Tons Of Concrete Research Articles

Assessment Of Industrial Waste and Additives Materials Use in The Sustainable Design of Concrete

The sustainable design of concrete is of paramount importance in the construction industry as it strives to minimize environmental impact while maintaining performance and durability. A key aspect of this endeavor is the assessment and integration of industrial waste materials and additives into concrete formulations. Concrete is the most frequently used construction material in the world. Each year, over ten billion tonnes of concrete are produced, resulting in the depletion of natural resources and a colossal carbon footprint. One of the primary objectives of contemporary concrete technology is to reduce the use of Portland cement and natural fine aggregates by partially substituting them with various waste materials and industrial byproducts. This paper summarises the findings of a study in which steel slag aggregate, silica fume and glass refuse were successfully used to partially replace river sand and Portland cement.

Experimental study on recycled coarse aggregate of concrete

After water, concrete is the second most consumed substance on the earth, and its extensive use serves as the foundation for the urbanisation of the planet. Additionally, concrete facilitates the growth of metropolitan zones. Approximately 25 billion tonnes of concrete are produced annually on a global scale, according to estimates. The manufacture of concrete requires a growing quantity of aggregate, while the current supply is decreasing. Therefore, it is vital that new aggregate sources be identified. Recycling concrete is growing in importance as it conserves natural resources and reduces the need for disposal by utilising readily available concrete as a source of aggregate for the manufacture of fresh concrete. Due to the fact that recycling concrete conserves natural resources and avoids the need for disposal, this is the case. It is often believed that the use of demolished concrete as a substitute for natural aggregate might lead to numerous issues. This is because all emerging nations are concentrating on the creation of ecologically friendly technology. However, according to a previous study, the use of recycled concrete results in a decrease in the concrete's strength as well as other characteristics. The incorporation of aggregate as one of the basic components in the production of concrete is crucial to the operation. 35 to 40 percent of the entire concrete mixture consists of coarse aggregate. The qualities of the aggregates utilised in the production of concrete also have an effect on the final strength of the concrete. As part of this programme, demolished concrete from a field is collected, reused through a few easy steps to improve its qualities, and then used to produce new concrete. It was discovered that reborn concrete with 100 percent, 75 percent, and 50 percent replacement of aggregate (RCA) at 7 days, 14 days, and 28 days exhibited higher compressive strength than conventional concrete. This was discovered by comparing resurrected concrete to conventional concrete.

Applicability and limitations of using seawater and sea sand in concrete

The concrete Industry is responsible for the large consumption of raw materials, such as limestone, potable water, steel, and sand, knowing that consuming these materials comes with large economic and environmental costs. Millions of tons of concrete are produced annually, requiring a significant quantity of water. Given the scarcity of fresh water (only 3% of the total water on earth), using seawater as an alternative can greatly conserve potable water. Similarly, replacing natural sand with sea sand can also help conserve natural resources. Consequently, using seawater and sea sand in concrete gained significant attention worldwide, particularly in countries with limited freshwater supply. Much research has been conducted on concrete produced with seawater and sea sand. Whereas seawater is beneficial in some aspects, it can enhance the free chloride content in concrete increasing the corrosion vulnerability. In this paper, the beneficial effects of using seawater and sea sand in concrete have been reviewed. The resulting mechanical, hydration, and durability properties have been assessed and compared with ordinary concrete. The focus has been not only on the material properties but also on the structural attributes. Prospects, challenges, and limitations have also been discussed. The study serves as a basis for efficiently using seawater and sea sand in concrete for sustainable development.

Experimental investigation of construction & demolition waste in bituminous concrete

India is a developing nation, and developing nations need a lot of construction. In 2022, the construction industry used 2.05 billion tonnes of coarse materials. To meet the need for houses and roads, the 12th Five Year Plan forecasts an additional 1 billion tonnes of concrete by 2027. In road mix ratios, coarse aggregates range from 2 to 10 parts per unit of cement. The demand for coarse aggregate in 2027 will range from 2.1 to 10.3 billion tonnes. In construction, aggregate is a useful building material. Since building and demolition debris make up a significant portion of landfill garbage, it is important to establish strategies to ensure that it is used effectively. The present study has made an attempt to use recycled aggregates as coarse aggregates and concrete debris as fine aggregates as a partial replacement for natural aggregate. The experimentation includes the characterization of materials, volumetric analysis, marshal stability, flow value, indirect tensile strength, and tensile strength ratio. 20% replacement of natural aggregates with construction and demolished waste has been proposed in the concluding remarks.

