Concrete Technology

Fabric-cast concrete involves casting concrete in forms made with flexible formwork. This provides the potential to produce forms that are both structurally efficient and architecturally exciting in a relatively inexpensive and practical manner. By careful shaping of the fabric it is possible to produce complex shapes that would otherwise be difficult and expensive to produce using conventional formwork systems. This book contains six essays that describe the collaboration between the Universities of Edinburgh and East London, together with the Centre for Architectural and Structural Technology (CAST) at the University of Manitoba, in their detailed and practical research into concrete casting and formwork. Richly illustrated with photographs and diagrams and containing new and innovative research this book offers the architect, engineer and student inspiration and technical guidance in this re-emerging material. Published (publisher's copy) Peer Reviewed

Ultra High Strength Concrete (UHSC) merupakan terobosan yang sedang dikembangkan dalam beberapa dekade terakhir ini. UHSC memiliki beberapa kelebihan dibandingkan Normal Strength Concrete (NSC), yaitu beton UHSC memiliki ketahanan yang lebih baik terhadap asam, kebakaran, maupun ketahanan jangka panjang. Pada tahun 2010, di Indonesia telah dapat dibuat beton UHSC dengan kekuatan mencapai 140 MPa dengan memanfaatkan material lokal dengan ukuran yang sangat halus walaupun masih di laboratorium. Dalam penelitian ini akan dicari mix design yang dapat mencapai kuat tekan UHSC, pengaruh steam curing, penambahan steel fibres, dan proses vacuum dalam pembuatan UHSC. Pencarian mix design dilakukan terebih dahulu sebelum melakukan penelitian yang lain. Kuat tekan maksimum yang dicapai adalah sebesar 115 MPa pada umur 28 hari. Perlakuan steam curing memberikan pengaruh pada kuat tekan awal dan dengan melakukan proses vacuum dalam proses pemadatan benda uji tidak memberikan pengaruh dalam kekuatan. Penambahan steel fibres memberikan pengaruh yang baik dari segi ketahan dalam mengatasi keruntuhan yang getas. KATA KUNCI: ultra high strength concrete, UHSC, steam curing, steel fibres, vacuum. Ultra High Strength Concrete (UHSC) merupakan terobosan yang sedang dikembangkan dalam beberapa dekade terakhir ini. UHSC memiliki beberapa kelebihan dibandingkan Normal Strength Concrete (NSC), yaitu beton UHSC memiliki durability yang lebih baik terhadap asam, kebakaran, maupun ketahanan jangka panjang. Penentuan komposisi yang optimum dari setiap material penyusun beton UHSC sangat diperlukan, baik dari aggregat halus, semen, supplementary cement material, air, dan metode-metode yang akan digunakan selama proses pembuatan.

In this research, the use of clay bearing diatomites from Kütahya-Alayunt region in cement production as puzzolanic materials was investigated. Cements were produced by adding clay bearing dioatomites to the cement body by 5%, 10%, and 20% and grinding them together with clinker materials. After the tests, it was found that 10% and 20% clayed diatomite addition could be used in 42.5-class cement production. İf the strength of portland cement clinker was about 50 N/mm 2 . By utilizing this material, less clinker4 produced at 1450 o C will be needed which means lower emission rates causing environmental pollutions and a special type of cement can be obtained by using diatomite for lower specific gravity, heat and noise insulation

After several disastrous building collapses, concepts such as progressive collapse and robustness of structures have been reflected in many research papers and resulted in new codes and guidelines available in Europe and in the United States. The collapse of an entire structure or an essential part of it that is disproportionately large compared to the initiating local damage is considered a progressive collapse. In addition to the design guidelines, the mentioned standards provide provisions for the progressive collapse analysis of newly designed and existing structures. Therefor this study concerned with collapse behaviour of RCC building and various recent studies associated with it.

La apertura de la unidad de diálisis peritoneal se efectuó en abril de 2008. Con la fi nalidad de agilizar y estandarizar el procedimiento a seguir, se diseñó un plan estratégico de enfermería para la creación de nuestra unidad de diálisis peritoneal. Este trabajo pretende revelar la metodología utilizada para crear nuestra unidad de diálisis peritoneal y tras 3 años y medio de prestación de servicios, plasmar los resultados asistenciales obtenidos.

It is the objective of this project is to investigate the mechanical and chemical behaviour of new concrete type obtained by adding aluminium dross which is an impure aluminium mixture that results from metals melting and mixing with flux. The main advantage of this type of concrete over the conventional ones is the reduction in the quantity of raw materials. The results of this study indicate that aluminium dross can be used as an ingredient in the range of certain limits to improve expanded concrete/mortar and to improve the corrosion resistivity of concrete/mortar. The most interesting finding was that aluminium dross accelerates the setting time of concrete/mortar. Because of these findings it is suggested that aluminium slag added concrete/mortar may be used in the manufacturing of buildings subfloors, panels, blocks etc.

