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Fracture properties of concrete are mainly influenced by specimen shape, size and type of testing method. The study aims to identify the characteristic divergence in fracture – evaluating testing methods, i.e. three-point bend test and wedge splitting test for fibrous self-compacting concrete.

A total of nine mixes with three different coarse aggregate sizes (20, 16 and 12.5mm) and three coarse to fine aggregate quantities (40–60, 45–55 and 50–50) were considered to examine the influence of materials on fracture parameters of fibrous self-compacting concrete. For three-point bend test, size effect method was considered to analyze the fracture properties.

The experimental investigation revealed that fracture energy calculated from wedge splitting test was reasonably on higher side for maximum coarse aggregate-based specimens for all coarse to fine aggregate quantities, while for the size effect method, fracture energy value was maximum for least coarse aggregate sized specimens.

The fracture properties of fibrous self-compacting concrete obtained from wedge splitting test method was higher than the size effect method. This is due to the consideration of only peak load for determining the fracture properties in size effect method analysis.

Identifying stone decay forms is an essential first step in stone conservation. In this study a visually based geomorphological approach was used to provide a rapid assessment of the general weathering characteristics displayed by building sandstones in Stoke‐on‐Trent. Stone decay was found to be largely caused by the mechanical disruption of the sandstone and its occurrence was extremely variable in both space and time. The study demonstrates the close interrelationship between stone properties, environmental conditions, morphology of weathering features, and building characteristics. It is important that these close and dynamic interrelationships are recognised when seeking to explain or predict stone behaviour for management purposes.

Corrosion failures due to condensing flue gases containing H₂O, SO₃, NO_x and HCl still occur more often than might be expected. The corrosion failures can be of several types: general corrosion, pitting attack and stress corrosion cracking (SCC). The chemistry of condensing gases is discussed, and some examples of corrosion in large‐scale installations are presented, including blast stoves for steel production, heat recovery steam generators, and waste incineration boilers. The use of thermal insulation inside boiler casings can result in nitrate SCC when the flue gas contains high concentrations of NO_x. Nitric acid from flue gas can react with carbon steel and insulation material forming ammonium nitrate and calcium nitrate. Both materials have hygroscopic properties and are very corrosive, even above the water dewpoint of the gases.

This work seeks to present a systematic study that aimed to provide quantitative understanding of the fundamental factors that influence the chloride threshold of pitting corrosion of steel in concrete, by conducting a set of laboratory tests to assess the corrosion potential (E_corr) and pitting potential (E_pit) of steel coupons in simulated concrete pore solutions.

With the aid of artificial neural network, the laboratory data were used to establish a phenomenological model correlating the influential factors (total chloride concentration, chloride binding, solution pH, and dissolved oxygen (DO) concentration) with the pitting risk (characterized by E_corr−E_pit). Three‐dimensional response surfaces were then constructed to illustrate such predicted correlations and to shed light on the complex interactions between various influential factors.

The results indicate that the threshold [Cl⁻]/[OH⁻] of steel rebar in simulated concrete pore solutions is a function of DO concentration, pH and chloride binding, instead of a unique value.

The limitations and implications of the research findings were also discussed.

This research could have significant practical implications in predicting the service life of new or existing reinforced concrete in chloride‐laden environments.

This study further advances the knowledge base relevant to the chloride‐induced corrosion of steel rebar in concrete.

To investigate the mechanical properties of geopolymer concrete at elevated temperatures.

The investigation involved studying the influence of partially replacing fly ash with ground granulated blast furnace slag (GGBS) at different proportions (5%, 10%, 15%, 20% and 25%) on the composition of the geopolymer. This approach aimed to examine how the addition of GGBS impacts the properties of the geopolymer material. The chemical NaOH was purchased from the local supplier of Jamshedpur. The alkali solution was prepared with a concentration of 12 M NaOH to produce the concrete. After several trials, the alkaline-to-binder ratio was determined to be 0.43.

