Effect of Chain Lengths at Constant Molecular Weights of Water Reducing Admixture on Properties of Cementitious Systems Containing Fly Ash

2021 ◽  
pp. 1-33
Author(s):  
Süleyman Özen ◽  
Muhammet Gökhan Altun ◽  
Ali Mardani-Aghabaglou ◽  
Kambiz Ramyar
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Water Absorption ◽  
Main Chain ◽  
Time Dependent ◽  
Side Chain ◽  
Flow Properties ◽  
Dependent Flow ◽  
Chain Lengths ◽  
Cementitious Systems

In this study, the effect of main chain and side chain length of polycarboxylate-ether based high range water reducing admixture (WRA) on the fresh properties, compressive strength and water absorption of cementitious systems containing 0, 15, 30 and 45 wt.% fly ash was investigated. For this purpose, 3 WRAs with same molecular weight but different chain lengths were produced. According to test results, flowability of paste and mortars was negatively affected when the length of the main chain and side chains of the admixture was longer or shorter than a certain value. This adverse effect is thought to be arisen from the weakening of the adsorption of admixture with increase of its chain lengths. However, when the main chain and side chain lengths of the admixture were shorter or longer than a certain value, the time-dependent flow properties of the mortar mixtures improved. The main chain and side chain lengths of the WRAs had not a significant effect on the compressive strength and water absorption capacity of the mortar mixtures. However, irrespective of the admixture characteristics, with the increase of fly ash substitution the flow and time-dependent flow properties of the mixtures were negatively affected but their water absorption decreased.

scholarly journals Impact of Fly Ash on Time-Dependent Properties of Agro-Waste Lightweight Aggregate Concrete

2021 ◽  
Vol 5 (6) ◽  
pp. 156
Author(s):  
Mehdi Maghfouri ◽  
Vahid Alimohammadi ◽  
Pejman Azarsa ◽  
Iman Asadi ◽  
Yashar Doroudi ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Water Absorption ◽  
Drying Shrinkage ◽  
Lightweight Aggregate ◽  
Time Dependent ◽  
Lightweight Aggregate Concrete ◽  
Aggregate Concrete ◽  
Shrinkage Crack ◽  
Concrete Mixtures

The utilization of by-products and waste materials to substitute for the natural or manufactured resources is considered as a practical way to obtain green building materials. In concrete mixtures, amongst the many available options, Fly Ash (FA) as a by-product pozzolan has been used as a partial replacement of cement. As for the aggregates, lightweight agro-waste oil palm shell (OPS) can be used as a replacement to conventional aggregate for the production of lightweight aggregate concrete. The present communication aims to investigate the impact of FA on time-dependent development properties of OPS lightweight aggregate concrete, including density, water absorption, compressive strength up to 120-days, and drying shrinkage up to the age of 365-days under standard moist curing, partially early curing, and non-curing conditions. Additionally, drying shrinkage crack development was investigated. In this study, two series of concrete mixtures with different substitution levels of OPS (0%, 50%, and 100%) and FA were tested. From the obtained results, it was concluded that the incorporation of fly ash in OPS concrete reduces the density and compressive strength values. Dually, the initial and final water absorption values plus the rate of drying shrinkage at early and long-term ages increased. On top of that, a high potential of drying shrinkage crack, especially for mixtures with 100% OPS, was identified.

scholarly journals BATAKO LUMPUR LAPINDO SEBAGAI ALTERNATIF MATERIAL PASANGAN DINDING

2013 ◽  
Vol 10 (1) ◽  
Author(s):  
Rofikatul Karimah
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Water Absorption ◽  
Building Material ◽  
Class I ◽  
Test Result ◽  
Made In

Block made of mud is a building material used in making wall for building that is made fromsand, cement, and fly ash using certain percentage mud in sand. This research aimed to know theeffect of the use of lapindo mud towards the compressive strength, the absorption of block waterwith the mud dosage in sand are: 0%, 10%, 20%, 30%, and 40%. This research was an experimentalresearch; each design was made in size 10x20x40 cm using 5% of fly ash and without fly ash.The result of this research showed that the highest compressive strength was raised in 10%mud in sand with 5% fly ash that was 195 kg/cm2 or increased about 3.44 kg/cm2 within increasingpercentage about 10.651% towards the compressive of block without lapindo mud with 5% of flyash, and was included in class I quality of block. While for the 30% and 40% mud percentage islower compared with normal compressive strength of block. The test result of water absorption oflapindo mud block showed the higher value than 20% for lapindo mud block with 5% fly ash, inframing the mud blocks as the wall, those blocks need to be soaked first because the absorptionvalue of block is higher than 20%. Lapindo mud block without 5% fly ash has bricks water absorptionless than 20%, while in framing those bricks, they don’t need to be soaked because the absorptionof brick if lower than 20%. By using fly ash in mud block, we can get the higher compressivestrength and the lower water absorption.Keyword: Porong Mud, Block, Fly Ash, Compressive Strength, Absorption

scholarly journals Biofuel Combustion Fly Ash Influence on the Properties of Concrete