This study investigates the utilization of slag and fly ash (FA) as alternative cementitious binder. Combination of 60% slag and 40% FA was used as new binder. In addition, for activation of slag and FA, sodium hydroxide and calcium hydroxide was used as a chemical activator by 5% weight of the binder, separately. Water to binder and sand to binder ratios was kept 0.55 and 3 in mortar preparation, respectively. Superplasticizer was used by 2.5% of the weight of binder to get reasonable flow for casting. Physical and chemical properties of slag and FA, and fresh and hardened properties of mortar of the new binder were determined and compared with that of OPC. New binder which was activated by sodium hydroxide sets early than OPC. Mortar as produced from new binder with sodium hydroxide shows 12. 02, 18.15 and 26.20MPa compressive strength at 7, 14 and 28 days, respectively; while OPC mortar achieved 25.67, 30.08 and 35.78MPa compressive strength at the same ages and conditions. Sodium hydroxide exhibits greater activation performance than that of calcium hydroxide. Thus, depending on the preliminary test results it can be concluded that, with the presence of chemical activator, slag and FA can be used together as an alternative of OPC.

de contención de una central nuclear PWR-W tres lazos. El análisis debe ser totalmente tridimensional para permitir la consideración de los elementos estructurales más significativos, tener en cuenta el comportamiento no lineal de los materiales y estudiar la. sensibilidad de los resultados ante ciertas incertidumbres asociadas a algunos parámetros. El modelo computacional incluye las ecuaciones constitutivas para el hormigón y las armaduras de acero, la discretización espacial (elementos isoparamétricos con armado) y la resolución del problema estructural no lineal mediante algoritmos incrementales-iterativos con aceleradores de convergencia. Se describen los modelos estructurales utilizados y los análisis llevados a cabo para su calibración.

The paper investigates the prospects of corn-cob ash (CCA) as effective constituent in self-compacting concrete. The structural value of the composite was evaluated with consideration for its suitability as self-compacting concrete. Varied percentage of corn-cob ash at 0%, 10%, 20%, and 30% replaced cement in a mix of 1:2:4 concrete with variable plasticizer admixture of COMPLASTSP430 at 0%, 1%, 2% and 3% replacement. Specified tests for Self-compacting concrete (SCC), related to workability such as flowability, filling-ability, and passing-ability tests were carried out on fresh samples. Compressive strength of hardened cured (150 x 150 x 150) mm concrete cubes at 7days and 28 days were tested. The results showed that at 2% SP430 and 30% CCA replacement, the compressive strength was 20.37N/mm 2 , while the flowability, filling ability, passing ability, and segregation potential were 755mm, 29mm, 6 sec and 6.2mm respectively. On analysis and comparison of the results with known SCC standard, a percentage replacement of 2%SP430 and 30%CCA meet the requirement of self-compacting concrete.

The objective of this research is to investigate the influence of sugar s of different origins (Beet & Cane) on the setting times of cement pastes. Sugar is incorporated with three different types of cements under three different curing conditions (T emp. & R.Humidity). The test results revealed that, under normal curing conditions (T emp.=22 0 C & R.H.60%), the efficiency of sugar in retarding cement setting becomes higher with increasing sugar-content upto a certain limit. However, with further increase in sugar content, its retarding efficiency started to decrease, until at certain higher content it showed reverse effects (i.e, it accelerated the cement setting). Furthermore, sugar causes higher retardation when added a few minutes after the mixing of water and cement.

Fly ash is a side waste from the cement industry that can damage the environment. Fly ash has the potential as an essential material in making geopolymers. The study discusses how the relationship of the use of activator composition with the compressive strength of geopolymer mortar using fly ash. The sample uses activator sie NaOH and Na2SiO3. The sample uses several variations of NaOH composition and alkali modulus. NaOH variations consist of 13 M, 14 M, 15 M, and 16 M. Variations in alkali modulus include 1.5, 1.75, 2.00, 2.25, and 2.50. Treatment of samples according to room temperature and compressive strength testing was carried out at 7, 14, 28, and 56 days. Research has shown that the correlation between NaOH and alkali modulus on mortar strength is very significant. The highest compressive strength occurs at 14 M of all variations. The relationship of activator composition and compressive strength form 2nd polynomial equation order and NaOH optimum composition occurs betwee...

