Mechanical Properties of Reproduced Historic Mosaic Mortar

2021 ◽  
Vol 325 ◽  
pp. 86-91
Author(s):  
Pavla Bauerová ◽  
Pavel Reiterman ◽  
Magdalena Kracík Štorkánová ◽  
Martin Keppert

Mortars containing linseed oil as admixture to lime were identified in several mosaics found in Czech Republic. These mosaics were made around 1900 and the composition of their bedding mortar was likely influenced by publication La Mosaïque by E. Gerspach [1], published in Paris, 1880. The recipe for lime mortar with linseed oil and stand oil has been reproduced within the present paper. Four mixes were prepared with varying oil/stand oil content (below, above and according to Gerspach’s recommendation). The primary motivation of mosaic artists to use oil admixture was to keep the mortar’s plasticity for longer time, what is beneficial for the mosaic tesseraes (stones) adjustment. This effect was quantified by help of Vicat apparatus. The influence of oils on mechanical properties and carbonation was evaluated at 28 days. It was found by XRD, that the rate of carbonation is reduced due to the oil presence. It is caused by fact that the oil acts also as water-repealing admixture what reduces the ability of aerial CO2 to dissolve in pore solution and react with lime. The deformation behavior of material has been modified by oil toward the higher toughness, but lower compressive strength, due to polymeration of oil in mortar.

Materials ◽  
2019 ◽  
Vol 12 (17) ◽  
pp. 2694 ◽  
Author(s):  
Shansuo Zheng ◽  
Lihua Niu ◽  
Pei Pei ◽  
Jinqi Dong

In order to evaluate the deterioration regularity for the mechanical properties of brick masonry due to acid rain corrosion, a series of mechanical property tests for mortars, bricks, shear prisms, and compressive prisms after acid rain corrosion were conducted. The apparent morphology and the compressive strength of the masonry materials (cement mortar, cement-lime mortar, cement-fly ash mortar, and brick), the shear behavior of the masonry, and the compression behavior of the masonry were analyzed. The resistance of acid rain corrosion for the cement-lime mortar prisms was the worst, and the incorporation of fly ash into the cement mortar did not improve the acid rain corrosion resistance. The effect of the acid rain corrosion damage on the mechanical properties for the brick was significant. With an increasing number of acid rain corrosion cycles, the compressive strength of the mortar prisms, and the shear and compressive strengths of the brick masonry first increased and then decreased. The peak stress first increased and then decreased whereas the peak strain gradually increased. The slope of the stress-strain curve for the compression prisms gradually decreased. Furthermore, a mathematical degradation model for the compressive strength of the masonry material (cement mortar, cement-lime mortar, cement-fly ash mortar, and brick), as well as the shear strength attenuation model and the compressive strength attenuation model of brick masonry after acid rain corrosion were proposed.


2016 ◽  
Vol 827 ◽  
pp. 267-270 ◽  
Author(s):  
Magdaléna Šefflová ◽  
Tereza Pavlů

This paper is focused on the mechanical properties development of fine recycled aggregate (FRA) concrete. FRA was obtained from recycling plant in the Czech Republic. There were prepared four concrete mixtures in the laboratory. The first mixture was reference (REF) with fine natural aggregate (FNA). FNA was replaced in concrete mixtures R10, R20 and R30 in varying replacement ratio. The concrete mixtures R10, R20 and R30 contained 10 %, 20 % and 30 % FRA. There were tested properties of concrete. Finally, it is possible to say that the use of the FRA in concrete influences concrete properties. It is necessary to verify of probably an improvement of compressive strength of FRA concrete in future research. However, FRA concrete is possible to be used in the manufacturing of building structures, but it is necessary to test durability and lifespan of FRA concrete.


2020 ◽  
Vol 2020 ◽  
pp. 1-8 ◽  
Author(s):  
Tuan Anh Nguyen

One of the main disadvantages of epoxy resins is brittleness and flammability, which is one of the biggest threats and the reason for limiting advanced applications. In this study, Epikote 240 (EP) epoxy resin was plasticized with epoxidized flaxseed oil (ELO) at different concentrations (EP/ELO ratios 95/5; 90/10; 85/15; 80/20; 75/25). Then, nanoclay additives and MWCNTs are simultaneously dispersed into the EP/ELO blend by using ultrasonic vibration. The dispersion of ELO and nanoclay additives (nanoclay and MWCNTs) in epoxy resin is observed by using the scanning electron microscope in combination with the XRD method. The effect of ELO, nanoadditives on mechanical properties, and flame retardants is assessed by tensile strength, flexural strength, compressive strength, impact resistance, UL 94HB method, and limiting oxygen index. Experimental results have shown that the mixing ratio of 90/10 w/w is the ratio for good compatibility, high mechanical properties, and fire retardation compared with other ratios. When adding MWCNTs as well as nanoclay I.30E to Epikote 240 epoxy, the mechanical strength and fire resistance have changed greatly: tensile strength of 85.45 MPa, flexural strength of 116.32 MPa, compressive strength of 189.25 MPa, impact resistance Izod of 24.37 kJ/m2, and fire resistance reached at V1.


