Partial Replacement of Cement in Concrete with Granite Powder and Fine Aggregate with Saw Dust Ash and Quarry Dust

The partial replacement of cement and fine aggregate with granite powder and saw dust ash, quarry dust when it is able for sustainable development is characterized by application, we came to know that a lot of damage is done to environment in the manufacturing of cement that the ton of cement manufacture releases half ton of co2 and control of the granite powder same way granite powder and saw dust is cheaper in cost. In this investigation of granite slurry and saw dust was used to partial substitute in proportions varying from 10%, 20%, 30% by weight to cement in concrete and tested from compressive strength, tensile strength and flexure strength. Concrete cubes measuring. 150 x 150 x 150 mm were cast and their compressive strength, tensile strength and flexure strength is evaluation at 7, 14, 21, 28 days. It was observed that replacement at 10% of cement by weight with granite powder in concrete was the most effective in increasing compressive and flexural strength compare to other ratios. The test results were plotted for 10% ratio of granite slurry and saw dust having great compressive strength, tensile strength and flexure strength compared to 20%, 30% ratio. So it can be concluded that when locally available granite slurry and saw dust is a good partial replacement to concrete and improves compressive, tensile, workability, flexure characteristics of concrete, while simultaneously offsetting the overall cost of concrete substantially. Keywords: Granite waste, saw dust ash, sound absorption, compressive strength, flexibility, workability, Quarry Dust.

The Tensile and Flexural Forces of Acropora Reef Waste Particulate-Enchanced Polyester Composites

Composite is a material that combines two or more materials that basically dissimilar chemical or physical properties from one another. In this research, we used Acropora coral reef waste particulate and Resin Polyester BQTN type 157 with Methyl ethyl ketone peroxide (MEKP) 1% as the hardener. The Hand Lay-Up molding technique is used in the process of making the material. The tensile and flexure test is done according to the ASTM D3090 and ASTM D790 – 03 standards. The purpose of this research is to discover the means to produce a composite enhanced by Acropora coral reef waste with polyester matrix and to learn the tensile and flexure strength from the Acropora coral reef waste particulate-enhanced polyester composites with mass fraction varieties of 10%, 20%, 30%, and 40%. The tensile test result of Acroporal coral reef waste particulate with polyester matrix yields average tensile strength at mass fraction variety of 40% with a score of 19,66 MPa, with an Modulus score of 636,75 MPa. The flexure test result of Acropora coral reef waste particulate with polyester matrix yields average flexure stress at mass fraction variety of 40% with a score of 112,56 MPa, with an average Elastic Modulus score of 3098,96 MPa.

Mechanical Properties of Modified Engineered Cementitious Composites (MECC) Incorporating Marble Dust

Engineered cementitious composites (ECC) are a type of high-performance fiber reinforced cementitious composite. ECC has different applications in the construction field due to its inherent characteristics of high tensile strain. The main concern regarding ECC is its high cost. The content of cement is high contributing to its cost. In this research work, the cement in ECC is replaced with marble dust and its mechanical properties such as compressive strength and flexure strength have been assessed. For this purpose, both cubes and cylinders were tested at different test ages for finding the compressive strength development with time and observe the shape effect of specimens on the compressive strength of ECC mixes. Beam members were tested for finding the flexure strength of ECC mixes. Deflection gauge was also installed at the mid span on the bottom surface of the beams to find the maximum mid span deflection before failure. The compression test results of both cylinders and cubes revealed that using of marble dust has negative effect on the compressive strength of ECC. The flexure strength result showed that marble dust can be used up to some extent replacing cement will increase the flexure strength. The result of mid span deflection suggests that by incorporating marble dust in ECC, its ductility increases.

Study on Glass Fibre Concrete Roof Tiles

The main objective of the fibre glass in concrete roof tile is to obtain good strength, heat resistant, & water seepage resistant roof tile. To ensure that the roof tile produced plays a role development with minimum cost, and high flexure strength. To draw an analogy between the normal concrete roof tile with glass fibre concrete roof tile. The sizes of short fibres used were 25mm and the glass fibres were alkali resistant. The effect of these short fibres on wet transverse strength, compressive strength and water absorption was carried out.

Influence of the Printing Angle and Load Direction on Flexure Strength in 3D Printed Materials for Provisional Dental Restorations

The CAD/CAM techniques, especially additive manufacturing such as 3D printing, constitute an ever-growing part of obtaining different dental appliances and restorations. Of these, provisional restorations are of frequent use in daily dental practice and are the object of this study. Masticatory and parafunctional forces determine flexure on these prostheses. This study investigates the influence of the printing angle and loading direction of the applied force on the flexure strength of two commercially available printable resins—Detax Freeprint Temp and Nextdent MFH Vertex dental. Ten rectangular beam specimens printed at the angle of 0, 45 and 90 degrees were fabricated of each of these materials, with an addition of 10 at 0 degrees for the investigation of the load direction. Three-point bending tests were performed in a universal testing machine. Flexure strength, strain at break and Young’s modulus were determined and a statistical analysis was performed on the obtained data. According to the statistical analysis, the flexural strength has a significance dependence with respect to degrees of orientation, for both investigated materials.