Self Compacting Concrete (SCC) is one solution to get concrete construction which it has good resistance. Durability of concrete was obtained by the good concrete compaction to be done by a skilled workforce. However, one of the negligence that often occur in the field ie after casting they was ignoring curing of the hardening concrete. This study discusses the workability of fresh concrete and mechanical properties (compressive strength and splitting tensile strength) on SCC without curing. Testing of the concrete workability based on EFNARC standard. The mechanical properties test based on ASTM standards. The method Compressive strength test based on ASTM standards 39 / C 39M - 12a, whereas splitting tensile strength accordance standard ASTM C496 / C496M-11. The results of the study indicate that the SCC without curing effect on the reduction in compressive strength at ages 1, 3, 7, 28, and 90 days in a row at 4.11 MPa (16.1%); 4.90 MPa (13.9%); 6.64 MPa (13.1%); and 6, 72 MPa (12...

El Hormigón Reforzado con Fibras (HRF) es un material de alta performance que se destaca por su capacidad de controlar la formación y propagación de fisuras y por su mayor tenacidad, lo que redunda en mejoras la vida en servicio de las construcciones. Si bien hace más de cuatro décadas que se conoce al HRF, en los últimos años se realizaron grandes avances en la materia que abren enormes perspectivas para su mayor aprovechamiento en la ingeniería, los cuales son puntualizados brevemente en este artículo.Fil: Zerbino, Raul Luis. Universidad Nacional de La Plata. Facultad de Ingeniería. Departamento de Construcciones; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentin

Este trabajo presenta los primeros resultados de una cooperación entre LEMITCIC y CNEA que tiene por objetivo analizar la influencia de la incorporación de diferentes tipos y contenidos de fibras sobre el proceso de corrosión de armaduras. Empleando un hormigón convencional y la misma matriz reforzada con fibras de acero se moldearon prismas de 90 mm de lado con una barra de 12 mm de diámetro embebida en el centro. Varios prismas fueron fisurados traccionando la barra de acero y otros permanecieron sin fisurar como referencia. Para inducir la corrosión se realizaron ciclos de inmersión y secado en una solución con una concentración de cloruros al 3% (m/m). Se evaluaron el potencial de corrosión, la densidad de corriente y la resistividad del hormigón. Se aprecia que la corrosión se activa rápidamente en presencia de fisuras y que las fibras no generan mayores efectos sobre el inicio de la degradación.

Concrete provides better compressive strength but low tensile strength.The addition of different nanomaterials and admixtures overcome this property.Graphene has been found the most promising material due to its large surface area and excellent properties of tensile strength.The main aim to adding up Graphene is to improve the material's strength, workability, and environmental sustainability. It is revealed that even a minute addition of 0.1% graphene leads to notable increases of up to 10-15% in compressive strength, 20-25% in tensile strenth, and 20-30% in flexural strength , respectively. Many studies have demonstrated that graphene and its derivatives, such as graphene oxide (GO), can effectively improve the mechanical characteristics of cementitious materials by increasing the hydration process of the cement and altering the pore distribution in the matrix. The addition of graphene offers also enhanced thermal properties and improve resistance to frost and corrosion.

In response to the growing need for sustainable construction and the growing preference for traditional materials, designers and developers are beginning to embrace alternative materials. One important factor in achieving this objective is the exploitation of agricultural leftovers and industrial waste materials. They also made an effort to assess the concrete's durability and efficacy in their trial. The Indian Standard offers a method for determining the proper blend for standard concrete. This method facilitated the development of a design incorporating sugarcane waste ash and rice waste ash rather than other materials.

Concrete is predominantly made up of cement. Cement manufacturing results in the emission of a large quantity of carbon dioxide in the air. Use of fly ash in concrete is advantageous for the environment and provides lasting durability. By utilizing a reduced amount of cement, it contributes to the conservation of materials such as limestone and coal that are essential for cement production. While it remains ever-present and never diminishes, generating it requires a considerable amount of power. So, it's a good idea to use cement carefully. Concrete is a durable substance can be moulded into various forms. It is frequently employed in construction for its multifunctionality. Finding a good replacement for cement in concrete is really important because we don't want to make the quality of the concrete worse. A powdery substance known as fly ash contains a significant quantity of cement. The study investigated the replacing other materials with fly ash on the M30 grade high strength concrete. We tested different quantities of cement, such as no cement, 10%, 20%, and 30%. Incorporating a larger amount of fly ash in the concrete mix creates a more manageable and robust material. Furthermore, it's been discovered that the inclusion of higher proportions of fly ash results in a reduction of concrete durability.

