Influence of Triethanolamine on the Properties of Cement-Based Materials

2017 ◽  
Vol 898 ◽  
pp. 2010-2017 ◽  
Author(s):  
Xiao Ying Wang ◽  
Ming Zhang Lan ◽  
Wei Fang Hou ◽  
Bin Feng Xiang ◽  
Xu Dong Zhao
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Cement Hydration ◽  
Setting Time ◽  
Cementitious Materials ◽  
Hydration Products ◽  
Initial Setting Time ◽  
Final Setting Time ◽  
Retarding Effect ◽  
Initial Setting

The effects of triethanolamine on the compressive strength and setting time of fly ash cementitious materials, slag cementitious materials, and limestone cementitious materials were investigated. The results show that the dosage of 0.04% of triethanolamine can significantly improve the 3d, 7d and 28d compressive strength of fly ash cementitious materials. It possesses less impact on the setting time. The dosage of 0.04% of triethanolamine can significantly improve the 3d and 7d compressive strength of slag cementitious materials while the effect of late strength is not obvious. It extends the initial setting time and the final setting time is not changed, which has retarding effect. The results of hydration heat and XRD show that triethanolamine extends the induction period of cement hydration, and gypsum is exhausted in advance during the hydration process. Triethanolamine promotes the transformation of AFt to AFm and there is no effect on the type of hydration products.

Effect of Citric Acid on Cement Hydration

2011 ◽  
Vol 393-395 ◽  
pp. 49-53 ◽  
Author(s):  
Bao Guo Ma ◽  
Jun Xiao ◽  
Hong Bo Tan
Keyword(s):  
Citric Acid ◽  
Cement Hydration ◽  
Setting Time ◽  
Initial Setting Time ◽  
Final Setting Time ◽  
Retarding Effect ◽  
Initial Setting ◽  
Flow Loss ◽  
Diffraction Peaks ◽  
Acid Dosage

Through the test of citric acid of cement paste, setting time and compression strength changes, and combined with XRD, SEM, discusses the influence of citric acid on cement hydration process. The results show that: citric acid can effectively increase the initial cement fluidity, when the content is exceed to 0.1%, the 60 min flow loss of increased gradually. Citric acid retarding effect increases with dosage, but there is a critical dosage, when the dosage is less than 0.1%, the initial setting time and final setting time increased slowly; When the dosage more than 0.1%, the initial setting time increased slowly, but the final setting time increases rapidly; With the increase in citric acid dosage, AFt diffraction peaks increases, while the CH peak decreases, indicating that the citric acid accelerated the initial hydration of C3A, while inhibiting C3S hydration and promoting AFt generation

scholarly journals Compressive Strength and Setting Time of MTA and Portland Cement Associated with Different Radiopacifying Agents

2012 ◽  
Vol 2012 ◽  
pp. 1-4 ◽  
Author(s):  
Mario Tanomaru-Filho ◽  
Vanessa Morales ◽  
Guilherme F. da Silva ◽  
Roberta Bosso ◽  
José M. S. N. Reis ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Portland Cement ◽  
Zirconium Oxide ◽  
Setting Time ◽  
Strontium Carbonate ◽  
Strength Test ◽  
Initial Setting Time ◽  
Final Setting Time ◽  
Compressive Strength Test ◽  
Initial Setting

Objective. The aim of this study was to evaluate the compressive strength and setting time of MTA and Portland cement (PC) associated with bismuth oxide (BO), zirconium oxide (ZO), calcium tungstate (CT), and strontium carbonate (SC). Methods. For the compressive strength test, specimens were evaluated in an EMIC DL 2000 apparatus at 0.5 mm/min speed. For evaluation of setting time, each material was analyzed using Gilmore-type needles. The statistical analysis was performed with ANOVA and the Tukey tests, at 5% significance. Results. After 24 hours, the highest values were found for PC and PC + ZO. At 21 days, PC + BO showed the lowest compressive strength among all the groups. The initial setting time was greater for PC. The final setting time was greater for PC and PC + CT, and MTA had the lowest among the evaluated materials (P<0.05). Conclusion. The results showed that all radiopacifying agents tested may potentially be used in association with PC to replace BO.

scholarly journals Effect of Naphthalene-Based Superplasticizer and Polycarboxylic Acid Superplasticizer on the Properties of Sulfoaluminate Cement

