The Experts below are selected from a list of 315 Experts worldwide ranked by ideXlab platform
QINGLIN ZHAO - One of the best experts on this subject based on the ideXlab platform.
-
study on lime Fly Ash phosphogypsum binder
Construction and Building Materials, 2007Co-Authors: Weiguo Shen, Mingkai Zhou, QINGLIN ZHAOAbstract:Abstract In this study a new type of lime–Fly Ash–phosphogypsum binder was prepared to improve the performances of lime–Fly Ash binder which was a typical semi-rigid road base material binder in China. The modified lime powder had much higher activity than ordinary quick lime or slaked lime powder, it was the best alkali activator to prepare lime–Fly Ash–phosphogypsum binder. The optimum formulation of this binder was consisted of 8–12% modified lime, 18–23% phosphogypsum and 65–74% Fly Ash. The parallel experiments shown that lime–Fly Ash–phosphogypsum binder had higher strength than ordinary lime, cement, and lime–Fly Ash stabilized soils road base materials, granular soils stabilized with this binder had higher later strength than that of lime–Fly Ash or cement stabilizing granular soil, it had higher early strength and steady strength development. The phosphogypsum hastened the pozzuolana reactions between the lime and Fly Ash, it reacted with lime and Fly Ash also, this reaction formed some AFt and the formation of AFt brought on a slight expansivity which could compensate the shrinkage of the binder. The pore structure of this binder was finer than that of the lime–Fly Ash, so the strength and performances of the road base material stabilized with lime–phosphogypsum–Fly Ash binder was much higher than those of the lime–Fly Ash road base material.
-
Study on lime–Fly Ash–phosphogypsum binder
Construction and Building Materials, 2007Co-Authors: Weiguo Shen, Mingkai Zhou, QINGLIN ZHAOAbstract:Abstract In this study a new type of lime–Fly Ash–phosphogypsum binder was prepared to improve the performances of lime–Fly Ash binder which was a typical semi-rigid road base material binder in China. The modified lime powder had much higher activity than ordinary quick lime or slaked lime powder, it was the best alkali activator to prepare lime–Fly Ash–phosphogypsum binder. The optimum formulation of this binder was consisted of 8–12% modified lime, 18–23% phosphogypsum and 65–74% Fly Ash. The parallel experiments shown that lime–Fly Ash–phosphogypsum binder had higher strength than ordinary lime, cement, and lime–Fly Ash stabilized soils road base materials, granular soils stabilized with this binder had higher later strength than that of lime–Fly Ash or cement stabilizing granular soil, it had higher early strength and steady strength development. The phosphogypsum hastened the pozzuolana reactions between the lime and Fly Ash, it reacted with lime and Fly Ash also, this reaction formed some AFt and the formation of AFt brought on a slight expansivity which could compensate the shrinkage of the binder. The pore structure of this binder was finer than that of the lime–Fly Ash, so the strength and performances of the road base material stabilized with lime–phosphogypsum–Fly Ash binder was much higher than those of the lime–Fly Ash road base material.
Mingkai Zhou - One of the best experts on this subject based on the ideXlab platform.
-
Effect of Fly Ash Content on Mechanical Properties of Cement-Fly Ash Stabilized Crushed Stones
Applied Mechanics and Materials, 2014Co-Authors: Xiao Chen, Mingkai ZhouAbstract:To improve the impact of Fly Ash on the properties of cement-Fly Ash stabilized crushed stone, and promote it popularize and apply better. This paper investigated the effect of Fly Ash content on unconfined compressive strength, cleavage strength and resilient modulus of cement-Fly Ash stabilized crushed stones, and those relationships between mechanical parameters. The results showed that with increasing of the Fly Ash content, the unconfined compressive strength and cleavage strength increased at first, then decreased, the resilient modulus decreased, and The brittleness index increased. We can conclude that the optimal Fly Ash content is between 10% and 15%, and increment of Fly Ash content can improve its crack-resistance.
