Development of Nanocement Mortar as a Construction Material

2013 ◽  
Vol 795 ◽  
pp. 684-691 ◽  
Author(s):  
Wail N. Al-Rifaie ◽  
Omar Mohanad Mahdi ◽  
Waleed Khalil Ahmed

The present research examined the compressive and flexural strength of nanocement mortar by using micro cement, micro sand, nanosilica and nanoclay in developing a nanocement mortar which can lead to improvements in ferrocement construction. The measured results demonstrate the increase in compressive and flexural strength of mortars at early stages of hardening. In addition, the influence of heating on compressive strength of cement mortar. General expressions to predict the compressive strength, modulus of rupture for the developed nanocement mortar in the present work are proposed.

2021 ◽  
Vol 13 (8) ◽  
pp. 4546
Author(s):  
Kaiyue Zhao ◽  
Peng Zhang ◽  
Bing Wang ◽  
Yupeng Tian ◽  
Shanbin Xue ◽  
...  

Cement-based materials prepared with activated water induced by a magnetic field or electric field represent a possible solution to environmental issues caused by the worldwide utilization of chemical admixtures. In this contribution, electric- and magnetic-activated water have been produced. The workability and mechanical properties of cement mortar prepared with this activated water have been investigated. The results indicate that the pH and absorbance (Abs) values of the water varied as the electric and magnetic field changed, and their values increased significantly, exhibiting improved activity compared with that of the untreated water. In addition, activated water still retains activity within 30 min of the resting time. The fluidity of the cement paste prepared with electric-activated water was significantly larger than that of the untreated paste. However, the level of improvement differed with the worst performance resulting from cement paste prepared with alternating voltage activated water. In terms of mechanical properties, both compressive strength and flexural strength obtained its maximum values at 280 mT with two processing cycles. The compressive strength increased 26% as the curing time increased from 7 days to 28 days and flexural strength increased by 31%. In addition, through the introduction of magnetic-activated water into cement mortar, the mechanical strength can be maintained without losing its workability when the amount of cement is reduced.


Molecules ◽  
2021 ◽  
Vol 26 (8) ◽  
pp. 2136
Author(s):  
Shaokang Zhang ◽  
Ru Wang ◽  
Linglin Xu ◽  
Andreas Hecker ◽  
Horst-Michael Ludwig ◽  
...  

This paper studies the influence of hydroxyethyl methyl cellulose (HEMC) on the properties of calcium sulfoaluminate (CSA) cement mortar. In order to explore the applicability of different HEMCs in CSA cement mortars, HEMCs with higher and lower molar substitution (MS)/degree of substitution (DS) and polyacrylamide (PAAm) modification were used. At the same time, two kinds of CSA cements with different contents of ye’elimite were selected. Properties of cement mortar in fresh and hardened states were investigated, including the fluidity, consistency and water-retention rate of fresh mortar and the compressive strength, flexural strength, tensile bond strength and dry shrinkage rate of hardened mortar. The porosity and pore size distribution were also analyzed by mercury intrusion porosimetry (MIP). Results show that HEMCs improve the fresh state properties and tensile bond strength of both types of CSA cement mortars. However, the compressive strength of CSA cement mortars is greatly decreased by the addition of HEMCs, and the flexural strength is decreased slightly. The MIP measurement shows that HEMCs increase the amount of micron-level pores and the porosity. The HEMCs with different MS/DS have different effects on the improvement of tensile bond strength in different CSA cement mortars. PAAm modification can improve the tensile bond strength of HEMC-modified CSA cement mortar.


2014 ◽  
Vol 894 ◽  
pp. 55-59
Author(s):  
Abdoullah Namdar ◽  
Fadzil Mat Yahaya ◽  
Kok Jun Jie ◽  
Lim Yen Ping

One of waste agriculture materials is oil palm shell ash. It has been producing in high quantity in palm oil mill, and for storage of that an investment requires. In this paper, an attempt has been made to analysis effect of oil palm shell ash on compressive and flexural strength of cement mortar. The compressive strength and flexural strength of cement mortar has been measured. To improve accuracy of work 50% cement and 50% fine sand has been proposed in cement mortar mix design. The results have been indicated that the effect of OPS ash on flexural and compressive strength of cement mortar is not same. The deflection, load sustainability and time to failure for compressive strength have independent fluctuation of flexural strength. The positive and negative effect of OPS ash on mechanical properties of cement mortar has been observed. The morphology of crack failure has not been investigated. The work can be continued with many waste agriculture materials. Keywords: waste agriculture, deflection, load sustainability, time to failure.