Usage potential and benefits of processed coconut shells in concrete as coarse aggregates

As concrete consumes a lot of natural resources, sustainable growth is challenging. Around the world, 7.23 billion tonnes of concrete is produced annually, necessitating a significant quantity of aggregates to meet construction demands. Therefore, it is crucial to explore alternatives to coarse aggregates, which make up roughly 70–80% of the overall volume of the concrete. Additionally, waste management is a global concern that is exacerbated by up to 15% due to coconut shell trash. India ranked third in the world for coconut production in 2018, is particularly affected by this issue. This study investigates the usage of coconut shells in place of coarse aggregate. Owing to the high-water absorption of coconut shells, presoaked coconut shells were replaced as coarse aggregate with 5, 10, 15, 20, and 25% in M30 grade concrete. Slump, density, compressive strength, and microstructural characteristics were studied and evaluated. It is observed that, due to the presence of the plain surface on one side of the coconut shell, the workability of the concrete increased as the percentage of coconut shells increased. Because of the lower specific gravity of coconut shells, concrete produced by 15% replacement of coarse aggregates, reduced the density of the concrete by 7% when compared to the conventional concrete. The 28-day compressive strength of 15% coconut shell replaced concrete showed a 24% strength reduction compared to conventional concrete. C-S-H gel formation was evident from SEM analysis. It is important to note that the compressive strength of coconut shell aggregate concrete at 3, 7, 14, and 28 days, decreased rapidly beyond the 15% replacement of coarse aggregates. It has been found that concrete may be produced without impacting performance qualities when coconut shell aggregates are used in place of natural aggregates at an optimal replacement of 15%.

A case study for exploring the alkali-aggregate reactivity of Cyprus aggregates

Concrete is the most commonly used construction material in Cyprus Island as it is all around the world. Even though thousands of tons of concrete are manufactured in both North and South Cyprus, the alkali-aggregate reactivity (AAR) of the crushed (quarried) aggregates has not been previously investigated in a systematic way. The lack of information on the AAR likelihood of Cyprus aggregates in the related literature has caused a lack of awareness about this durability problem in the island and hence, sufficient controls for taking necessary levels of precautions could not be made over the past decades. Two aggregate samples from North Cyprus and another type of aggregates from South Cyprus were obtained from active quarries and tested within this case study for the first time with RILEM tests in order to verify the likelihood of both alkali-silica and alkali-carbonate reactivities of Cyprus Aggregates. The results obtained from RILEM tests and the supplementary SEM analysis showed that both the North (limestone) and South (diabase) Cyprus aggregates exhibit significant levels of alkali-silica reactivity when they are used with composite cement, which is commonly preferred for its advantages. Results also indicated that the mortar batch including the second type of North Cyprus aggregates (dolomitic limestone) with the mentioned cement is potentially reactive for alkali-carbonate reaction as well. The experimental information provided for the first time with this case study is critical both for further Cyprus durability research studies to be carried out and also for improving the quality of local construction activities.

Determination of properties and environment due to the usage of Flyash and Marble waste Powder in concrete

The main problem in Developing Countries like India, concrete is commonly used as a building material. Every year, around 12 billion tonnes of concrete are produced. Approximately 18 million tonnes of concrete are expected to be produced annually by 2050, according to current estimates. As a result of this sudden growth in concrete use during the past decade, the consumption of cement has surged dramatically. At the moment, 4,000,000 thousand metric tonnes of cement are produced annually, accounting for almost 5% of all pollution that’s leading to global warming. It is estimated that the generation of Flyash and marble waste powder (MWP) accounts for a major portion of the pollution in developing countries today. Massive amounts of both MWP and Flyash are produced, and their disposal is a major issue in the industry. Given their binding qualities, Properties of concrete improved due to both Flyash and MWP. A mixture of PPC & MWP is used to create environmentally friendly concrete in this study. MWP can substitute fine aggregate up to 30% of the total amount of fine aggregate utilized. Additionally, The Usage of Steel Fibres in 1% to 3% is done. A significant increase in cost is indicated by the economic feasibility analysis, However, this is in exchange for a significant increase mechanical property of the material, as well as a favorable influence on the environment, which will contribute to long-term development and sustainability.