-
Effect of Fly Ash Content on Mechanical Properties of Cement-Fly Ash Stabilized Crushed Stones
Advanced Materials Research, 2010Co-Authors: Xiao Chen, Mingkai ZhouAbstract:This paper investigates the effect of Fly Ash content on unconfined compressive strength, cleavage strength and resilient modulus of cement-Fly Ash stabilized crushed stones. The relationships between mechanical parameters were also studied. The results show that with Fly Ash content increasing, the unconfined compressive strength and cleavage strength were increasing firstly but decreased then, and the resilient modulus were decreasing. The brittleness index was increased by the increment of Fly Ash content. It can be concluded that the optimal Fly Ash content in cement-Fly Ash stabilized crushed stones is between 10% and 15%, and increment of Fly Ash content can improve its crack-resistance.
-
study on lime Fly Ash phosphogypsum binder
Construction and Building Materials, 2007Co-Authors: Weiguo Shen, Mingkai Zhou, QINGLIN ZHAOAbstract:Abstract In this study a new type of lime–Fly Ash–phosphogypsum binder was prepared to improve the performances of lime–Fly Ash binder which was a typical semi-rigid road base material binder in China. The modified lime powder had much higher activity than ordinary quick lime or slaked lime powder, it was the best alkali activator to prepare lime–Fly Ash–phosphogypsum binder. The optimum formulation of this binder was consisted of 8–12% modified lime, 18–23% phosphogypsum and 65–74% Fly Ash. The parallel experiments shown that lime–Fly Ash–phosphogypsum binder had higher strength than ordinary lime, cement, and lime–Fly Ash stabilized soils road base materials, granular soils stabilized with this binder had higher later strength than that of lime–Fly Ash or cement stabilizing granular soil, it had higher early strength and steady strength development. The phosphogypsum hastened the pozzuolana reactions between the lime and Fly Ash, it reacted with lime and Fly Ash also, this reaction formed some AFt and the formation of AFt brought on a slight expansivity which could compensate the shrinkage of the binder. The pore structure of this binder was finer than that of the lime–Fly Ash, so the strength and performances of the road base material stabilized with lime–phosphogypsum–Fly Ash binder was much higher than those of the lime–Fly Ash road base material.
-
Study on lime–Fly Ash–phosphogypsum binder
Construction and Building Materials, 2007Co-Authors: Weiguo Shen, Mingkai Zhou, QINGLIN ZHAOAbstract:Abstract In this study a new type of lime–Fly Ash–phosphogypsum binder was prepared to improve the performances of lime–Fly Ash binder which was a typical semi-rigid road base material binder in China. The modified lime powder had much higher activity than ordinary quick lime or slaked lime powder, it was the best alkali activator to prepare lime–Fly Ash–phosphogypsum binder. The optimum formulation of this binder was consisted of 8–12% modified lime, 18–23% phosphogypsum and 65–74% Fly Ash. The parallel experiments shown that lime–Fly Ash–phosphogypsum binder had higher strength than ordinary lime, cement, and lime–Fly Ash stabilized soils road base materials, granular soils stabilized with this binder had higher later strength than that of lime–Fly Ash or cement stabilizing granular soil, it had higher early strength and steady strength development. The phosphogypsum hastened the pozzuolana reactions between the lime and Fly Ash, it reacted with lime and Fly Ash also, this reaction formed some AFt and the formation of AFt brought on a slight expansivity which could compensate the shrinkage of the binder. The pore structure of this binder was finer than that of the lime–Fly Ash, so the strength and performances of the road base material stabilized with lime–phosphogypsum–Fly Ash binder was much higher than those of the lime–Fly Ash road base material.
Weiguo Shen - One of the best experts on this subject based on the ideXlab platform.