Materials ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 662
Author(s):  
Yonghua Wu ◽  
Qiqi Li ◽  
Guoxin Li ◽  
Shiying Tang ◽  
Mengdie Niu ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Setting Time ◽  
Hydration Products ◽  
Polycarboxylic Acid ◽  
X Ray Diffraction ◽  
Calcium Sulfoaluminate Cement ◽  
X Ray ◽  
Initial Setting Time ◽  
Calcium Sulfoaluminate ◽  
Initial Setting

In order to study what the effect of superplasticizers on the setting time, fluidity and compressive strength of calcium sulfoaluminate cement (CSA) a naphthalene-based superplasticizer (BNS) and a polycarboxylic acid superplasticizer (PC) were selected to interact with CSA pastes and ye’elimite, respectively. X-ray diffraction (XRD), thermogravimetric (TG) analysis and scanning electron microscopy (SEM) analytical methods were used to investigate the class, amount and microstructure of the CSA pastes and ye’elimite pastes hydration products under the effect of the superplasticizers. The results showed that the addition of BNS can promote ettringite generation and thus improve the early compressive strength. As the addition of BNS increased from 0.8 wt% to 2.0 wt%, the initial setting time was prolonged 10 min, the final setting time was prolonged 7 min, the 5 min fluidity was improved from no fluidity to 220 mm. However, as the addition of PC increased from 0.08 wt% to 0.20 wt%, the setting time of the PC just changed within 3 min; the 5 min fluidity increased from 110 mm to 195 mm and no 15 min fluidity at all was observed. AS seen by SEM, it can be stated that generated ettringite under the addition of PC was layered and lacking bonding, and its morphology changed from rod-like to flake-like, leading to a decrease in early compressive strength.

scholarly journals Influence of Ultrafine Natural Steatite Powder on Setting Time and Strength Development of Cement

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
K. Sudalaimani ◽  
M. Shanmugasundaram
Keyword(s):  
Compressive Strength ◽  
Setting Time ◽  
Element Distribution ◽  
Strength Development ◽  
X Ray Diffraction ◽  
Dormant Period ◽  
Initial Setting Time ◽  
Final Setting Time ◽  
Initial Setting ◽  
Cement Binder

This paper deals with the setting time and pozzolanic activity of cement when ultra fine natural steatite powder (UFNSP) is used as replacement for cement. Initial setting time, final setting time, and mortar cube strength were studied, due to the replacement of ultra fine natural steatite powder with cement at 5%, 10%, 15%, 20%, and 25% by mass of cement. The setting time of fresh cement-binder paste and compressive strength of mortar cubes are observed. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) were applied to investigate the microstructural behaviour and chemical element distribution inside cement-binder matrix. Results indicate that the length of dormant period is shortened. The replacement of ultra fine natural steatite powder with cement reduces initial setting time, and final setting time and increases mortar cube compressive strength.

scholarly journals Investigation on the Compressive Strength and Time of Setting of Low-Calcium Fly Ash Geopolymer Paste Using Response Surface Methodology

Polymers ◽  
2021 ◽  
Vol 13 (20) ◽  
pp. 3461
Author(s):  
Pauline Rose J. Quiatchon ◽  
Ithan Jessemar Rebato Dollente ◽  
Anabel Balderama Abulencia ◽  
Roneh Glenn De Guzman Libre ◽  
Ma. Beatrice Diño Villoria ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Unconfined Compressive Strength ◽  
Setting Time ◽  
Initial Setting Time ◽  
Alkali Activator ◽  
Setting Times ◽  
Confirmatory Tests ◽  
Initial Setting

Approximately 2.78 Mt of coal fly ash is produced in the Philippines, with a low utilization rate. Using fly ash-based geopolymer for construction will lessen the load sent to landfills and will result in lower GHG emissions compared to OPC. It is necessary to characterize the fly ash and optimize the geopolymer components to determine if it can replace OPC for in situ applications. The activator-to-precursor ratio, the water-to-solids ratio, and the sodium hydroxide-to-sodium silicate ratio were optimized using a randomized I-optimal design from the experimental results of 21 runs with five replicates, for a total of 105 specimens of 50 mm × 50 mm × 50 mm paste cubes. The engineering properties chosen as the optimization responses were the unconfined compressive strength (UCS), the initial setting time, and the final setting time. The samples were also ambient-cured with the outdoor temperature ranging from 30 °C to 35 °C and relative humidity of 50% ± 10% to simulate the on-site environment. Runs with high unconfined compressive strength (UCS) and short setting times were observed to have a low water-to-solids (W/S) ratio. All runs with a UCS greater than 20 MPa had a W/S ratio of 0.2, and the runs with the lowest UCS had a W/S of 0.4. The initial setting time for design mixes with a W/S ratio of 0.2 ranged from 8 to 105 min. Meanwhile, five out of seven design mixes with a W/S ratio of 0.4 took longer than 1440 min to set. Specimens with an alkali activator ratio (NaOH/WG) of 0.5 (1:2) and 0.4 (1:2.5) also had significantly lower setting times than those with an alkali activator ratio of 1. The RSM model was verified through confirmatory tests. The results of the confirmatory tests are agreeable, with deviations from the expected UCS ranging from 0 to 38.12%. The generated model is a reliable reference to estimate the UCS and setting time of low-calcium FA geopolymer paste for in situ applications.