Role of Geopolymer Concrete with GGBS in Rigid Pavements

Abstract: In modern construction concrete is very expensive and popular material where cement is the main composite. Every year we are producing billion tons of concrete. Production of cement is responsible for too much of CO2 production, in other words it is also responsible for global warming. Mostly India is facing the problem of pollution. Researchers have done a great job and found many ways to replace cement. For making geopolymer concrete by products of different industries may be used like. Fly ash, rice husk. In this investigation geopolymer concrete is prepared with GGBS. GGBS is a by-product of steel industry. It holds the coarse and fine aggregates in the matrix. In this investigation geopolymer concrete is prepared with GGBS and advantages and disadvantages are also investigated. It was an observation that it has good results over other concrete. GGBS is a good replacement of cement and it will help in reducing the production of CO2. as a result of this global warming can be reduced. Keywords: GGBS, Slag, Aggregates, Slump, Geo Polymer

Sustainable design of concrete using industrial additives and wastes

AbstractConcrete is the most widely used construction material in the world. Over ten billion tons of concrete are being produced each year resulting in exhaustion of natural materials and an enormous carbon footprint. One of the primary goals of concrete technology today is to reduce the use of Portland cement and natural fine aggregates by partially replacing them with various waste materials and by-products of industrial processes. The paper summarizes the results of a study where the partial replacement of river sand and Portland cement was successfully applied using steel slag aggregate, silica fume and glass waste.

COMPUTATIONAL ARRANGEMENT OF DEMOLITION DEBRIS

The average builder in the USA provides a warrantee for 10 years, and the US Department for Energy calculates that US office buildings have an average lifespan of 73 years. No building is permanent, and all will face demolition at some point. When a building comes to the end of its safe and useful lifespan, there is no method for re-using the material in new buildings, instead, all constructions today require virgin material. This is a problem for sustainability because US cities, like most other global cities, require cyclical replacement of ageing buildings, and therefore perpetual resource extraction. This paper provides techniques for computationally arranging materials after the demolition and unmaking of architecture. Rather than downcycling concrete into low-value aggregate or melting float glass into opaque bottles methods are shown for this material to be indexed, re-machined and algorithmically arranged into new assemblies. These assemblies are conceived of as holding patterns; an indexed library of materials that are put into useful architectural arrangements, but ready to be disassembled towards some future use. These holding patterns are used as infill to the city rather than landfill beyond. Rather than building for sixty-year life spans, the project offers an imagination of eternal re-constructions that can learn from the carcass of past buildings. Based on rough estimates  2016 could be the first year where there exists more than one trillion tons of concrete on earth. More than the total weight of living trees on the planet (Crowther et al. 2015; USGS, 2018). This paper begins to develop new aptitudes for re-fitting misfit material rather than consuming evermore.

Underwater abrasion of steel fiber-reinforced self-compacting concrete

Hundreds of tons of concrete may be ruined due to the abrasion erosion phenomenon that takes place in several hydraulic structures. Such unfavorable action can impose high maintenance costs and reduce the life span of these structures. The high-velocity water flow which carries large amounts of sediments is basically the main cause of this phenomenon. To better understand concrete abrasion in hydraulic structures, an experimental investigation was conducted to study the underwater frictional abrasion of self-compacting concrete (SCC) using the ASTM C1138 test method. Six SCC mixtures were prepared with different design grades of 30, 40 and 50 MPa and different micro-steel fiber contents of 0, 0.5, 0.75 and 1.0%. Four fresh SCC tests were adopted, while abrasion and control tests were conducted at ages of 7, 28 and 90 days. The ASTM C1138 tests showed that increasing the mixture strength by 20 MPa improved the abrasion resistance more effectively than the inclusion of 1.0% of steel fiber. Compared to the 30 MPa plain SCC, the 90-day abrasion resistance improved by 78% for SCC with 50 MPa strength, while the inclusion of 1.0% of micro-steel fiber enhanced the resistance by only 26%.