-
study on lime Fly Ash phosphogypsum binder
Construction and Building Materials, 2007Co-Authors: Weiguo Shen, Mingkai Zhou, QINGLIN ZHAOAbstract:Abstract In this study a new type of lime–Fly Ash–phosphogypsum binder was prepared to improve the performances of lime–Fly Ash binder which was a typical semi-rigid road base material binder in China. The modified lime powder had much higher activity than ordinary quick lime or slaked lime powder, it was the best alkali activator to prepare lime–Fly Ash–phosphogypsum binder. The optimum formulation of this binder was consisted of 8–12% modified lime, 18–23% phosphogypsum and 65–74% Fly Ash. The parallel experiments shown that lime–Fly Ash–phosphogypsum binder had higher strength than ordinary lime, cement, and lime–Fly Ash stabilized soils road base materials, granular soils stabilized with this binder had higher later strength than that of lime–Fly Ash or cement stabilizing granular soil, it had higher early strength and steady strength development. The phosphogypsum hastened the pozzuolana reactions between the lime and Fly Ash, it reacted with lime and Fly Ash also, this reaction formed some AFt and the formation of AFt brought on a slight expansivity which could compensate the shrinkage of the binder. The pore structure of this binder was finer than that of the lime–Fly Ash, so the strength and performances of the road base material stabilized with lime–phosphogypsum–Fly Ash binder was much higher than those of the lime–Fly Ash road base material.
-
Study on lime–Fly Ash–phosphogypsum binder
Construction and Building Materials, 2007Co-Authors: Weiguo Shen, Mingkai Zhou, QINGLIN ZHAOAbstract:Abstract In this study a new type of lime–Fly Ash–phosphogypsum binder was prepared to improve the performances of lime–Fly Ash binder which was a typical semi-rigid road base material binder in China. The modified lime powder had much higher activity than ordinary quick lime or slaked lime powder, it was the best alkali activator to prepare lime–Fly Ash–phosphogypsum binder. The optimum formulation of this binder was consisted of 8–12% modified lime, 18–23% phosphogypsum and 65–74% Fly Ash. The parallel experiments shown that lime–Fly Ash–phosphogypsum binder had higher strength than ordinary lime, cement, and lime–Fly Ash stabilized soils road base materials, granular soils stabilized with this binder had higher later strength than that of lime–Fly Ash or cement stabilizing granular soil, it had higher early strength and steady strength development. The phosphogypsum hastened the pozzuolana reactions between the lime and Fly Ash, it reacted with lime and Fly Ash also, this reaction formed some AFt and the formation of AFt brought on a slight expansivity which could compensate the shrinkage of the binder. The pore structure of this binder was finer than that of the lime–Fly Ash, so the strength and performances of the road base material stabilized with lime–phosphogypsum–Fly Ash binder was much higher than those of the lime–Fly Ash road base material.
Ran Huang - One of the best experts on this subject based on the ideXlab platform.
-
Utilization of Circulating Fluidized Bed Combustion (CFBC) Fly Ash and Coal-Fired Fly Ash in Portland Cement
Key Engineering Materials, 2014Co-Authors: Ran Huang, Tehsien WuAbstract:Circulating fluidized bed combustion (CFBC) Fly Ash is a promising admixture for construction and building materials due to its pozzolanic activity and self-cementitious property. In this study, CFBC Fly Ash and coal-fired Fly Ash were used in Portland cement to investigate the pozzolanic and cementitious characteristics of CFBC Fly Ash and the properties of cement-based composites. Tests show that CFBC Fly Ash has the potential instead of cementing materials and as an alternative of pozzolan. In fresh specimens, the initial setting time of mortars increases with the increasing amount of cement replacement by CFBC Fly Ash and coal-fire Fly Ash. In harden specimens, adding CFBC Fly Ash to replace OPC reduces the compressive strength. Meanwhile, CFBC Fly Ash would results in a higher length change when adding over 30%. Based on the results, the amount of CFBC Fly Ash replacement cement was recommended to be limited below 20%.