Have you ever dreamed of living in buildings that have a sense of serenity, yet are so alive they feel as if they live and breath in harmony with the land where they rest? Buildings that can actually help heal the land? Buildings that can channel water and help you grow your own food? Buildings that can surf through earthquakes, and repel fire? Buildings that appear to flow and undulate, rather than exist frozen as little boxes? Meet Doug Lacy, owner and founder of Flex Shell Architecture.

The objective of this study is to achieve an optimal formulation of self-compacting concrete using local materials from the country of Morocco, the use of this type of concrete remains very limited compared to a concrete vibrated in this country, due to lack mastery by companies. We will therefore try to study an optimal formulation that respects European standards and gives comparable results, even improved, to those of vibrated concrete, in order to be able to replace vibrated concrete with self-compacting concrete in construction sites. Thus, SCC mixtures containing amounts of fillers were examined, and with different Portland cement dosages: 350; 375 and 400 kg/m3. The method of formulation is made in accordance with French regulations. The results obtained were compared to these vibrated concrete counterparts containing the same cement dosages. Tests include compression, traction and flexion tests at 3, 7 and 28 days of age. Several studies have been carried out internationally...

The utilization of construction and demolition waste is useful for sustainable infrastructure development and protecting the environment. In this research, the properties of self-compacting concrete produced by replacing the natural coarse aggregates (NCA) with inferior recycled coarse aggregates (RCA) were investigated. The properties of self-compacting concrete (SCC) and self-compacting mortar (SCM) with varying replacements of RCA (0, 25, 50, and 100%) in NCA were determined. The flow, strength, early shrinkage tests, and microstructure using X-ray diffraction (XRD) and a scanning electron microscope (SEM) were investigated. The fresh property results indicated that the viscosity of freshly mixed SCC increased with higher replacement levels of RCA, thus reducing flow. The compressive strength of RCA SCC was reduced up to 30% for a 100% replacement level, while the flexural strength was reduced by about 15%. The compressive strength and flexural strength of SCMs, however, increase...

Concrete is an important material in construction. The main properties desired in concrete are that it should have high strength, low permeability and good workability etc. Due to urbanization, large area is being converted from bare land to concrete surface with the construction of buildings, roads, parking areas etc. Therefore, runoff occurs with greater peak flow causes flooding, choking of sewerage line. Due to which maintenance cost of infrastructure increases. So there is need to have concrete with more porosity having adequate strength so that lesser runoff is generated from areas paved with concrete. Pervious concrete is a concrete mixture comprised of cement, controlled amounts of water and uniformly graded coarse aggregate, little or no sand and sometimes other additives. Pervious concrete offers an attractive solution to the problem of excessive runoff. In this project Experimental investigation on tensile strength and compressive strength will be conducted to find out the maximum strength of pervious concrete by varying sizes of coarse aggregates and water cement ratio.

An experimental study was carried out to investigate the behaviour of steel fibre-reinforced high-strength concrete (HSC) short columns confined by square ties under monotonically increasing concentric compression. A total of 72 confined and 24 unconfined specimens were tested in this test programme. The test variables included aspect ratio and volume fraction of crimped steel fibres, volumetric ratio, yield strength and configuration of transverse tie reinforcement and concrete strength. The effects of these variables on the uniaxial behaviour of HSC short columns are presented and discussed. The results indicate that the addition of fibres to the HSC mix prevented the early spalling of the cover and increased the load-carrying capacity and ductility of the specimens over that of comparable non-fibre columns. The effect of mixed aspect ratio of fibres on the stress–strain behaviour of confined HSC was also studied by blending the short and long fibres. It is shown that a higher gai...

This study investigates the effects of seawater on the compressive strength of concrete through experimental analysis. Experimental cement concrete cubes of 150mm x 150mm x 150mm were cast using different mixes of concrete mixed and cured in seawater in order to determine the compressive strength. All the mixes were prepared using various water cement ratios (w/c) ranging from 0.5 to 0.6 by weight. A total of 60 concrete cubes were made in twenty batches; the cubes were cast and cured in sea water. The curing was done for 21days, and then crushed using the Compressive Strength Test Apparatus at the prescribed age. The study shows an increase in the compressive strength of concrete for concrete specimens mixed with seawater during the early stages of curing, up to 14 days. However, after 28 days and beyond, the compressive strength of concrete mixed and cured with seawater begins to decrease.