EXPERIMENTAL INVESTIGATION ON NATURAL FIBER ALONG WITH SILICA FUME IN CONVENTIONAL CONCRETE


 
 
 Concrete is globally recognized for its long term service period in the application of concrete. In the region of five billion tons of concrete are utilized more or less in the planet and increasing every year. In view of the environmental problems faced today considering the fast reduction of natural resources like sand and aggregate. Owing to the growth of Science and Technology in recent decades, there is a modification in the practice of concrete along with some additives as the complement for strength and workability.Basalt Fiber is categorized under the Mineral additive and brought into usage in early 1920’s in the period of World war for Military purposes. Silica fume is hugely known for its durability and it increases the density of concrete. On Another hand, the building are often subjected to risk of corrosion and Sustainability, the application of any element in the proportions of concrete will possess the property of Resisting and rejuvenating the nature of Concrete.
 
 

EXPERIMENTAL INVESTIGATION ON NATURAL FIBER ALONG WITH SILICA FUME IN CONVENTIONAL CONCRETE

Concrete is globally recognized for its long term service period in the application of concrete. In the region of five billion tons of concrete are utilized more or less in the planet and increasing every year. In view of the environmental problems faced today considering the fast reduction of natural resources like sand and aggregate. Owing to the growth of Science and Technology in recent decades, there is a modification in the practice of concrete along with some additives as the complement for strength and workability.Basalt Fiber is categorized under the Mineral additive and brought into usage in early 1920’s in the period of World war for Military purposes. Silica fume is hugely known for its durability and it increases the density of concrete. On Another hand, the building are often subjected to risk of corrosion and Sustainability, the application of any element in the proportions of concrete will possess the property of Resisting and rejuvenating the nature of Concrete.

The Utilization of Recycled Materials for Concrete and Cement Production- A Review

The utilization of recycled materials is one of the seven principles of sustainable construction. These principles based on the efficient use of resources were defined by the International Council of Building in 1994. Recycled materials such as recycled concrete aggregate or recycled brick aggregate from construction and demolition waste, waste glass from municipal waste or recycled waste gypsum from gypsum boards are able to use as replacement of primary raw materials in cement and concrete production. Concrete and cement production totally depends on the natural resources. The world production of concrete has been twelve times increased during last six decades. Nowadays, nearly one ton of concrete is produced each year for every human being in the world on average. On one hand, the use of recycled materials in cement and concrete production helps to reduce raw materials and urban land occupation. However, on the other hand, the recycled materials used as partial replacement of raw materials influence properties of final product. This paper reviews the different uses of recycled materials in cement and concrete production and the effect of the properties of these materials to the cement and concrete quality.

Improving the mechanical performance of cement composites by carbon nanotubes addition

Abstract: The addition of high performance nano materials like carbon fibers, carbon nanotubes, graphene etc. in the cement and concrete is gaining attention for achieving multifunctional composite materials with enhanced mechanical, physical and electrical properties. The nano-metric size range and the exceptionally high mechanical properties of carbon nanotubes possess very great potential for their utilization in cementitious composites for obtaining remarkable properties. Billions of ton of concrete is used every year in construction industry and its quantity may be reduced to a large extent only by improving the mechanical and durability properties. One way of achieving the enhanced mechanical properties of cement composite is the utilization of thoroughly dispersed carbon nanotubes in the composite matrix. In the present research, small fractions of multiwall carbon nanotube (MWCNTs) i.e. 0.05 and 0.10 wt.% of cement have been incorporated into the cement concrete and their influence on the mechanical properties of the resulting composites have been studied. It is a well-known fact that the uniform dispersion of the MWCNTs in the composite matrix holds the key for the performance improvement. Therefore, special attention was paid to this aspect and uniform dispersion of MWCNTs was achieved through the use of high energy sonication in the presence of modified acrylic based polymer (acting as a surfactant). The concrete specimens were tested in splitting tensile, flexure and compressive strength after 3, 7, 28 and 56 days of immersed water curing. It was observed that the addition of 0.05wt.% MWCNTs increased the splitting tensile strength by 20.58%, flexural strength by 26.29% and compressive strength by 15.60% as compared to the control mix at 28 days of curing. The strength enhancements for the concrete mixes containing MWCNTs may be regarded to the phenomenon of bridging, pinning and branching of the cracks at nano/micro level due to the presence of MWCNTs. Beside strength enhancements, it was also observed that the MWCNTs had tremendously enhanced the fracture energy and breaking strains of the concrete mixes as observed in three-point bending tests. The research concludes that very low amounts of MWCNTs incorporated in the cement concrete mixes improve their mechanical strengths and fracture behavior remarkably but the thorough dispersion of MWCNTs in the matrix have to be insured.