2020 ◽  
Vol 14 (2) ◽  
pp. 6734-6742
Author(s):  
A. Syamsir ◽  
S. M. Mubin ◽  
N. M. Nor ◽  
V. Anggraini ◽  
S. Nagappan ◽  
...  

This study investigated the combine effect of 0.2 % drink cans and steel fibers with volume fractions of 0%, 0.5%, 1%, 1.5%, 2%, 2.5% and 3% to the mechanical properties and impact resistance of concrete. Hooked-end steel fiber with 30 mm and 0.75 mm length and diameter, respectively was selected for this study.  The drinks cans fiber were twisted manually in order to increase friction between fiber and concrete. The results of the experiment showed that the combination of steel fibers and drink cans fibers improved the strength performance of concrete, especially the compressive strength, flexural strength and indirect tensile strength. The results of the experiment showed that the combination of steel fibers and drink cans fibers improved the compressive strength, flexural strength and indirect tensile strength by 2.3, 7, and 2 times as compare to batch 1, respectively. Moreover, the impact resistance of fiber reinforced concrete has increase by 7 times as compared to non-fiber concretes. Moreover, the impact resistance of fiber reinforced concrete consistently gave better results as compared to non-fiber concretes. The fiber reinforced concrete turned more ductile as the dosage of fibers was increased and ductility started to decrease slightly after optimum fiber dosage was reached. It was found that concrete with combination of 2% steel and 0.2% drink cans fibers showed the highest compressive, split tensile, flexural as well as impact strength.    


2012 ◽  
Vol 4 (1) ◽  
pp. 1
Author(s):  
Djoko Purwanto

Timber Acacia mangium (Acacia mangium, Willd) for Furniture. The study aims to determine the mechanical and physical properties and the decorative value (color and fiber) wood of acacia mangium with using finishing materials. This type of finishing material used is ultran lasur natural dof ,ultran lasur classic teak, aqua politur clear dof, aqua politur akasia dan aqua politur cherry. After finishing the wood is stored for 3 months. Test parameters were observed, namely, physical and mechanical properties of wood, adhesion of finishing materials, color and appearance of the fiber, and timber dimensions expansion. The results showed that the mechanical physical properties of acacia wood qualified SNI. 01-0608-89 about the physical and mechanical properties of wood for furniture, air dry the moisture content from 13.78 to 14.89%, flexural strength from 509.25 to 680.50 kg/cm2, and compressive strength parallel to fiber 342.1 - 412.9 kg/cm2. Finishing the treatment process using five types of finishing materials can increase the decorative value (color and fiber) wood. Before finishing the process of acacia mangium wood has the appearance of colors and fibers and less attractive (scale scores 2-3), after finishing acacia wood fibers have the appearance of colors and interesting and very interesting (scale 4-5).Keywords: mangium wood, mechanical properties, decorative value, finishing, furniture.


2018 ◽  
Vol 1 (1) ◽  
pp. 77-90
Author(s):  
Walaa Abdelaziem ◽  
Atef Hamada ◽  
Mohsen A. Hassan

Severe plastic deformation is an effective method for improving the mechanical properties of metallic alloys through promoting the grain structure. In the present work, simple cyclic extrusion compression technique (SCEC) has been developed for producing a fine structure of cast Al-1 wt. % Cu alloy and consequently enhancing the mechanical properties of the studied alloy. It was found that the grain structure was significantly reduced from 1500 µm to 100 µm after two passes of cyclic extrusion. The ultimate tensile strength and elongation to failure of the as-cast alloy were 110 MPa and 12 %, respectively. However, the corresponding mechanical properties of the two pass CEC deformed alloy are 275 MPa and 35%, respectively. These findings ensure that a significant improvement in the grain structure has been achieved. Also, cyclic extrusion deformation increased the surface hardness of the alloy by 49 % after two passes. FE-simulation model was adopted to simulate the deformation behavior of the material during the cyclic extrusion process using DEFORMTM-3D Ver11.0. The FE-results revealed that SCEC technique was able to impose severe plastic strains with the number of passes. The model was able to predict the damage, punch load, back pressure, and deformation behavior.