Flexural Behavior of 3D printed Concrete Beam with Fiber Reinforcement

3D printing with concrete is a promising new method for rapid, low cost construction. The flexural strengths for reinforced/unreinforced and 3D printed/cast concrete Warren trusses were tabulated and the failure mechanisms were reported. The types of reinforcement used were rebar(basalt and steel), and mesh (basalt and aramid). The effect of loading geometry and loading speed was measured for basalt mesh and aramid mesh composite, respectively. Due to the expected variation in flexure between samples, it cannot be said whether small differences for various tests are significant. Variation stems from a microscopically uneven surface and random inhomogeneities in the bulk of the tested material which act as a microcrack catalyst and propagator. Since the tested beams are short specimens the numerical findings of other studies will vary based on the intended design. This paper is intended to assess the performance of various reinforcements in a qualitative sense by comparing basalt reinforcement with other reinforcements. It was found that cast beams tolerated deflection better but had a similar flexure strength compared as the printed beams. The steel and basalt rebar reinforced beams had the highest flexure strengths where the traditional steel rebar reinforcement outperformed the basalt in flexure by 36% and the basalt outperformed the steel in deflection by 40%. The basalt mesh outperformed the cast and printed unreinforced bars by a small margin but had only 25% of steel rebars’ deflection at maximum flexure strength. The aramid mesh tolerated the biggest deflection out of any sample at 2.26 cm.

Effect of Dry–Wet Cycle Periods on Properties of Concrete under Sulfate Attack

Dry–wet cycle conditions have significant effects on the corrosion of concrete under sulfate attack. However, previous studies have only applied them as a method for accelerating sulfate attack and not systematically studied them as an object. In order to explore the impact of sulfate attack with different dry–wet cycle periods on concrete, in this study, four dry–wet cycle periods (3, 7, 14, and 21 days) were selected. The flexure strength, relative dynamic modulus, and mass were tested, and the microstructures of the eroded specimens were also analyzed. The intensity and depth of sulfate erosion were influenced by the wet–dry cycle period. The results show that the deterioration of concrete first increased and then decreased with an extension of the dry–wet cycle period. Microstructural analysis indicated that, with an increase in the dry–wet cycle period, the corrosion depth of sulfate attack increased. Moreover, the erosion products such as ettringite and gypsum were greatly increased, in agreement with the macroscopic variations. However, excessively prolonging the dry–wet periods does not significantly further the deterioration of concrete’s performance. Therefore, considering the strength and depth of corrosion caused by sulfate attack, it would be appropriate to employ dry–wet cycle periods of 7–14 days under natural dry conditions in studies on concrete.

Effect of Streptococcus mutans on surface-topography, microhardness, and mechanical properties of contemporary resin composites

Objective: Dental caries is the most prevalent disease globally, and Streptococcus mutans ( S. mutans) is a common associated oral bacteria. Additionally, S. mutans possess esterase activity capable of degrading resin composites (RC). However, the effect of degradation on the physical-mechanical properties of the RC has not been extensively studied. We evaluated the flexure strength (FS), the diametral tensile strength (DTS), the modulus of elasticity (ME), and the microhardness of three contemporary RC to establish if S. mutans could affect them. Methods: One hundred thirty-eight bar-shaped and 276 disc-shaped specimens were fabricated with Enamel Plus HRi, IPS Empress Direct, and Clearfil AP-X, and physical-mechanical testing was done after been incubated during 30 and 60 days in culture media with or without S. mutans. Also, a scanning electron microscope was used to identify surface changes. Results: None of the tested RC were affected in their mechanical properties (FS, ME, and DTS). However, Clearfil AP-X and Enamel Plus HRI showed eroded surfaces and a decreased microhardness after 30 and 60 days S. mutans incubation. IPS Empress Direct presented the lowest values in all the tests, but its physical-mechanical features and surface were not affected by bacteria’s exposure. Conclusions: Exposure to S. mutans could affect some contemporary RC; however, the effect seems superficial since its mechanical features were not affected.

Mechanical Properties of PVA & Steel Hybrid Fiber Reinforced Concrete

Combining various kinds of fibre to achieve good response and strength from the concrete by using different experiments is shown in this research. Here PVA which is polyvinyl alcohol and HS hooked end steel fibres are used to gain more strength compared with normal concrete or single fibre concrete. Here first we take PVA specimens results by considering optimum dosage 0.15% result & HS fibre is taken as HFRC concrete by this the strength of the concrete can control the crack behavior occurred in specimens. Mechanical properties such as compressive strength test, flexure strength, and stress-strain behavior are studied. Combining different fibers HFRC is mainly useful for longstanding structures. This method can be easy to understand and economical.