scholarly journals Investigation of Portland cement composites containing high amounts of different kinds of fly ashes

2019 ◽  
Author(s):  
Iwona Wilińska ◽  
Barbara Pacewska ◽  
Wojciech Kubissa
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Setting Time ◽  
Cement Composite ◽  
Fly Ashes ◽  
Cement Pastes ◽  
Initial Setting Time ◽  
Initial Setting ◽  
Lower Heat ◽  
The Impact

Utilization of fluidized fly ash in cement composite is problematic, e.g. because of its changeable chemical composition and increased water demand of the mixture. However, this kind of by-product shows some self-cementing properties, which may be beneficial for low-cement mixtures. The article compares the impact of various kinds of fly ashes, i.e. fluidized fly ash and conventional one, and their mixtures on hydration of fly ash–cement compositions in relation to properties of final material. The amount of fly ash in the binder was 50 wt%. Calorimetry, thermal analysis (TG/DTG) and infrared spectroscopy were used. Compressive strength and water absorption of hardened composites were also registered. It was found that both fly ashes exhibit delay effect in fly ash-cement pastes which causes extension of initial setting time and lower heat released compared to the reference without fly ash. At later hydration days, fluidized fly ash develops higher pozzolanic activity than conventional one. Compositions with fluidized fly ash show better compressive strength compared to those containing conventional one. Mixing of different materials of high and low activity (fluidized and conventional fly ash in this case) seems to be a good way for creation of new cement replacement material.

The Influence of Alcohol Amine Admixtures on the Macroscopic Properties of Portland Cement Paste

2014 ◽  
Vol 525 ◽  
pp. 573-579
Author(s):  
Tian Yong Huang ◽  
Dong Min Wang ◽  
Ze Liu
Keyword(s):  
Compressive Strength ◽  
Flexural Strength ◽  
Portland Cement ◽  
Cement Paste ◽  
Setting Time ◽  
Initial Setting Time ◽  
Final Setting Time ◽  
Cement Mortars ◽  
Macroscopic Properties ◽  
Initial Setting

It is studied the influence of triethanolamine (TEA), diethylenetriamine (DEA), Triisopropanolamine (TIPA), aminoethyl ethanolamine (AE), and polyvinyl alcohol ammonium phosphate (PAAP) at different dosages on the properties of fresh and hardened cement pastes and mortars prepared by Portland cement, including standard consistency water, setting time, the cement paste fluidity, and compressive and flexural strength. It is showed that the high polarity alcohol amine molecules exhibit strong chemical interactions with cement matrix, which are reflected in modified macroscopic properties of the cement system. All alcohol amine admixtures increased the standard consistency water and decreased cement paste fluidity of Portland cement. TEA significantly shortened the initial setting time and final setting time of Portland cement. On the other hand, TIPA, DEA, AE and PAAP extended the initial setting time of cement but shortened the cement final setting time. All alcohol amine admixtures except TIPA at 0.2 and 0.5 dosage increased the compressive and flexural strength of the Portland cement mortars at 3 days. Especially when the dosage of PAAP is 1, the compressive strength of the Portland cement mortars at 3 days is increased 10.5MPa. All alcohol amine admixtures except AE at 0.2 and 0.5 dosage increase the compressive and flexural strength of the Portland cement mortars at 28 days, Especially when the dosage of TIPA is 1, the compressive strength of the Portland cement mortars at 28 days is increased 8.8MPa.