Ultra Durable Concrete for Sustainable Construction

With the rapid consumption of natural resources, there is a growing concern about sustainable development. More than 6 billion tons of concrete are produced annually for various construction purposes with limited life expectancy. In addition, increasing cost of construction and demolition of concrete structures in densely populated areas is a great concern for the future. One of the best solutions to tackle these challenges is to increase the life expectancy of the structures. Residential structures and important civil structures are typically designed for a life span of 50 and 100 years respectively. However, the life expectancy of structures can be increased to several hundred years with careful planning and proper design. Cost of the concrete materials is not a considerable amount compared to the total cost for construction of reinforced concrete structures. Doubling the concrete materials cost may only increase the total construction cost by few percent but it can increase the life expectancy of structures significantly. In this work, a comparison between ultra durable concrete mixes with normal high strength concrete in terms of cost, mechanical and durability aspects is presented. Ultra durable concrete has superior qualities which makes it a favourable construction material for future structures.

Microstructure of different NaOH molarity of fly ash-based green polymeric cement

Every 1 ton of concrete leads to CO2 emissions which vary between 0.05 to 0.13 tons. About 95% of all CO2 emissions from a cubic yard of concrete are from cement manufacturing. It is important to reduce CO2 emissions through the greater use of substitute to ordinary Portland cement (OPC) such as fly ash, clay and others geo-based material. This paper, report on the study of the processing of geopolymer using fly ash and alkaline activator with geopolymerization process. The factors that influence the early age compressive strength such as molarity of sodium hydroxide (NaOH) have been studied. Sodium hydroxide and sodium silicate solution were used as an alkaline activator. The geopolymer paste samples were cured at 70°C for 1 day and keep in room temperature until the testing days. The compressive strength was done at 1, 2, 3 and 7 days. The result showed that the geopolymer paste with NaOH concentration of 12 M produced maximum compressive strength. Key words: Green polymeric concrete, fly ash, molarity, compressive strength.

Cement and concrete flow analysis in a rapidly expanding economy: Ireland as a case study

A national material flow model for concrete, the most popular construction material in Ireland, was developed based on the framework of material flow analysis. Using this model the Irish concrete cycle for the year 2007 was constructed by analysing the material life cycle of concrete which consists of the three phases of: production (including extraction of raw materials and manufacture of cement), usage (ready-mix and other products) and waste management (disposal or recovery). In this year, approximately 35 million metric tonnes of raw materials were consumed to produce 5 million metric tonnes of cement and 33 million metric tonnes of concrete. Concrete production was approximately 8 metric tonnes per capita. By comparison, the concrete waste produced in that year was minimal at only 0.3 million metric tonnes. Irish building stock is young and there was little demolition of structures in the year of study. However this build up of construction stock will have implications for the future waste flows when the majority of stock built in the last decade (43% of residential stock was constructed in the last 15 years) reaches its end of life.

The Boulder Dam and its Equipment

IN Engineering for January 1 is a well-illustrated introduction to a series of articles which will deal with the mechanical, hydraulic and electrical features of Boulder Dam. These articles will be written by Mr. P. A. Kinzie, Mr. J. A. Winter and Mr. L. N. McClellan, who have each been responsible for some part of the equipment for the control and utilization of the water impounded by the Boulder Dam, which is not inappropriately described as “the greatest engineering effort of its kind in history”. It was on December 21, 1928, that President Coolidge signed the Boulder Dam Act, which provided for the construction of a great dam on the Colorado River. The scheme had several objects. First, it was intended to prevent the serious floods which menaced the fertile district of the Imperial Valley; secondly, to conserve water for use in the same district during the hot dry summers; and thirdly, to provide a public water supply for the coastal cities of Southern California. The river has a length of approximately 1,700 miles, and drains an area slightly more than double the area of Great Britain. The site for the dam was chosen in Black Canyon about 300 miles upstream from the river mouth, a barren and inhospitable region, the character of which is well shown by the photographs in Engineering. The dam itself was completed in the summer of 1935. From the lowest portion of the foundation to roadway level it is 726 feet high; it is 660 feet thick at the base and 45 ft. thick at the crest, and contains about 6,600,000 tons of concrete. It is composed of massive vertical columns about 230 in number, interlocking both vertically and horizontally. Recently, the water impounded in the reservoir, Lake Mead, was estimated at ten billion gallons.