Curing of concrete nptel pdf

Cement is the most used material in any construction. The performance of the sulphur infiltrated concrete generally has been found satisfactory against freezing and thawing, sea water attack, wetting and drying conditions. These include rapid curing at ambient temperatures from. Concrete introduction concrete is a composite with properties that change with time. Concrete is a composite material composed of fine and coarse aggregate bonded together with. Bhattacharjee,department of civil engineering,iit delhi.

This subcourse reflects current doctrine when this subcourse was prepared. Curing should begin immediately after the finishing operation. Prestressed concrete structures nptel online videos. The time period in which a specified strength should be achieved may range from a few 300 design and control of concrete mixtures eb001 table 171.

Mike day everything about concrete recommended for you. Concrete curing methods curing of concrete what is curing. Curing can be described as keeping the concrete moist and warm enough so that the hydration of cement can continue. A concrete building, bridges and other structures include members such as columns, walls, beams, slabs, footings, piers, retaining walls, conduits and tunnel linings. Nptel provides elearning through online web and video courses various streams.

Ready mix concrete seminar report, ppt, pdf for civil. Concrete mix design definition concrete mix design is defined as the appropriate selection and proportioning of constituents to produce a concrete with predefined characteristics in the fresh and hardened states. Keep the concrete immersed in water during the curing period to fulfill the moisture requirements of concrete. When the concrete has hardened then for the vertical faces formwork ties may be. In general, concrete mixes are designed in order to achieve a defined workability, strength and durability. Nptel syllabus concrete engineering and technology video course course outline the course deals with different aspects of modern concrete technology that has evolved as a result of rapid developments in mechanized construction, use of mineral and chemical admixtures in concrete. These structural members are cured by one or more methods described in concrete curing methods. Vertical shaft kilns were replaced with rotary kilns and ball mills were used for grinding cement. The curing compound shall not allow the concrete specimen to lose more than.

The goal of the calibration is to determine a relationship between maturity and strength for a specific mix. The course on concrete technology focuses on concrete making materials including supplementary cementitious materials. Curing has long been recognized as an important process in constructing durable concrete pavements. Minimal delay is especially important in hot andor dry weather to avoid rapid evaporation from the concrete surface. Concrete basicsaddresses the needs of unskilled and semiskilled persons undertaking general concreting projects including home and handyman projects. The use of permeable concrete for ground water recharge pdf. Civil engineering building materials and construction nptel. It is represented by an index value that can be measured in real time in the field. Oct 05, 2012 curing of concrete curing may be defined as the operation of maintaining humidity and temperature of freshly placed concrete during some definite period following placing,casting or finishing to assure satisfactory hydration of cement and proper hardening of the concrete if the curing is neglacted in early period of hydration, the quality of.

Blended cements like fly ash cement have slower rate of strength. Typically, wires or tendons are stretched and then blocked at the ends creating compressive stresses throughout the members entire crosssection. Curing is the maintaining of an adequate moisture content and temperature in concrete at early ages so that it can develop properties the mixture was designed to achieve. Highearlystrength concrete, also called fasttrack concrete, achieves its specified strength at an earlier age than normal concrete. Reactive powder concrete rpc is an emerging technology that lends a new dimension to the term high performance concrete. Curing is the maintenance of a satisfactory moisture content and temperature in concrete for a period of time immediately following placing and finishing so that the desired properties may develop fig. It is hoped that the material will also be useful to teachers and practitioners. During service, the quality of concrete provided by initial curing can be improved by subsequent wetting as in the cases of foundations or water retaining structures.

Maturity is the relationship between concrete temperature, time, and strength gain. In your own work, always refer to the latest publications. To design composite construction ofprestressedstructural elements. We can also use 200mm cube, but you have to convert the compressive strength of 200mm cube to the equivalent of 150mm cube to know the actual strength of the concrete. Curing of concrete curing may be defined as the operation of maintaining humidity and temperature of freshly placed concrete during some definite period following placing,casting or finishing to assure satisfactory hydration of cement and proper hardening of the concrete if the curing is neglacted in early period of hydration, the quality of. To examine the transmission of prestress and design the anchorage reinforcement using the codified procedures. This method of curing is termed as membrane curing. Cold concrete can delay curing and stripping time and affect productivity.