This paper presents a summary of our investigations that were aimed to assess the influence of various physical and mechanical parameters on the performance of reinforced concrete (RC) beams strengthened with fiber reinforced plastic (FRP) plates. The work was divided into two phases. The first phase investigated the influence of FRP plate length, fiber orientation, and surface preparation on the performance of FRP-reinforced RC beams. The FRP in this phase of the work was E-glass/epoxy. The second phase of the study was designed to confirm the validity of our hypothesis, which postulated that the delamination of the FRP plate would be a function of the Poisson ratio mismatch between concrete and FRP plate. Results from the second phase also suggested that less expensive glass FRP plates could adequately replace the more expensive carbon FRP plates by offering the beam more ductility, without sacrificing its expected performance. Moreover, results from both phases showed that the lateral stiffness of the FRP plate contributed to the overall flexural stiffness of the strengthened beam.

Fabric-cast concrete involves casting concrete in forms made with flexible formwork. This provides the potential to produce forms that are both structurally efficient and architecturally exciting in a relatively inexpensive and practical manner. By careful shaping of the fabric it is possible to produce complex shapes that would otherwise be difficult and expensive to produce using conventional formwork systems. This book contains six essays that describe the collaboration between the Universities of Edinburgh and East London, together with the Centre for Architectural and Structural Technology (CAST) at the University of Manitoba, in their detailed and practical research into concrete casting and formwork. Richly illustrated with photographs and diagrams and containing new and innovative research this book offers the architect, engineer and student inspiration and technical guidance in this re-emerging material

Specification of materials for concrete repair is a complex task requiring broad knowledge of materials science, engineering and construction practice. In this paper, several issues important for proper design and implementation of concrete repair are discussed. It is stressed that the specification documentation is not a formality, but rather a critically important engineering step in view of fulfilling the durability and service life requirements.

 Abstract: Geopolymer concrete utilizes an alternate material including Red Mud and Rice Husk Ash as binding material in place of cement. This Red mud and Rice husk ash reacts with alkaline solution Sodium Hydroxide ( NaOH) and Sodium Silicate (Na2SiO3) to form a gel which binds the fine and coarse aggregates. In this experimental carry on replacement of cement with red mud and rice husk ash in various percentages like ( 10% &90%,20% &80%,30%&70% ) An attempt has been made to find out an optimum mix for the Geopolymer mortar. To determine the compressive strength of geopolymer mortar at 28days. This paper has focused on a study on geopolymer ferrocement flat panel in sunlight curing to eliminate oven curing .

Jalan dari beton atau aspal memiliki sifat yang kedap air, sehingga di jalan-jalan tersebut air akan menggenang. Seiring dengan bertambahnya kemajuan teknologi, manusia terdorong untuk mengembangkan kreativitas dan salah satunya adalah perkembangan konstruksi jalan dengan menggunakan paving stone/paving block. Pada penelitian ini akan dibuat paving stone berpori dengan penambahan bahan abu terbang limbah batu bara dengan komposisi 10-50% dari berat semen untuk mengetahui nilai permeabilitas serta nilai kuat tekan. Pembuatan benda uji akan menggunakan cetakan paving dengan ukuran 21x10.5x8 cm, dimana tiap komposisi paving stone berpori akan dibuat 12 buah benda uji. Pengujian kuat tekan paving stone berpori dilakukan pada umur 7, 14 dan 28 hari, sedangkan untuk pengujian permeabilitas dilakukan pada umur 28 hari. Berdasarkan hasil penelitian, penambahan abu terbang limbah batu bara (fly ash) akan mempengaruhi nilai dari kuat tekan benda uji, nilai permeabilitas dan nilai porositas. h...

The Principle objective of this project is to analyze and design the high rise building G+14 .The analysis is done by the use of software Staad pro v8i. The method use in this work is linear static analysis method. In present scenario buildings with floating column is a typical feature in the modern multistory construction in urban India. Such features are highly undesirable in building built in seismically active areas. This study highlights the importance of explicitly recognizing the presence of the floating column in the analysis of building. The behavior of a building during earthquakes depends critically on its overall shape, size and geometry, in addition to how the earthquake forces are carried to the ground. The earthquake forces developed at different floor levels in a building need to be brought down along the height to the ground by the shortest path.

Self compacting concrete (SCC) is a relatively new material in building industry, which doesn’t require mechanical compaction. The material’s high fluidity allows the flow under its own weigh through the narrow sections, around the reinforcement, filling completely the formwork without segregation. The capacity to spread of SCC is attained by increased powder content and limited coarse aggregates volume. The most commonly mineral addition is filler limestone, an industrial by product. The properties of fresh SCC were thoroughly studied, but the investigations of the characteristics of hardened SCC remains inconsistent. The changes made to the concrete composition modifies mechanicals characteristics. In this study is investigated the influence of limestone powder content on the compressive strength and modulus of elasticity.