The compressive strength values at 28 days for specimens FG1, FG2, FG3, FG4 and FG5 are 35.42 MPa, 41.26 MPa, 44.79 MPa, 50.51 MPa and 46.33 MPa, respectively. The flexural strength values at 28 days for specimens FG1, FG2, FG3, FG4 and FG5 are 5.31 MPa, 5.64 MPa, 6.12 MPa, 7.15 MPa and 6.48 MPa, respectively. The split tensile strength values at 28 days for specimens FG1, FG2, FG3, FG4 and FG5 are 2.82 MPa, 2.95 MPa, 3.14 MPa, 3.52 MPa and 3.31 MPa, respectively.

This approach allows for the examination of how the addition of GGBS affects the properties of the geopolymer material. Four different temperature levels were chosen for analysis: 100 °C, 300 °C, 500 °C and 700 °C. By subjecting the geopolymer samples to these elevated temperatures, the study aimed to observe any changes in their mechanical.

The purpose of this paper is to study and analyze the effects of fly ash (FA) as a mineral admixture on compressive strength (CS), carbonation resistance and corrosion resistance of reinforced concrete (RC). In addition, the utilization of inexpensive and abundantly available FA as a cement replacement in concrete has several benefits including reduced OPC usage and elimination of the FA disposal problem.

Reinforcement corrosion and carbonation significantly affect the strength and durability of the RC structures. Also, the utilization of FA as green corrosion inhibitors, which are nontoxic and environmentally friendly alternatives. This review discusses the effects of FA on the mechanical characteristics of concrete. Also, this review analyzes the impact of FA as a partial replacement of cement in concrete and its effect on the depth of carbonation in concrete elements and the corrosion rate of embedded steel as well as the chemical composition and microstructure (X-ray diffraction analysis and scanning electron microscopy) of FA concrete were also reviewed.

This review provides a clear analysis of the available study, providing a thorough overview of the current state of knowledge on this topic. Regarding concrete CS, the findings indicate that the incorporation of FA often leads to a loss in early-age strength. However, as the curing period increased, the strength of fly ash concrete (FAC) increased with or even surpassed that of conventional concrete. Analysis of the accelerated carbonation test revealed that incorporating FA into the concrete mix led to a shallower carbonation depth and slower diffusion of carbon dioxide (CO₂) into the concrete. Furthermore, the half-cell potential test shows that the inclusion of FA increases the durability of RC by slowing the rate of steel-reinforcement corrosion.

This systematic review analyzes a wide range of existing studies on the topic, providing a comprehensive overview of the research conducted so far. This review intends to critically assess the enhancements in mechanical and durability attributes (such as CS, carbonation and corrosion resistance) of FAC and FA-RC. This systematic review has practical implications for the construction and engineering industries. This can support engineers and designers in making informed decisions regarding the use of FA in concrete mixtures, considering both its benefits and potential drawbacks.

The purpose of this paper is to prepare heat insulating exterior emulsion coating and to study its heat insulating property along with mechanical, chemical and weathering resistance properties with varying amount of hollow glass microspheres and cenospheres.

For heat insulating effect, various compositions were made by incorporating different proportions of hollow glass microspheres (HGM) and cenospheres (C). The mechanical, chemical, morphological and optical properties of the coating films were studied and compared.

Addition of hollow glass microspheres and cenospheres enhanced heat insulating property of the coating, hardness, tensile strength and wet scrub resistance. It was evaluated that optimum loading for both cenospheres and hollow glass microspheres was 10 wt.% and both the systems showed good mechanical, chemical resistance and weathering properties.

Addition of hollow glass microspheres and cenospheres to acrylic emulsion coating is a simple and inexpensive method.

The new heat insulating coatings with good thermal insulation properties and improved weather resistance were prepared. These coatings could find applications in demanding fields such as exterior wall coatings and roof coatings.