It has immense potential in construction due to its superior mechanical and durability properties compared to conventional high performance concrete, and could even replace steel in some applications. The durable concrete should have low permeability with adequate cement content, sufficient low free watercement ratio and ensured complete compaction of concrete by adequate curing. Lecture 24 prestressed concrete prestressed concrete refers to concrete that has applied stresses induced into the member. Additional information on workability and quality of concrete can be obtained by observing the manner in which concrete slumps. Mixture adjustments at the jobsite for air entrainment, and the addition of other admixtures, is permitted, followed by sufficient mixing. Concrete is cured to complete the hydration process, and to gain strength of concrete.

Fundamental of concrete constituents, proportioning, mixing, transportation, placing and curing. We can also use 200mm cube, but you have to convert the compressive strength of 200mm cube to the equivalent of 150mm cube to. The method of curing described above come under the category of moist curing. Polymer concrete is a composite material in which the aggregate is bound together in a matrix with a polymer binder. Properly curing concrete leads to increased strength and lower permeability and avoids cracking where the surface dries out prematurely. This omission often results in a soft surface skin, which will easily dust under foot traffic. The white pigmented compound shall exhibit a reflectance of at least 60% of that of a standard magnesium oxide reference plate. Foam concrete pumps easily with relatively low pressures via hose over long distances. Types of curing compounds type 1 clear of translucent without dye. Inadequate curing can result in surface damage in the form of plastic shrinkage cracking, spalling, and erosion of paste. Nptel syllabus concrete engineering and technology. Degree of hydration increases with increase in the time of curing. Use of concrete in more challenging environments, better. Concrete basicsaims to provide a clear, concise explanation of all aspects of making quality concrete.

The course on concrete technology focuses on concrete making materials including. It can also be done by covering with special type of water proof paper so. When placing in excavations, foam concrete conforms to every sub grade contour. Curing maintenance of a satisfactory moisture content. Allowing the concrete surface to freeze will weaken the surface and. The following is a list of specifications which may be related to this section. Mixwater and aggregate temperatures, boiler energy, curing equipment energy and building heat may all be adjusted to achieve the optimum curing temperatures. Concrete technology notes pdf ct notes pdf eduhub sw. Pdf effect of curing methods on density and compressive. Inadequate protection of freshly placed concrete from rain, snow or drying winds. Concrete maturity indicates how far curing has progressed. Temperature tests are useful, not only in determining concrete performance, but for creating possible cost savings. However, concrete can also deteriorate with time due to physical and chemical attacks. The benefits of curing concrete are significant, as can be the.

Contractor shall furnish all labor, tools, and equipment for curing plain, reinforced, and posttensioned, and castinplace concrete. Also explore the seminar topics paper on ready mix concrete with abstract or synopsis, documentation on advantages and disadvantages, base paper presentation slides for ieee final year civil engineering ce or ieee civil construction btech, be, mtech students for the year 2017 2018. It may be defined as the operation of keeping a freshly placed concrete moist during a specified period after its finishing to ensure complete hydration of cement particles or other cementing material for obtaining a properly hardened concrete. Mix play all mix nptelhrd youtube how to form, pour, and stamp a concrete patio slab duration. A guide to concrete strength giatec scientific inc. Building construction notes pdf linkedin slideshare.

