively, success in transforming the cockle shell waste to be used as partial cement replacement in mortar production able to reduce cement consumption, save landfill usage for trash dumping and promote cleaner environment for healthier lifestyle of community nearby.

Studies on Exciting the Activity of Waste Glass Powder by Hydrothermal Activation

2013 ◽  
Vol 871 ◽  
pp. 171-178
Author(s):  
Qing Qiu Kong ◽  
Guo Jun Ke ◽  
Dan Wang
Keyword(s):  
Compressive Strength ◽  
Hydrothermal Treatment ◽  
Glass Powder ◽  
Cement Mortar ◽  
Waste Glass ◽  
Early Age ◽  
Cement Replacement ◽  
Waste Glass Powder ◽  
Temperature And Pressure ◽  
Optimal Strength

The effect of hydrothermal activation indifferent temperature and pressure conditions on the pozzolanic activity of waste glass powder was discussed. The waste glass powder was treated at 108°C, 0.15MPa, 116°C, 0.18MPa and 121°C, 0.2MPa for 2h in an autoclave respectively after milling to 4215cm2/g. Mortar was made with untreated and hydrothermal activated waste glass power replacement of cement at 20% respectively, then tested for compressive strength at 3, 7, 14 , 28 and 90 days. Results showed that compressive strength of cement mortar had varying degrees of decline when replacing cement with untreated waste glass powder, comparing to the control one. Decline amplitude was large at early age and small at late age. Activity of waste glass powder was significantly improved after hydrothermal treatment. Compressive strength of mortar improved as temperature and pressure elevated, obtaining optimal strength at 121°C, 0.2MPa. Compressive strength of mortar with hydrothermal activated glass powder was higher than that with untreated glass powder at all age with 20% cement replacement. Compressive strength increased 5.3% ~ 13.6% at 3 d, 6.8%~9.7% at 28 d, 9.7% ~ 17.7% at 90 d. The essence of hydrothermal activation was the corrosion of water in the glass.

Sign in / Sign up

Export Citation Format

Share Document