Effects of Fresh Concrete Temperature and Mixing Time on Compressive Strength of Concrete

2001 ◽  
Vol 98 (1) ◽  
Keyword(s):  
Compressive Strength ◽  
Fresh Concrete ◽  
Mixing Time ◽  
Concrete Temperature ◽  
Compressive Strength Of Concrete

scholarly journals Effect of Water Cement Ratios on Compressive Strength of Palm Kernel Shell Concrete

2019 ◽  
Vol 2 (Issue 1) ◽  
Author(s):  
A.O Adeyemi ◽  
M.A Anifowose ◽  
I.O Amototo ◽  
S.A Adebara ◽  
M.Y Olawuyi
Keyword(s):  
Compressive Strength ◽  
Coarse Aggregate ◽  
Fresh Concrete ◽  
Palm Kernel ◽  
Hardened Concrete ◽  
Cement Ratio ◽  
Water Cement Ratio ◽  
Palm Kernel Shell ◽  
Compressive Strength Of Concrete ◽  
Palm Kernel Shells

This study examined the effect of varying water cement ratio on the compressive strength of concrete produced using palm kernel shell (PKS) as coarse aggregate at different replacement levels. The replacement levels of coarse aggregate with palm kernel shells (PKS) were 0%, 25%, 50%, and 100% respectively. PKS concrete cubes (144 specimens) of sizes 150mm x 150mm x 150mm were cast and cured in water for 7, 14, 21 and 28 days respectively. A mix ratio of 1:2:4 was adopted with water-cement ratio of 0.45, 0.5, and 0.6 respectively while the batching was done by weight. Slump test was conducted on fresh concrete while compressive strength test was carried out on the hardened concrete cubes using a compression testing machine of 2000kN capacity. The result of tests on fresh concrete shows that the slump height of 0.45 water cement ratio (w/c) increases with an increase in PKS%. This trend was similar to 0.50 and 0.60 w/c. However, the compressive strength of concrete cube decreases with an increase in w/c (from 0.45 to 0.60) but increases with respect to curing age and also decreases with increase in PKS%. Concrete with 0.45 water-cement ratio possess the highest compressive strength. It was observed that PKS is not a good substitute for coarse aggregate in mix ratio 1:2:4 for concrete productions. Hence, the study suggest the use of chemical admixture such as superplasticizer or calcium chloride in order to improve the strength of palm kernel shells-concrete.

scholarly journals Effect of Tile Powder Used as a Cementitious Material on the Mechanical Properties of Concrete

2019 ◽  
Vol 9 (5) ◽  
pp. 4596-4599 ◽  
Author(s):  
N. Bheel ◽  
R. A. Abbasi ◽  
S. Sohu ◽  
S. A. Abbasi ◽  
A. W. Abro ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Compressive Strength ◽  
Fresh Concrete ◽  
Cementitious Material ◽  
Splitting Tensile Strength ◽  
Hardened Concrete ◽  
Compressive Strength Of Concrete ◽  
Powder Content ◽  
Cylindrical Samples

This study was undertaken to reduce the usage of cement in concrete where different proportions of tile powder as cement replacement were used. Since in the manufacture of cement an exuberant amount of carbon dioxide is disposed of in the environment, this research aims to curtail the dependence on cement and its production. The objective of this work is to investigate the properties of fresh mix concrete (workability) and hardened concrete (compressive and splitting tensile strength) in concrete with different proportions of 0%, 10%, 20%, 30%, and 40% of tile powder as a cement substitute. In this study, a total of 90 concrete samples were cast with mix proportions of 1:1.5:3, 0.5 water-cement ratio, cured for 7, 14 and 28 days. For determining the compressive strength, cubical samples, with dimensions of 100mm×100mm×100mm, were cast, while for the determination of the splitting tensile strength, cylindrical samples with dimensions of 200mm diameter and 100mm height, were tested after 7, 14, and 28 days. The highest compressive strength of concrete achieved for tile powder concrete was 7.50% at 10% replacement after 28days of curing. The splitting tensile strength got to 10.2% when concrete was replaced with 10% of tile powder and cured for 28 days. It was also shown that with increasing percentage of the tile powder content, the workability of the fresh concrete increases.

scholarly journals Effect of R.O. Waste Water on Properties of Concrete

2019 ◽  
Vol 8 (3) ◽  
pp. 2806-2808
Keyword(s):  
Waste Water ◽  
Compressive Strength ◽  
Reverse Osmosis ◽  
Potable Water ◽  
Fresh Concrete ◽  
Test Results ◽  
Normal Concrete ◽  
Experimental Procedure ◽  
Compressive Strength Of Concrete

This paper concentrates on preparing concrete in which reverse osmosis waste water is incorporated in mixing and to cure. Experimental procedure consists of 4 mix proportions of various water cement ratios. Fresh concrete is tested for workability and flowing ability. Cubes were casted and tested to find out compressive strength of concrete. Test results of potable water concrete and RO waste water concrete were compared. Results show that workability of both the concretes is almost same. When coming to the compressive strength, RO waste water concrete shows less strength at 28days compared to normal concrete.