Compressive Strength and Setting Time Modification of Class C Fly Ash-Based Geopolymer Partially Replaced with Kaolin and Metakaolin

2018 ◽  
Vol 766 ◽  
pp. 157-163 ◽  
Author(s):  
Khanthima Hemra ◽  
Shuntaro Yamaguchi ◽  
Takaomi Kobayashi ◽  
Pavadee Aungkavattana ◽  
Sirithan Jiemsirilers
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Calcium Oxide ◽  
Setting Time ◽  
Xrd Analysis ◽  
Raw Material ◽  
Initial Setting Time ◽  
High Calcium ◽  
Initial Setting ◽  
Class C

Class C fly ash is widely used as a geopolymer raw material. It contains high calcium oxide and iron oxide resulting in a fast setting property. The influence of using kaolin and metakaolin replaced class C fly ash in geopolymer processing were investigated in term of compressive strength and setting time. Kaolin and metakaolin which calcined at different temperature of 600°C and 700°C replaced Class C fly ash between 0 to 50 wt. %. The geopolymers were prepared at constant KOH concentration as 6.0 M, K2SiO3/KOH ratio as 1.0, solid/liquid ratio as 1.5 and 7 days of curing. The compressive strength is obviously increased when fly ash was replaced with both kinds of metakaolin, although, it is inclined to decrease when replaced by kaolin. The compressive strength is increased up to 13% and 47% with the replacement by 50 wt. % of metakaolin calcined at 600°C and 700°C, respectively. On the other hand, the replacement by 50 wt. % of kaolin give the initial setting time prolonging from about 6 min to 80 min. However, the initial setting time of metakaolin calcined at 600°C and 700°C replacement is also improved to about 37 min and 20 min, respectively. These results from their difference of amorphous phase and reactivity of the replacement materials. XRD analysis reveals the combination phases of amorphous geopolymer gel that is the broad hump centered at 28 – 30° 2θ, and products from the reaction such as calcium oxide, arcanite, calcium silicate hydrate, quartz and muscovite which the two latter are from unreacted metakaolin. They are confirmed by FT-IT result and microstructure evaluation by SEM. Therefore, the partially replacement of fly ash with kaolin and metakaolin in fly ash-based geopolymer production are affected to the compressive strength and resulted to modify the setting time.

Study on the Properties of Ground Limestone-High Alumina Cement Gelation System

2011 ◽  
Vol 317-319 ◽  
pp. 489-497
Author(s):  
Jia Xiao ◽  
Cheng Fu Gou ◽  
Cai Yun Xu ◽  
Hao Xing ◽  
Yong Gang Jin
Keyword(s):  
Compressive Strength ◽  
Setting Time ◽  
High Alumina ◽  
Alumina Cement ◽  
Initial Setting Time ◽  
Final Setting Time ◽  
High Alumina Cement ◽  
Binder Ratio ◽  
Initial Setting ◽  
Ground Limestone

Effects of various amounts of ground limestone on the setting time, fluidity and compressive strength of high alumina cement were described in this paper. Microstructure analyses were performed by SEM. The results indicate that the initial setting time, the final setting time, the fluidity and the compressive strength of the pastes increase first and decrease later with the ground limestone content increasing, all of which reach the maximum when the ground limestone content is 3%. Meanwhile, an increase of the fineness of the ground limestone produces a shorter setting time, the fluidity of the pastes increases when the content of the ground limestone increases, and the compressive strength of the hardened pastes increases with the ground limestone content increasing and decreases with water-binder ratio increasing. The 28d strength of the pure high alumina cement paste is lower than the 3d strength, appearing the strength shrinkage, which can be improved by a proper addition of the ground limestone.

scholarly journals Experimental Study on Mechanical Properties of Repair Materials for Underwater Rapid Construction

2022 ◽  
Vol 2148 (1) ◽  
pp. 012062
Author(s):  
Shangchuan Zhao ◽  
Longlong Liu ◽  
Xindai Zuo ◽  
Shaopeng Wang
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Setting Time ◽  
Cement Concrete ◽  
Initial Setting Time ◽  
Sulphoaluminate Cement ◽  
Final Setting Time ◽  
Rapid Construction ◽  
Repair Materials ◽  
Initial Setting

Abstract Several strength grades of sulphoaluminate cement concrete were designed, and the mechanical properties with different mix ratios were studied. This paper mainly analyzes the mechanical properties of sulphoaluminate cement concrete with the setting time test, compressive strength test and flexural test. The test results show that the setting time of cement concrete can be controlled by mixing different admixtures. One hand, the initial setting time increases from 34 min to 340 min, and the final setting time increases from 57 min to 580 min when the incorporated borax content changes from 0 to 1.0 %. Other hand, the initial setting time decreased from 34 min to 11 min, and the final setting time increased from 57 min to 18 min, when the incorporated borax content changed from 0 to 0.5 %. Furthermore, the compressive strength can reach 40 MPa, and the flexural strength can reach more than 2.5MPa after 6 hours of curing. The experiment results illustrate that the setting time and the mechanical properties satisfy the needs of the rapid construction requirements under normal temperature conditions.

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