Oil palm shells (OPS) has been used as an aggregate in concrete mixture, replacing the normal sense aggregate in many countries, since long time, and it is still an important aggregate in terms of quantity used. In Malaysia, the development of using oil palm shell as lightweight aggregate in construction industry, especially in structural application started about 30 years ago. Today; concrete is one of the most versatile construction materials. Many researchers found that OPS light weight concrete performances need to be enhanced especially when used for structural applications. In this research work an efforts were taken place to enhance OPS concrete performances by using bamboo fibers. Compressive strength, impact energy absorption and crack resistance were investigated for different mix design of bamboo fiber content and good results were gained. The compressive strength decreased marginally the percentage of bamboo fiber of 2% by cement weight. The impact energy absorption for 1% bamboo fiber increase about 1.9 times for service (first) crack and 1.5 times for the ultimate (failure) crack as compared to the service (first) crack and ultimate (failure) crack of the control sample with no bamboo fiber respectively. However, the impact energy absorption for 2% bamboo fiber increase considerably about 2.3 times for service (first) crack) and 1.8 times for the ultimate (failure) crack as compared to the service (first) crack and ultimate (failure) crack of the control sample with no bamboo fiber respectively. As such the 2% percentage of bamboo fiber has better performance than 1% percentage of bamboo fiber in term of impact energy absorption and crack resistance especially under service (first) crack condition. The difference in bamboo fiber length has only marginal effect on the impact energy absorption or surface crack resistance for service (first) crack and ultimate crack condition. The results show that oil palm shell light-weight concrete with bamboo fibers indicate a potential future of this material to be used as an impact resistance composite structures.

Green technology and sustainable development are the main concern in any country around the world; researchers and engineers are urged to provide the best solution to maintain the environment for the future generation. Malaysia is the world largest oil palm exporter, producing over 4 million tons of oil palm shells as main solid waste of the industry annually, which causing an environmental problem. An optimum mix design should be acquired through various trial mixes to ensure the re-use of oil palm shells lightweight concrete to achieve the required structural performance. A self-fabricated drop-weight impact test rig, have been used in this research work, to simulate a low-velocity projectile impact on the slab specimens. Three parameters are tested for specimens with or without geogrid reinforcement; where the first parameter is the effect of OPS content on impact resistance, and it is found out that the increment of OPS content will reduce the impact resistance of concrete. For the second parameter, the effect of geogrid layers on impact resistance is evaluated; as the increment of geogrid layer does improve the impact resistance, but the effect is more obvious for ultimate crack resistance than the first crack resistance. The last parameter is the contribution of geogrid type on impact resistance; comparison are made between geogrid 60/60 and geogrid 80/80, result show that geogrid 80/80 has the overall better performance.

Concrete is an important material in construction. The main properties desired in concrete are that it should have high strength, low permeability and good workability etc. Due to urbanization, large area is being converted from bare land to concrete surface with the construction of buildings, roads, parking areas etc. Therefore, runoff occurs with greater peak flow causes flooding, choking of sewerage line. Due to which maintenance cost of infrastructure increases. So there is need to have concrete with more porosity having adequate strength so that lesser runoff is generated from areas paved with concrete. Pervious concrete is a concrete mixture comprised of cement, controlled amounts of water and uniformly graded coarse aggregate, little or no sand and sometimes other additives. Pervious concrete offers an attractive solution to the problem of excessive runoff. In this project Experimental investigation on tensile strength and compressive strength will be conducted to find out the maximum strength of pervious concrete by varying sizes of coarse aggregates and water cement ratio.

Resumo O diagnóstico de estruturas em utilização é um desafio, pois envolve logística de recursos financeiros e de tempo, além de interferir em sua utilização e na dinâmica de seus usuários. O ensaio de reconstituição de traços é uma alternativa interessante para se definir propriedades de matrizes cimentícias, visto que traz resultados importantes sobre o material, como o teor de cimento e a resistência. Este estudo visa avaliar os resultados obtidos com base em um estudo de caso utilizando o ensaio de reconstituição de traços em detrimento dos procedimentos de FRX ou Resistência Mecânica, realizados em amostras diferentes. Observou-se uma proximidade entre os resultados obtidos para propriedades das amostras analisadas, o que indica possibilidade de utilização do ensaio de reconstituição em paralelo com ensaio de resistência à compressão para uma análise mais confiável e efetiva.

A microorganisms-based bioplasticizer (MEF) is presented as plasticizing admixture. MEF increases flowability of pastes and mortars at relatively high dosages. The presence of lactic acid at MEF seems to influence plasticizing properties. At high dosages MEF seems to influence cement hydration, and has a retarding effect. Rheology tests in pastes and mortar prove changes of plasticity and viscosity.