2019 ◽  
Vol 5 (5) ◽  
pp. 1007-1019 ◽  
Author(s):  
Babar Ali ◽  
Liaqat Ali Qureshi ◽  
Ali Raza ◽  
Muhammad Asad Nawaz ◽  
Safi Ur Rehman ◽  
...  

Despite plain cement concrete presenting inferior performance in tension and adverse environmental impacts, it is the most widely used construction material in the world. Consumption of fibers and recycled coarse aggregates (RCA) can add ductility and sustainability to concrete. In this research, two mix series (100%NCA, and 100%RCA) were prepared using four different dosages of GF (0%GF, 0.25%GF, 0.5%GF, and 0.75%GF by volume fraction).  Mechanical properties namely compressive strength, splitting tensile strength, and flexural strength of each concrete mixture was evaluated at the age of 28 days. The results of testing indicated that the addition of GF was very useful in enhancing the split tensile and flexural strength of both RCA and NCA concrete. Compressive strength was not highly sensitive to the addition of GF. The loss in strength that occurred due to the incorporation of RCA was reduced to a large extent upon the inclusion of GF. GF caused significant improvements in the split tensile and flexural strength of RCA concrete. Optimum dosage of GF was determined to be 0.25% for NCA, and 0.5% for RCA concrete respectively, based on the results of combined mechanical performance (MP).


2013 ◽  
Vol 838-841 ◽  
pp. 142-147 ◽  
Author(s):  
Jamilu Usman ◽  
Abdul Rahman Mohd Sam ◽  
Salihuddin Radin Sumadi

An experimental investigation was carried out to assess the effect of metakaolin (MK) on the compressive strength, flexural strength and porosity of cement mortar. The cement was partially substituted with MK at 0-30% replacement levels. The results show that the strengths and porosity of mortar containing up to 20% were superior to that of control (0% MK). The Balshin equation fits the experimental results of compressive strength and porosity of the specimens containing MK and there is a strong quantitative relationship between compressive strength and porosity of the specimens.


2013 ◽  
Vol 652-654 ◽  
pp. 1181-1184
Author(s):  
Guo Qiang Xu ◽  
Zhi Guo You ◽  
Lin Gao ◽  
Dian Li Han

The influence of admixture of super-fine limestone powder and low-quality fly ash in different proportions on the fluidity and strength of cement mortar is studied. The test results show that the mortar fluidity increases with the increase of the super-fine limestone powder (the mixing amount of fly ash reduces), and the strength of cement mortar can improve when limestone powder and low-quality fly ash are combined admixed to a certain ratio. The maximum flexural strength of the 28d mortar is 9.8MPa and its maximum compressive strength is 42.2MPa, and at this time, the limestone powder accounts for 33.3% of the mineral admixtures. However, when the mixing amount of super-fine limestone powder is over a certain range, the strength of 28d cement mortar will reduce.


2010 ◽  
Vol 168-170 ◽  
pp. 456-459
Author(s):  
Hai Yan Yuan ◽  
Shui Zhang ◽  
Guo Zhong Li

By adopting the method of orthogonal experimental design, the effect of three independent variables, that is steel fiber fraction, polypropylene fiber fraction and silica fume fraction on the compressive strength, flexural strength and shrinkage of cement mortar was studied. The results indicate that steel fiber is one of the most important factors affecting compressive strength and shrinkage, and polypropylene fiber is one of the most important factors affecting flexural strength and shrinkage of cement mortar. By using deviation analysis to analyze the orthogonal experiment results, the optimized mix proportion of hybrid fiber reinforced cement mortar is determined. The hybrid effect of steel fiber and polypropylene fiber on the properties of cement mortar is discussed.