2016 ◽  
Vol 7 (5) ◽  
pp. 546-550
Author(s):  
Aurelijus Daugėla ◽  
Džigita Nagrockienė ◽  
Laurynas Zarauskas
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Portland Cement ◽  
Water Absorption ◽  
Frost Resistance ◽  
Ash Content ◽  
Mineral Admixtures ◽  
Binding Agent ◽  
Materials Used ◽  
Plasticizing Admixture

Cement as the binding agent in the production of concrete can be replaced with active mineral admixtures. Biofuel combustion fly ash is one of such admixtures. Materials used for the study: Portland cement CEM I 42.5 R, sand of 0/4 fraction, gravel of 4/16 fraction, biofuel fly ash, superplasticizer, water. Six compositions of concrete were designed by replacing 0%, 5%, 10%, 15% 20%, and 25% of cement with biofuel fly ash. The article analyses the effect of biofuel fly ash content on the properties of concrete. The tests revealed that the increase of biofuel fly ash content up to 20% increases concrete density and compressive strength after 7 and 28 days of curing and decreases water absorption, with corrected water content by using plasticizing admixture. It was found that concrete where 20% of cement is replaced by biofuel ash has higher frost resistance.

Fresh, Durability and Mechanical Behavior of Self Consolidating Concrete Incorporating Fly Ash and Admixture under Hot Weather

2021 ◽  
Vol 904 ◽  
pp. 453-457
Author(s):  
Samer Al Martini ◽  
Reem Sabouni ◽  
Abdel Rahman Magdy El-Sheikh
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Water Absorption ◽  
Weather Conditions ◽  
Chloride Penetration ◽  
The Self ◽  
Fresh Properties ◽  
Self Consolidating Concrete ◽  
Slump Flow ◽  
Hot Weather

The self-consolidating concrete (SCC) become the material of choice by concrete industry due to its superior properties. However, these properties need to be verified under hot weather conditions. The paper investigates the behavior of SCC under hot weather. Six SCC mixtures were prepared under high temperatures. The SCC mixtures incorporated polycarboxylate admixture at different dosages and prolonged mixed for up to 2 hours at 30 °C and 40 °C. The cement paste was replaced with 20% of fly ash (FA). The fresh properties were investigated using slump flow, T50, and VSI tests. The compressive strength was measured at 3, 7, and 28 days. The durability of SCC mixtures was evaluated by conducting rapid chloride penetration and water absorption tests.

scholarly journals Alkali-activated concretes based on fly ash and blast furnace slag: Compressive strength, water absorption and chloride permeability

2020 ◽  
Vol 40 (2) ◽  
Author(s):  
Daniela Eugenia Angulo-Ramírez ◽  
William Gustavo Valencia-Saavedra ◽  
Ruby Mejía de Gutiérrez
Keyword(s):  
Compressive Strength ◽  
Blast Furnace ◽  
Fly Ash ◽  
Water Absorption ◽  
Blast Furnace Slag ◽  
Construction Materials ◽  
Chloride Ion ◽  
Chloride Permeability ◽  
Alkaline Activator ◽  
Furnace Slag

Concretes based on alkaliactivated binders have attracted considerable attention as new alternative construction materials, which can substitute Portland Cement (OPC) in several applications. These binders are obtained through the chemical reaction between an alkaline activator and reactive aluminosilicate materials, also named precursors. Commonly used precursors are fly ash (FA), blast furnace slag (GBFS), and metakaolin. The present study evaluated properties such as compressive strength, rate of water absorption (sorptivity), and chloride permeability in two types of alkaliactivated concretes (AAC): FA/GBFS 80/20 and GBFS/OPC 80/20. OPC and GBFS/OPC* concretes without alkaliactivation were used as reference materials. The highest compressive strength was observed in the FA/GBFS concrete, which reported 26,1% greater strength compared to OPC concrete after 28 days of curing. The compressive strength of alkaliactivated FA/GBFS 80/20 and GBFS/OPC 80/20 was 61 MPa and 42 MPa at 360 days of curing, respectively. These AAC showed low permeability to the chloride ion and a reduced water absorption. It is concluded that these materials have suitable properties for various applications in the construction sector.