-
Characteristics of CFBC Fly Ash and properties of cement-based composites with CFBC Fly Ash and coal-fired Fly Ash
Construction and Building Materials, 2014Co-Authors: Tehsien Wu, Ran HuangAbstract:The aim of this study is to investigate the pozzolanic and cementitious characteristics of circulating fluidized bed combustion (CFBC) Fly Ash and the properties of cement-based composites with various combinations of CFBC Fly Ash and coal-fired Fly Ash. Setting time test, compressive strength test and length change test were performed to measure fresh and hardened properties. Test results showed that the CFBC Fly Ash cannot meet the chemical and physical requirements in ASTM C821-09 (Standard specification for lime for use with pozzolans), but is consistent with the requirements of ASTM C593-11 (Specification for Fly Ash and other pozzolans for use with lime for soil stabilization). It indicates that CFBC Fly Ash has the potential instead of cementing materials and as an alternative of pozzolan. The initial setting time increases with an increasing amount of cement replacement by CFBC Fly Ash and coal-fire Fly Ash. The lower compressive strength has been obtained in mortar with various combinations of coal-fired Fly Ash and CFBC Fly Ash than the comparable ordinary Portland cement (OPC) mortar. Coal-fired Fly Ash can be effectively used in reducing the length change. However, CFBC Fly Ash would results in a higher length change when adding over 30%. Thus, the amount of CFBC Fly Ash replacement cement was recommended to be limited below 20%.
-
Durability Performance of Concrete Containing CFBC Fly Ash and Coal-Fired Fly Ash
Applied Mechanics and Materials, 2014Co-Authors: Ran HuangAbstract:This study presents an investigation into durability performance of concrete with various combinations of circulating fluidized bed combustion (CFBC) Fly Ash and coal-fired Fly Ash. All cylindrical specimens with the same binder content of 420 kg/m3 and water/binder ratio of 0.5 were cast and cured in the saturated limewater. Permeability test, sulfate attack resistance test, rapid chloride ion penetration test (RCPT) and carbonization test were performed. Test results demonstrate that the adding of CFBC Fly Ash and coal-fired Fly Ash would reduce the water permeability and chloride ions penetration, and increase the sulfate attack resistance, but an increase in carbonization depth. The carbonization depth increases with an increasing contents of CFBC Fly Ash and coal-fired Fly Ash. There exists a negative relationship between compressive strength and carbonization rate. Based on the test results, CFBC Fly Ash and coal-fired Fly Ash can be considered as cement replacement materials and employed in concrete.
Djwantoro Hardjito - One of the best experts on this subject based on the ideXlab platform.
-
CONSISTENCY OF Fly Ash QUALITY FOR MAKING HIGH VOLUME Fly Ash CONCRETE
Jurnal Teknologi, 2017Co-Authors: Antoni Antoni, Alvin Krisnanta Widianto, Jerry Lakshmana Wiranegara, Djwantoro HardjitoAbstract:Fly Ash is a by-product of coal burning and is widely used as a substitute for cement material. The advantages of using Fly Ash in concrete include the improvement of workability and reduction of bleeding and segregation. The problem often encountered when using Fly Ash is the uncertainty of the Fly Ash quality. The quality is influenced by the coal origin, burning technique, mineral content, and capturing method. In this study, the consistency of Fly Ash from one power plant source was investigated for making a high-volume Fly Ash (HVFA) mortar. Variations in Fly Ash can be detected by applying rapid indicators as suggested in this paper; i.e., the pH of the Fly Ash in aqueous solution, the percentage of Fly Ash particles passing sieve #325 and the superplasticizer demand for the targeted slump flow. The Fly Ash replacement ratio was varied from 10–60% of cement, by mass. The results showed a large variation in the chemical content of the Fly Ash as shown by variation in pH, whereas only slight variation in the physical properties of the Fly Ash, i.e. particle size and shape. Superplasticizer demand for the same flow diameter was reduced with the increase of Fly Ash content, whereas the optimum Fly Ash replacement ratio for maximum strength varied among Fly Ash from different sampling periods. The compressive strength could reach that of control specimens at a replacement ratio of 20–30%, and mortar compressive strength of 42 MPa was still achievable at a replacement ratio of 50%.