Tests on concrete workability tests slump cone test, compaction factor test. A durable concrete performs satisfactorily in the working environment during its anticipated exposure conditions during service. Proper curing allows the concrete to develop its potential strength and durability. Batching, mixing, transporting, and handling concrete. Highdensity custom radiation protection, shielding and storage concrete marshields interlocking high density concrete block is an excellent choice where space is limited. Effect of curing methods on density and compressive. Curing is defined as maintenance of a satisfactory moisture content and temperature in the concrete for a period of time immediately following placing and finishing so that the desired properties may develop. Curing begins immediately after placement and finishing so.

It is against this background that this study seeks to assess the effect of different curing methods on the density and compressive strength of concrete and to determine methods that isare unsuitable which may impair the quality of the concrete. High density concrete gives a composite shield for both neutron and gamma radiation. Quality of concrete can also be further assessed by giving a few tappings or blows by tamping rod to the base plate. Highdensity custom radiation protection, shielding and. It acts as a binder which binds aggregate and sand together in concrete. The need for adequate curing of concrete cannot be overemphasized. Page of 7 curing of ncreteco n curing by preventing excessive loss of moisture from the concrete. We can provide high density concrete blocks up to 300 pounds per cubic foot. Lab manual of concrete technology sanjay ghodawat group of. The maturity index value considers concrete temperature and curing time. Prevent the loss of the mixing water from concrete by sealing its surface. In other words, maturity is a value that represents the progression of concrete curing. In reinforcement detailed drawings and bar bending schedules, you usually come across the following terms concrete cover, clear cover, nominal cover and effective cover today i will answer.

The composites do not contain a hydrated cement phase, although portland cement can be used as an aggregate or filler. The deformation shows the characteristics of concrete with respect to tendency for segregation. Mar 11, 2014 mix play all mix nptelhrd youtube how to form, pour, and stamp a concrete patio slab duration. More elaborately, it can be described as the process of maintaining a satisfactory moisture content and a favorable temperature in concrete during the period immediately following placement, so that hydration of cement may continue until.

Explore ready mix concrete with free download of seminar report and ppt in pdf and doc format. Selfcuring concrete is one of the special concretes in mitigating insufficient curing due to human negligence paucity of water in arid areas, inaccessibility of structures in difficult terrains. Hydration, porosity and strength of cementitious materials. This scc is usually an designed product comprising bare cement, aggregates, h2o and. Concrete paste fagg concrete agg fagg paste fpaste v v v 1 h h h h 0 20 40 60 80 100 aggregate volume % 0 20 40 60 80 100 s h r i n k a g e % o f p a s t e typical concrete stiffer aggregate more effective in restraining paste shrinkage n 1. Going through the course one would develop firsthand knowledge on concrete production process and properties and uses of concrete as a modern material of. Highperformance concrete hpc exceeds the properties and constructability of normal. Methods of curing concrete curing types and techniques. Concrete production process also forms a part of the discussion. Inspect all materials used in the construction of concrete. Curing is the process of controlling the rate of moisture loss from concrete to ensure an uninterrupted hydration of portland cement after concrete has been placed. Form work short questions with answers 8 multiple choice questions mcq 8 answers to multiple choice questions 8 exercise 8 references chapter 9 strength of concrete 91. Polymer concrete composites possess a unique combination of properties dependent on the formulation.

The increase of strength with its age during curing is considered to be marginal after 28 days. Curing has a strong influence on the properties of hardened concrete. It is more durable than conventional concrete in high concentrations of h 2 so 4 and hcl. As a result, mix calibration is required to implement this concept in a project. Degree of hydration of cement system is unaffected by the presence of. To analyze and design prestressed concrete flexural members using codal provisions. Mixwater and aggregate temperatures, boiler energy, curingequipment energy and building heat may all be adjusted to achieve the optimum curing temperatures. To give exposure to prestressed concrete in special structures. This study considered the effect of different methods of curing on density and compressive strength of concrete. Mixture adjustments at the jobsite for air entrainment, and the addition of other. Foam concrete forms a rigid, wellbonded body after hydrating. Another method of curing is to cover the wetted concrete surface by a layer of water proof material, which is kept in contact with the concrete surface of seven days.