The purpose of this paper is to develop a conceptual framework of fly ash (FA) handling by using the total interpretive structural modeling (TISM) technique in the Indian context.

The conceptual framework of the FA handling technique has been developed by using the TISM technique, where the FA handling factors have been identified from literature and verified by experts.

The conceptual framework of FA handling technique developed by using TISM contributes to the development of FA handling hierarchy. The framework identifies that there are 12 important factors which play a vital role in FA handling. The conceptual model indicates that particle size distribution derives FA handling technology.

This study identified important factors for FA handling and it has implication for both organizations and policy makers. This study delivers the factors which play an important role in handling FA in a thermal power plant. This study highlights important linkages essential for the expansion of FA handling technologies and policies.

This study is unique in itself as it studies the FA handling factors through the qualitative modeling technique and has made its contribution in FA handling by providing the conceptual framework for managing FA in the thermal power plant.

The purpose of this technical paper is to investigate the friction and wear behaviour of heat treated Al 6061 alloy and Al 6061 SiC‐graphite particulate reinforced hybrid composites subjected to different ageing durations.

The composites have been prepared by stir casting process with varying percentages of SiC and graphite particles. The cast 6061 alloy and its composites were subjected to solutionising treatment at a temperature of 803 K for 1 hr followed by quenching in water. The quenched samples were then subjected to artificial ageing for different durations of 4, 6, 8 hr at a temperature of 448 K. Tests were performed on heat treated Al 6061 alloy and its composites using pin‐on‐disc apparatus. Hardness measurements were also made on the specimens. The wear surfaces of the composites were analyzed using scanning electron microscopy.

During wear test of specimens the wear resistance of the hybrid composites was found to increase with increase in ageing durations. The microscopic examination of the wear surfaces shows that the base alloy and composites wear primarily because of abrasion and delamination. The hardness result shows that the hardness of the composites increased with decreasing weight percentage of graphite particles.

The content of this paper is fully research oriented and the finding from this investigation will be useful for society and also the automobile industries, especially in the making of brake drums.

Environmental issues caused by the production of Portland cement have led to it being replaced by waste materials such as fly ash, which is more economical and safer for the environment. Also, fly ash is a material with sustainable properties. Therefore, this paper aims to focus on the development of sustainable construction materials using 100% high-calcium fly ash and potassium hydroxide (KOH)-based alkaline solution and study the engineering properties of the resulting fly ash-based geopolymer concrete. Laboratory tests were conducted to determine the mechanical properties of the geopolymer concrete such as compressive strength, flexural strength, curing time and slump. In phase I of the study, carbon nanotubes (CNTs) were added to determine their effect on the strength of the geopolymer mortar. The results derived from the experiments indicate that mortar and concrete made with 100% fly ash C require an alkaline solution to produce similar (comparable) strength characteristics as Portland cement concrete. However, it was determined that increasing the amount of KOH generates a considerable amount of heat causing the concrete to cure too quickly; therefore, it is notable to forming a proper bond was unable to form a stronger bond. This study also determined that the addition of CNTs to the mix makes the geopolymer concrete tougher than the traditional concrete without CNT.

Tests were conducted to determine properties of the geopolymer concrete such as compressive strength, flexural strength, curing time and slump. In Phase I of the study, CNTs were studied to determine their effect on the strength of the geopolymer mortar.

The results derived from the experiments indicate that mortar and concrete made with 100% fly ash C require an alkaline solution to produce the same strength characteristics as Portland cement concrete. However, it was determined that increasing the amount of KOH generates too much heat causing the concrete to cure too quickly; therefore, it is notable to forming a proper bond. This study also determined that the addition of CNTs to the mix makes the concrete tougher than concrete without CNT.

This study was conducted at the construction engineering and management concrete laboratory at North Dakota State University in Fargo, North Dakota. All the experiments were conducted and analyzed by the authors.