The Research of Mud Influence on Properties of Concrete

2014 ◽  
Vol 629-630 ◽  
pp. 462-466
Author(s):  
Mei Yan Hang ◽  
Ying Jing Lan ◽  
Pei Yu Zhang ◽  
Li Ming Zhang
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Fresh Concrete ◽  
Hardened Concrete ◽  
Mixture Ratio ◽  
Compressive Strength Of Concrete

Abstract: The same amount of mixture ratio of cement, replacing a part of fly ash with a certain amount of mud to research about the workability of fresh concrete and the effect of the mechanical and shrinkage properties of hardened concrete. Test's results show: The different kinds of mud lead that the fluidity of the fresh concrete and the strength of hardened concrete are different. The influence of sand mud is lighter than planting mud on the fluidity and strength of concrete. The compressive strength of concrete decreases and the early shrinkage increase with an increase of mud replaced the fly ash.

scholarly journals Effect of Dolomite as Expansive Agent and Shrinkage Reducing Admixture in Self-Compacting Shrinkage – Compensating Concrete

2018 ◽  
Vol 26 (5) ◽  
pp. 1-8
Author(s):  
Qosai Sahib Radi Marshdi ◽  
Ahlam Hamid Jasim ◽  
Haider Abass Obeed
Keyword(s):  
Compressive Strength ◽  
Fresh Concrete ◽  
Drying Shrinkage ◽  
The Other ◽  
Restrained Shrinkage ◽  
Fresh Properties ◽  
Expansive Agent ◽  
Concrete Mixtures ◽  
Shrinkage Reducing Admixture ◽  
Compressive Strength Of Concrete

The principle of using expansive agents has been recommended to manufacture shrinkage compensating concrete provided that an adequate wet curing is carried out. On the other hand, shrinkage-reducing admixture (SRA) in the concrete mixes, has been more recently suggested to reduce the risk of cracking in concrete structures caused by drying shrinkage. This paper is devoted to the study of the influence of complex modifier in the form of superplasticizer, shrinkage reducing admixture and expansive agent CaO- MgO-based on the fresh properties, hardening processand restrained shrinkage of Self-Compacting-Shrinkage-Compensating Concretes. The combined addition of shrinkage-reducing admixture with expansive agent has been found to be successful in producing shrinkage-compensating concrete. It should be noted also that the shrinkage reducing admixture slightly improve the workabilityof the fresh concrete mixtures but, it slightly reduces the early compressive strength of concrete.

Experimental Study on Gap-Graded Concrete Mixing Uniformity

2013 ◽  
Vol 857 ◽  
pp. 42-50
Author(s):  
Hai Peng Gao ◽  
Bo Tian ◽  
Zi Yi Hou
Keyword(s):  
Experimental Study ◽  
Compressive Strength ◽  
Relative Error ◽  
Unit Volume ◽  
Coarse Aggregate ◽  
Mixing Time ◽  
Mixing Process ◽  
Stirring Time ◽  
Compressive Strength Of Concrete

Combining with the concrete mixing process of twin-shaft mixer, this paper studied the gap-graded concrete mixing uniformity variation under different time. The study found that: under different mixing time, the relative error of coarse aggregate weight in per unit volume decreases, the compressive strength of concrete specimens change from increase to decrease, and they respectively reach the minimum and maximum at 40s, according to this, we get to optimum stirring time is 30~40s; Torque can reflect the condition of concrete mixing to a certain extent, but when the torque becomes stable, it does not stand for the uniformity of concrete mixing, keep stirring about 8s, the concrete mixing will be uniform completely.

scholarly journals ANALISA PENGARUH ADMIXTURE TERHADAP ABU TERBANG (FLY ASH) DAN BOTTOM ASH

2018 ◽  
Vol 6 (2) ◽  
pp. 114-123
Author(s):  
Redaksi Tim Jurnal
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Silica Fume ◽  
Fresh Concrete ◽  
Setting Time ◽  
Bottom Ash ◽  
Initial Time ◽  
Concrete Compressive Strength ◽  
Concrete Temperature ◽  
Concrete Quality

With improve the quality of concrete is by using the addition of admixture. By adding admixture Silica fume and superplasticizer is expected to improve concrete quality in concrete using fly ash and bottom ash. The main objective of this research is to know the value of concrete compressive strength, slump test value, fresh concrete temperature and setting time in concrete using fly ash and bottom ash by 0%, 5%, 10%, 15%, 20% and 25% by weight of cement, with variations of silica fume 0%, 2%, 4%, 6 %, 8%, 10% of the weight of cement that has been reduced by the weight of fly ash and bottom ash and added with superplasticizer of 2% of the water requirement. The planned concrete quality was 41.7 MPa at 28 days, with the sample tested at age 7, 14, 28 days. Based on the results of the highest concrete compressive strength test for fly ash concrete (fly ash) is found in FA mixture variation 10%, SP 4%, SF 2% that is equal to 56,16 MPa. And for mixed bottom ash the highest compressive strength on mixed variation of BA 5%, SF 2%, SP 2% is equal to 49,82 MPa. Fresh concrete temperature variation of FA mixture 5%, SF 2%, SP 2% and BA 5%, SF 2%, SP 2% rose one degree from normal concrete temperature. Setting time generated on mixed concrete FA 5%, SF 2%, SP 2% has the fastest initial time setting ie 251 minutes of all variations of concrete mix.