-
A review on the effect of Fly Ash characteristics and their variations on the synthesis of Fly Ash based geopolymer
2017Co-Authors: Oswyn Karsten Wattimena, Antoni, Djwantoro HardjitoAbstract:There are more than four decades since the last 1970s where geopolymers concrete was first introduced and developed to use as a replacement to conventional concrete material which uses cement as a binder. And since the last two decades, geopolymers which utilized Fly Ash as aluminosilicate source material, i.e. Fly Ash based geopolymers, have been investigated. Many researchers present how to produce the best Fly Ash based geopolymer with a various source of constituent material as well as mixing formula to achieve exceptional concrete performance. Although there is a similar trend towards factors affecting the result of Fly Ash based geopolymer synthesis, there is still remain a wide range in mixture proportion. The considerable variation in Fly Ash characteristics as source material in the synthesis can very likely be one of the causes of this problem. This paper attempts to identify the effect of source material variation of geopolymer concrete, particularly which use Fly Ash as source material and focuses on the variation of its characteristics and the effects to properties of concrete. From the reviews it concluded that different sources (and even the same source, but different batch) of Fly Ash materials will give some different characteristics of the Fly Ash, where it would affect the synthesis process of the Fly Ash based geopolymer concretes.There are more than four decades since the last 1970s where geopolymers concrete was first introduced and developed to use as a replacement to conventional concrete material which uses cement as a binder. And since the last two decades, geopolymers which utilized Fly Ash as aluminosilicate source material, i.e. Fly Ash based geopolymers, have been investigated. Many researchers present how to produce the best Fly Ash based geopolymer with a various source of constituent material as well as mixing formula to achieve exceptional concrete performance. Although there is a similar trend towards factors affecting the result of Fly Ash based geopolymer synthesis, there is still remain a wide range in mixture proportion. The considerable variation in Fly Ash characteristics as source material in the synthesis can very likely be one of the causes of this problem. This paper attempts to identify the effect of source material variation of geopolymer concrete, particularly which use Fly Ash as source material and foc...
-
MECHANICAL ACTIVATION OF Fly Ash FOR MAKING HIGHVOLUME Fly Ash CONCRETE
2014Co-Authors: Antoni, Vindy Satrya, Djwantoro HardjitoAbstract:Fly Ash - waste product from industrial process - seldom receives proper attention during the production stage, and thus its chemical composition and other properties are varied. Quality of Fly Ash is determined by the efficiency of combustion and the type of coal used. It can be detected also from the value of Lost on Ignition (LOI). This paper evaluates changes on Fly Ash after undergone grinding using rod mill, and determines its suitability to be used in making high volume Fly Ash (HVFA) concrete. Samples of Fly Ashes were taken from four different sources, i.e. two samples from a power plant, and one each from textile factory and paper mill. Samples taken from power plant have low Loss on Ignition (LOI), while the other have very high LOIs. Fly Ash samples were ground using a rod mill to evaluate the changes in the properties of Fly Ash and HVFA mortar. The workability of HVFA mortar was controlled by adjusting the superplasticizer content to obtain the target slump with constant water to cementitious ratio. The results shows that the specific gravity of Fly Ash increases after grinding. Utilizing ground Fly Ash ends up with more significant strength increase of HVFA mortar, especially with those of high LOI values. The strength increase of HVFA mortar utilizing ground Fly Ash shows that milling of the Fly Ash is an excellent method for beneficiation of Fly Ash, especially to the one with high LOI value and low specific gravity.