The Effect of Curing Time on the Properties of Fly Ash-Based Geopolymer Bricks

2012 ◽  
Vol 626 ◽  
pp. 937-941 ◽  
Author(s):  
W.I. Wan Mastura ◽  
H. Kamarudin ◽  
I. Khairul Nizar ◽  
Mohd Mustafa Al Bakri Abdullah ◽  
H. Mohammed
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Water Absorption ◽  
Sodium Hydroxide ◽  
Sodium Silicate ◽  
Experimental Work ◽  
Base Material ◽  
Curing Time ◽  
Curing Conditions ◽  
Alkaline Activator

This paper reports the results of an experimental work conducted to investigate the effect of curing conditions on the properties of fly ash-based geopolymer bricks prepared by using fly ash as base material and combination of sodium hydroxide and sodium silicate as alkaline activator. The experiments were conducted by varying the curing time in the range of 1-24 hours respectively. The specimens cured for a period of 24 hours have presented the highest compressive strength for all ratio of fly ash to sand. For increasing curing time improve compressive strength and decreasing water absorption.

Experimental Study on Sustainable Concrete with the Mixture of Low Calcium Fly Ash and Lime as a Partial Replacement of Cement

2011 ◽  
Vol 250-253 ◽  
pp. 307-312 ◽  
Author(s):  
Muthuramalingam Jayakumar ◽  
M. Salman Abdullahi
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Water Absorption ◽  
Chloride Ion ◽  
Apparent Volume ◽  
Partial Replacement ◽  
Fly Ash Concrete ◽  
Low Calcium ◽  
Chloride Ion Penetration ◽  
Ion Penetration

Even though the use of fly ash in concrete is nowadays a common practice, its relatively slow pozzolanic reactivity hinders its greater utilization; hence efficient methods of activation are on demand. This study was carried out to evaluate the influence of lime as a chemical activator on the mechanical and durability properties of high strength fly ash concrete. Mixtures were made with 0, 30, 40, and 50% of cement replaced by low calcium fly ash. Corresponding mixtures were also made with the same amount of fly ash and addition of 10% of lime to each mixture. For each concrete mixture, slump, compressive strength, water absorption, sorptivity, apparent volume of permeable voids, and resistance to chloride-ion penetration were measured. The results obtained showed that addition of lime improved the compressive strength significantly at all ages. The strength of all the fly ash mixtures containing lime surpassed that of the corresponding Portland cement mix at 60 days. Addition of lime also improved the sorptivity and resistance to chloride-ion penetration of the fly ash concrete. It however increases the water absorption and the volume of permeable voids of the fly ash concrete.

scholarly journals Properties of Lime Mortar and FAL-G with Urea

2020 ◽  
Vol 8 (5) ◽  
pp. 3458-3460
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Water Absorption ◽  
Viable Alternative ◽  
Lime Mortar ◽  
Urea Fertilizer ◽  
Weight Density

In traditional Indian lime mortar preparation, urine is added to improve the properties. In this research instead of urine, urea (fertilizer)is tried to give a sanitarily viable alternative. Urea is added in the various viz. 1%, 2%, 3%, 4%, 5% with Lime mortar 1:3 and also Fly Ash Lime Gypsum (FAL-G) paste. The resultant composites were cast into cubes of 50 sq.cm area and tested for weight density, water absorption and compressive strength. Results were compared with plain lime mortar cubes and plain FAL-G cubes. FAL-G shows better properties with 3% urea than lime mortar.

scholarly journals Effect of fly ash on physical and mechanical properties of mortar

2019 ◽  
Vol 17 (6) ◽  
pp. 35
Author(s):  
Vu-An Tran
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Fly Ash ◽  
Flexural Strength ◽  
Water Absorption ◽  
Thermal Power ◽  
Setting Time ◽  
Physical And Mechanical Properties ◽  
Flow Density ◽  
Control Specimen

This research investigates the physical and mechanical properties of mortar incorporating fly ash (FA), which is by-product of Duyen Hai thermal power plant. Six mixtures of mortar are produced with FA at level of 0%, 10%, 20%, 30%, 40%, and 50% (by volume) as cement replacement and at water-to-binder (W/B) of 0.5. The flow, density, compressive strength, flexural strength, and water absorption tests are made under relevant standard in this study. The results have shown that the higher FA content increases the flow of mortar but significantly decreases the density of mixtures. The water absorption and setting time increases as the samples incorporating FA. Compressive strength of specimen with 10% FA is approximately equal to control specimen at the 91-day age. The flexural strength of specimen ranges from 7.97 MPa to 8.94 MPa at the 91-day age with the best result for samples containing 10% and 20% FA.

Sign in / Sign up

Export Citation Format

Share Document