scholarly journals Experimental study on the influence of mixing time on concrete performance under different mixing modes

2021 ◽  
Vol 28 (1) ◽  
pp. 638-651
Author(s):  
Wu Zhao ◽  
Jing Yang ◽  
Wenjun Zhao ◽  
Chi Yang
Keyword(s):  
Compressive Strength ◽  
Mixing Time ◽  
Change Rate ◽  
Mixing Method ◽  
Compressive Strength Of Concrete ◽  
Electric Flux ◽  
Strength And Durability ◽  
Forced Mixing ◽  
Peak Value ◽  
Durability Of Concrete

Abstract To study the influence of different mixing times on the performance of concrete under vibration mixing and conventional mixing, C40 and C60 are selected in this paper to verify the influence of mixing time of 60, 75, 90, 105, and 120 s on the compressive strength and durability of concrete comparing vibration mixing and common forced mixing. The results show that the early strength of concrete is more significantly improved in 3 and 7 day; the strength with vibration mixing for mixing 105 s in each age is higher than that of conventional mixing at 120 s; under the condition of guaranteed strength, the mixing time of at least 15 s can be reduced. The strength of C40 concrete with vibration mixing has a peak value with the corresponding mixing time of 105 s, and the rapid growth stage of compressive strength is 15 s earlier than that of conventional mixing. For all mixing time, the electric flux of vibrated concrete is significantly smaller than that of forced concrete, and the change rate is generally above 10%; compared with conventional mixing for 120 s, the durability of C40 and C60 concrete increases by 11.8 and 11.1%, respectively, at the time of vibration mixing for 105 s. It was found that under the same mixing time, the compressive strength of concrete with vibration mixing method is higher than that of conventional mixing. In a certain range, the durability of concrete can be improved by prolonging the mixing time.

Strength Enhancement of Bottom Ash-Based Concretes Using Metakaolin

2011 ◽  
Vol 695 ◽  
pp. 287-290
Author(s):  
J. M. Zhao ◽  
Z. X. Yang ◽  
Kyu Hong Hwang ◽  
M. C. Kim
Keyword(s):  
Compressive Strength ◽  
Fresh Concrete ◽  
Setting Time ◽  
Bottom Ash ◽  
Fine Aggregate ◽  
Test Results ◽  
Replacement Ratio ◽  
Natural Sand ◽  
Strength Enhancement ◽  
Compressive Strength Of Concrete

To replace bottom ash for natural sand completely, the mix proportions of bottom ash in concrete was adjusted according to tab density and replacement ratio of Metakaolin/Cement were established. And then testing for slump, setting time, and compressive strength was conducted. According to test results, the compressive strength of concrete using the bottom ash was lower than that of concrete using natural sand (BAO concrete). But by adjusting the amount of bottom ash in concrete according tab density so that the fine aggregate proportions change 44% to 38%, the compressive strength of concrete using the bottom ash could even be higher than BAO concrete. And the chloric content of concrete using the bottom ash increased as the replacement ratio of bottom ash increased, but it is satisfied with the chloric content of fresh concrete 0.30 kg/m2 below (concrete standard specification regulation value).

Effects of Ultra-Fine Limestone Powder (LP) and Fly Ash Complex Adding on the Workability and Strength of Concrete

2010 ◽  
Vol 152-153 ◽  
pp. 295-300 ◽  
Author(s):  
Lin Wang ◽  
Shao Min Song ◽  
Liu Yang
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Fresh Concrete ◽  
Raw Materials ◽  
Experimental Results ◽  
Limestone Powder ◽  
Environment Protection ◽  
Project Cost ◽  
Air Bubble ◽  
Compressive Strength Of Concrete

Limestone powder is a readily available and inexpensive material. As an admixture, limestone powder partially replacing fly ash or slag which gets serious to supply today has great significance in the aspects of solving raw materials of concrete, reducing project cost and environment protection. Effects of complex adding of ultra-fine limestone powder and fly ash on the workability and strength of concrete are studied in this paper. Experimental results show that: The fluidity of fresh concrete increases with the ratio of ultra-fine LP to fly ash increasing. The slump loss decreases with the ratio of ultra-fine LP to fly ash increasing. When the ratio of LP to fly ash increases from 5:5 to 9:1, the W/B decreases slightly and the slump of concrete almost is in the region of 210-230mm, the compressive strength of concrete remain basically unchanged. The concrete can produce lots of air bubble when the ratio of ultra-fine LP to fly ash exceeds 8:2 .When the proportion of admixtures of ultra LP and fly ash exceeds 50%, the 28 days compressive strength decreases obviously.

Sign in / Sign up

Export Citation Format

Share Document