Wastewater coming from slaughterhouses by-products contains high amounts of nitrogen, phosphorus, organic matter, salts, and so on. The effluent comes from the water used to wash the animals, scalding, washing the floor and the machines, cleaning of equipment, etc. Before discharging the effluent in the water body, the effluent needs to be treated. To remove the large amount of organic matter and nutrients this study proposed the use of a combined system composed by three biological reactors: anaerobic, aerobic and anoxic. The best removal efficiencies were 90% for COD and 50% for NH 4 +-N, what decreases large pollutant potential.

Wastewater coming from slaughterhouses by-products contains high amounts of nitrogen, phosphorus, organic matter, salts, and so on. The effluent comes from the water used to wash the animals, scalding, washing the floor and the machines, cleaning of equipment, etc. Before discharging the effluent in the water body, the effluent needs to be treated. To remove the large amount of organic matter and nutrients this study proposed the use of a combined system composed by three biological reactors: anaerobic, aerobic and anoxic. The best removal efficiencies were 90% for COD and 50% for NH 4 +-N, what decreases large pollutant potential.

A comprehensive and rational design of a concrete mix is extremely complex as it is controlled by numerous factors which depend upon the properties and source of the materials, besides the methods of preparation, compaction, placement and curing of concrete and the requirements of the construction job. When these factors are incorporated in the design of a concrete mix, the task of selecting proportions of ingredients becomes difficult and in most cases inaccuracies in the required properties of concrete result, which are corrected by trial and error procedures.

With advancing technologies in the construction industry, it is a very much correct time to address for advancement in the materials also. Many newer materials as an alternative to conventional practices are introduced, and many of it is also accepted for usage. Different constituents having different properties, however, when composed together the resultant is an entirely unique one as concrete. Since around the period of 1900, the cement was invented, and later the use of concrete became widespread. After about a century, among various uses of concrete, a concept of self-compacting concrete is emerging since past a few years. The nations of Japan and USA has standardised the practice of SCC whereas India is yet lacking behind for the publication of a standard for manufacturing and practising with it. Current research work is an attempt to check for application of the SCC as an alternative concrete in the structural rehabilitation work. Mix design for M55 Grade was carried out afte...

With the proliferation of the population and the evolution of lifestyles, the issue of plastic waste has emerged as a significant environmental challenge due to its non-biodegradable nature and voluminous generation. However, there has been a scarcity of substantial research efforts to examine the influence of plastic waste on the properties of concrete. The current study aims to undertake a comprehensive review of the findings from previous research endeavors, with a specific focus on the period between 2020 and 2024, to investigate the potential of utilizing plastic waste as an aggregate in cement concrete components. To present a comprehensive review of this study, the literature pertaining to the use of plastic waste as aggregates in cement concrete has been examined and analyzed. The key types of plastic waste and their recycling as aggregates in concrete mixtures are briefly discussed. The physical and mechanical properties of these plastics and their impact on the mechanical and durability properties of concrete were evaluated, as well as their economic benefits and the limitations to their usage. The results indicate that the addition of specific categories of plastic waste enhances the workability and reduces the density, compressive, flexural, and tensile strengths of concrete to acceptable levels compared to the control samples. The incorporation of plastic waste into the cement concrete matrix leads to significant economic benefits by reducing the consumption of raw materials and the emission of CO 2 into the atmosphere. The addition of plastic waste as an aggregate in concrete mixtures can also decrease the thermal conductivity property of concrete. Furthermore, the durability properties can be improved with the incorporation of a small quantity of plastic waste. Additionally, the use of plastic waste as an aggregate in concrete mixtures has the potential to reduce production costs and alleviate environmental pollution for a cleaner environment. Therefore, this investigation concludes that the appropriate utilization of plastic waste in construction projects can greatly enhance sustainability and mitigate the adverse impact of plastic waste on the environment.

Currently civil engineering construction particularly concrete structures in the area of building and water resources especially in developing regions where much concrete is used. Compressive strength of concrete is usually expected to meet commonly specified concrete quality K-250 for buildings and K-300 for district roads. This research aims at determining the characteristics of nickel slag as substitute of coarse aggregate and design characteric compressive strength K-300 whether achievable or not. Then, concrete mix design was carried out to determine composition of concrete materials and make  15-30 cm cylindrical concrete sample for characteristic compressive strength. The results showed characteristics of nickel slag as a good substitute of coarse aggregate for concrete materials. Characteristic compressive strength of concrete was 330,14 kg/cm² ˃ specified concrete quality K-300 (300 kg/cm²), while flexural strength 4,22 N/mm² (42,2 kg/cm²), 12,78 % of characteristic compre...