2020 ◽  
Vol 38 (10A) ◽  
pp. 1522-1530
Author(s):  
Rawnaq S. Mahdi ◽  
Aseel B. AL-Zubidi ◽  
Hassan N. Hashim

This work reports on the incorporation of Flint and Kaolin rocks powders in the cement mortar in an attempt to improve its mechanical properties and produce an eco-friendly mortar. Flint and Kaolin powders are prepared by dry mechanical milling. The two powders are added separately to the mortars substituting cement partially. The two powders are found to improve the mechanical properties of the mortars. Hardness and compressive strength are found to increase with the increase of powders constituents in the cement mortars. In addition, the two powders affect water absorption and thermal conductivity of the mortar specimens which are desirable for construction applications. Kaolin is found to have a greater effect on the mechanical properties, water absorption, and thermal conductivity of the mortars than Flint. This behavior is discussed and analyzed based on the compositional and structural properties of the rocks powders.


Energies ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2303
Author(s):  
Congyu Zhong ◽  
Liwen Cao ◽  
Jishi Geng ◽  
Zhihao Jiang ◽  
Shuai Zhang

Because of its weak cementation and abundant pores and cracks, it is difficult to obtain suitable samples of tectonic coal to test its mechanical properties. Therefore, the research and development of coalbed methane drilling and mining technology are restricted. In this study, tectonic coal samples are remodeled with different particle sizes to test the mechanical parameters and loading resistivity. The research results show that the particle size and gradation of tectonic coal significantly impact its uniaxial compressive strength and elastic modulus and affect changes in resistivity. As the converted particle size increases, the uniaxial compressive strength and elastic modulus decrease first and then tend to remain unchanged. The strength of the single-particle gradation coal sample decreases from 0.867 to 0.433 MPa and the elastic modulus decreases from 59.28 to 41.63 MPa with increasing particle size. The change in resistivity of the coal sample increases with increasing particle size, and the degree of resistivity variation decreases during the coal sample failure stage. In composite-particle gradation, the proportion of fine particles in the tectonic coal sample increases from 33% to 80%. Its strength and elastic modulus increase from 0.996 to 1.31 MPa and 83.96 to 125.4 MPa, respectively, and the resistivity change degree decreases. The proportion of medium particles or coarse particles increases, and the sample strength, elastic modulus, and resistivity changes all decrease.


Polymers ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 698
Author(s):  
Selin Sökmen ◽  
Katja Oßwald ◽  
Katrin Reincke ◽  
Sybill Ilisch

High compatibility and good rubber–filler interactions are required in order to obtain high quality products. Rubber–filler and filler–filler interactions can be influenced by various material factors, such as the presence of processing aids. Although different processing aids, especially the plasticizers, and their effects on compatibility have been investigated in the literature, their influence on rubber–filler interactions in highly active filler reinforced mixtures is not explicit and has not been investigated in depth. For this purpose, the influence of treated distillate aromatic extract (TDAE) oil content and its addition time on interactions between silica and rubber chains were investigated in this study. Rubber–filler and filler–filler interactions of uncured and cured silica-filled SBR/BR blends were characterized by using rubber layer L concept and dynamic mechanical analysis, whereas mechanical properties were studied by tensile test and Shore A hardness. Five parts per hundred rubber (phr) TDAE addition at 0, 1.5, and 3 min of mixing were characterized to investigate the influence of TDAE addition time on rubber–filler interactions. It was observed that addition time of TDAE can influence the development of bounded rubber structure and the interfacial interactions, especially at short time of mixing, less than 5 min. Oil addition with silica at 1.5 min of mixing resulted in fast rubber layer development and a small reduction in storage shear modulus of uncured blends. The influence of oil content on rubber–filler and filler–filler interactions were investigated for the binary blends without oil, with 5 and 20 phr TDAE content. The addition of 5 phr oil resulted in a slight increase in rubber layer and 0.05 MPa reduction in Payne effect of uncured blends. The storage tensile modulus of vulcanizates at small strains decreased from 13.97 to 8.28 MPa after oil addition. Twenty parts per hundred rubber (phr) oil addition to binary blends caused rubber layer L to decrease from 0.45 to 0.42. The storage tensile modulus of the vulcanizates and its reduction with higher amplitudes were incontrovertibly high among the vulcanizates with lower oil content, which were 13.57 and 4.49 MPa, respectively. When any consequential change in mechanical properties of styrene–butadiene rubber (SBR)/butadiene rubber (BR) blends could not be observed at different TDAE addition time, increasing amount of oil in blends enhanced elongation at break, and decreased Shore A hardness and tensile strength.


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.


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