2019 ◽  
Vol 2 (1) ◽  
pp. 221-224
Author(s):  
Tek Bahadur Katuwal

Concrete is fundamental construction material widely used for every building structure and other infrastructure. Aggregate has significantfunctions as concrete making materials for the solidity and strength of concrete.The objective of this research was comparative evaluation of crusher and river bed coarse aggregate in respect to the flexural strength of M20 grade concrete with nominal mix. For this research, sample were taken from Kotre Crusher(KC), Kotre River Bed (KR), Hemja Crusher (HC) and Hemja River Bed (HR) considering sand from single source and cement remains singlebrand.Nine cubes (500 mm × 100 mm×100mm) were cast for each sampled source and the flexural strength was determined using a single point load flexural testing machine after 7 days, 14 days and 28 days of curing. The mean flexural strength for the KC, KR, HC and HR sources were 4.86 N/mm2, 4.34 N/mm2, 4.58 N/mm2 and 4.1N/mm2, respectively. Also, the percentageincrement of flexural strength for KC, KR, HC and HR sources are 23.31, 19.11, 19.88 and 18.12 from 7 days to 14 days and 20.90, 16.04, 18.65 and 16.48 from 14 days to 28days respectively. Modulus of rupture of all aggregate sources are greater than theminimum flexural strength as per IS: 456 – 2000. Finally, outcomes of the study indicated that the flexural strength of Kotre Crusher aggregate is more than other sources and all selected samples applicable for construction work.


2021 ◽  
Author(s):  
Gude Reddy Babu ◽  
Pala Gireesh Kumar ◽  
Nelluru Venkata Ramana ◽  
Bhumireddy Madhusudana Reddy

The present examination illustrates the impact on the hardened and fresh cement mortar and cement with the inclusion of nanosilica of size 40 nm in various environmental conditions (UltraTech, India). It is quite notified that an elevation in compressive strength as well as flexural strength along with an improvisation in the performance and life span of cement mortar. The samples of M5 grade blended with a ninety percentage of concrete and remaining with nanosilica was identified to have a finer working elevation in as well as in standards when collated with the conventional cement mortar. The corollary of hardened and fresh cement, strength parameters were looked upon with the aid of XRD (X-ray Diffraction). Also, the SEM (Scanning Electron Microscope) test holds a predominant role in analysis.


Author(s):  
Ali Ahmed ◽  
Shakir Ahmad ◽  
Muhammad Mannal Kaleem ◽  
Muhammad Bilal Zahid

Current study explores the possibility of improvement in various categories of concrete’s strengths (including tensile strength, flexural strength etc.) by using methylcellulose as an additive. The effect of methylcellulose on concrete’s compressive strength has also been investigated experimentally. Concrete samples were casted with several methylcellulose to binder ratios varying from 0.002 to 0.01 by weight of cement. Several tests were performed on concrete specimens including concrete cylinder and cube compression tests, split cylinder tests and modulus of rupture tests. Results showed that addition of methylcellulose increased the tensile strength of concrete. Addition of 0.2% of methylcellulose increased the tensile strength of concrete by 16%. This increase in tensile strength reached up to 73% of the control sample on addition of 1% methylcellulose. It was observed that the effect of methylcellulose on compressive strength of concrete depends upon the type of samples being tested (cube or cylinder). The compressive strength of concrete cylinders showed a plateau behavior with peak at 0.4% methylcellulose content with an increase of 18.7%. Effect of methylcellulose on concrete cylinder strength becomes insignificant beyond 0.6%. It was observed that addition of methylcellulose reduces the modulus of rupture values. The reduction in MOR was only 3% at 0.2% methylcellulose content but it grew to 30% at 1% methylcellulose content. The research presents an effective way of increasing tensile strength of concrete but without significant effect on concrete’s compressive strength and modulus of rupture values. These findings can be used to determine optimum content of methylcellulose to achieve desired performance from concrete depending upon the intended use.


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