Recent work demonstrated that 50:50 sand-recycled polycarbonate (rPC) composites have an average compressive strength of 71 MPa, which dramatically exceeds the average offered by commercial concrete (23.3-30.2 MPa). Due to the promising technical viability of replacing carbon-intensive concrete with recycled sand plastic composites, this study analyzes the cradle-to-gate environmental impacts with a life cycle assessment (LCA). Sand-to-plastic composites (50:50) in different sample sizes were fabricated and the electricity consumption monitored. Cumulative energy demand and IPCC global warming potential 100a were evaluated to quantify energy consumption and greenhouse gas emission associated with sand-plastic brick and two types of concrete, spanning the life cycle from raw material extraction to use phase. The results showed that at small sizes using Ontario grid electricity, the composites were more carbon-intensive than concrete, but as samples increased to standard brick-scale rPC composite bricks, they demonstrated significantly lower environmental impact, emitting 96% less CO2/cm 3 than sand-virgin PC (vPC) composite, 45% less than ordinary concrete, and 54% less than frost-resistant concrete. Energy sourcing has a significant influence on emissions. Sand-rPC composite achieves a 67-98% lower carbon footprint compared to sand-vPC composite and a 3-98% reduction compared to both types of concrete. Recycling global polycarbonate production for use in sand-rPC composites, though small compared to the total market, could annually displace approximately 26 Mt of concrete, saving 4.5-5.4 Mt of CO2 emissions. The results showed that the twin problems of carbon emissions from concrete and poor plastic recycling could be partially solved with sand-rPC building material composites to replace concrete.

Recent work demonstrated that 50:50 sand-recycled polycarbonate (rPC) composites have an average compressive strength of 71 MPa, which dramatically exceeds the average offered by commercial concrete (23.3-30.2 MPa). Due to the promising technical viability of replacing carbon-intensive concrete with recycled sand plastic composites, this study analyzes the cradle-to-gate environmental impacts with a life cycle assessment (LCA). Sand-to-plastic composites (50:50) in different sample sizes were fabricated and the electricity consumption monitored. Cumulative energy demand and IPCC global warming potential 100a were evaluated to quantify energy consumption and greenhouse gas emission associated with sand-plastic brick and two types of concrete, spanning the life cycle from raw material extraction to use phase. The results showed that at small sizes using Ontario grid electricity, the composites were more carbon-intensive than concrete, but as samples increased to standard brick-scale rPC composite bricks, they demonstrated significantly lower environmental impact, emitting 96% less CO2/cm 3 than sand-virgin PC (vPC) composite, 45% less than ordinary concrete, and 54% less than frost-resistant concrete. Energy sourcing has a significant influence on emissions. Sand-rPC composite achieves a 67-98% lower carbon footprint compared to sand-vPC composite and a 3-98% reduction compared to both types of concrete. Recycling global polycarbonate production for use in sand-rPC composites, though small compared to the total market, could annually displace approximately 26 Mt of concrete, saving 4.5-5.4 Mt of CO2 emissions. The results showed that the twin problems of carbon emissions from concrete and poor plastic recycling could be partially solved with sand-rPC building material composites to replace concrete.

The main constituents of the construction industry usually involve building materials which include cement, bricks, steel, fine and coarse aggregates. The majority of concrete production worldwide incorporates sand as a fine aggregate. Since, all of these materials are obtained from finite natural resources, their ongoing depletion will have a negative impact on the environment. In order to minimize environmental harm and preserve natural resources, this study focuses on the recycling of waste materials through the use of waste marble powder (WMP) as a substitute for fine aggregate (sand) in concrete. The sawing and cutting waste generated by the marble industry is substantial and has a negative impact on the environment. Our research concluded that by replacing sand with waste marble powder, mechanical and durability properties of concrete are enhanced thus, making it more resilient and sustainable. WMP was incorporated to concrete in different amounts. For this investigation sand was replaced in four proportions (10%, 20%, 30%, 40% by weight). The grade of concrete is M30, water-to-cement ratio was maintained at 0.45 and 0.28% superplasticizer was added to cement by weight to increase the workability. The experiments employed both destructive testing (DT) and non-destructive testing (NDT). Following a 28-day curing period, at a 40% replacement ratio, the results of the tests for compressive strength, split tensile strength and flexural strength demonstrated improvements of 17.5%, 27% and 35%, respectively. The maximum value of the rebound hammer test exhibited an increment of 15%; the ultrasonic pulse velocity (UPV) indicated an improvement of 3% and the rate of water absorption declined to 45%, 40% and 36% for cubes, cylinders and beams respectively.