Pdf factors affecting the quality of concrete containing. Traditionally, durability has been addressed in asphalt mixture design and construction through a combination of the following. Test methods like astm 1202, standard test method for electrical indication of concretes ability to resist chloride ion penetration monitor the amount of electrical charge passed through cylindrical specimens for six hours. Factors affecting durability of concrete aggregate. Raveling and surface initiated cracking are the primary distresses associated with durability issues. As the professional manufacturer of concrete mixers and concrete batching plants, we will tell you some factors that affect the quality of concrete. Durability of concrete factors affecting durability of. A solid material helps the earth by saving assets and decreasing squanders and the. This is a global problem that annually costs public and private sectors worldwide billions of dollars. Factors affecting the durability of concrete and the benefits. Strength and durability properties of cement mortar and concrete depends upon envionmental condition if cement species are in sea water than ions of salt may replace the calcium or silicate ion. Following are the factors that affect the durability of concrete.
Concrete surfaces sheltered from severe rain or freezing whilst wet. Concrete is very weak in tension, it is so weak that the tensile strength of concrete is usually ignored in the design of. This is the main dimension of the material which a design engineer is concerned of. Water should be free and clean from oils, acids, alkalies, sugar, salts organic materials etc. The strength of concrete is affected by various factors including its ingredients, environmental factors, postprocesses or works, and so on. Factors affecting workability of concrete a concrete is said to be workable if it is easily transported, placed, compacted and finished without any segregation. Moisture present in the atmosphere will also affects durability of concrete structures. To investigate the durability of concrete, this study examined fine aggregate composed of different. What are properties of hardened concretegoverning factors. Commercial and residential concrete project costs are influenced by different factors, a few of which are common for both. The concrete durability has been defined by american concrete institute aci as its resistance to the weathering activities, different chemical attack, scratch and other dilapidation processes and activities. Following are the factors affecting durability of concrete.
The ability of concrete to withstand the conditions for which it is designed without deterioration for a long period of years is known as durability. Durability and permeability of concrete 605 unit5 2. Jan 05, 2015 durability and permeability of concrete 1. Accordingly cement alone is not a building material, it is the concrete which is a. Effectiveness of a densification process to create strong and durable bonding in densified products such as pellets, briquettes, and cubes can be determined by testing the strength i. Concrete surfaces with poor durability have been a problem on some highways in.
Concrete is very weak in tension, it is so weak that the tensile strength of concrete is usually ignored in the design of reinforced concrete structures. Table 3 specification for marine concrete in port works design manual 4. The durability of contemporary concrete is discussed in view of changed technology and performance requirements. Ip this investigation examined variables influencing the 28day com pressive strength and socycle salt scaling loss of concretes made with 18 type 10 cements. Physical and chemical characteristics affecting the durability of concrete article pdf available in aci materials journal 882. The relative quantities of cement, aggregates and water mixed together, control the properties of concrete in wet state as well as in hardened state. Concrete durability testing kryton international inc. Carbonation begins at the concrete surface and slowly penetrates deeper, typically at a rate of about. The importance of the factors affecting concrete shrinkage 1 purpose this paper summarises the research on the causes creating shrinkage strains in concrete and thus the likelihood of shrinkage cracking, illustrates the conflicting requirements in the selection of concrete properties and attributes and provides information on the relevance. Permeability of concrete factors affecting permeability.
If cement is reduced, then at fixed wc ratio the workability will be reduced leading to inadequate compaction. With low wc ratio the permeability decreases to such a level that these concretes are impervious to water. There are many factors that can affect the strength of concrete. It is a timedependent deformation which reduces the volume of concrete without. Factors affecting the choice of mix proportions compressive strength workability durability,durability decreases with increase in wc ratio higher is the aggressiveness of the environment lower should be the wc ratio strength of paste increases with cement content and decreases with air and water content studies show that, c. Test results show that slump, curing, and time of finishing are the most important factors affecting the abrasion resis tance of concrete surfaces. Durability of concrete depends upon the following factors. In all chemical and physical processes influencing durability of concrete structures, two factors are dominant. Kaushal kishore, materials engineer, roorkee concrete strength cement like water, aggregates and some times admixtures is one of the ingredient of concrete. This paper discusses the suitability of producing concrete with 100 % recycled aggregate to meet durability and.
The rapid chloride permeability rcp test is an electrical test used to estimate the durability of concrete. What are the factors affecting the durability of concrete. Factors affecting the durability of concrete repair. Testing concrete mix to predict durability construction canada. Factors affecting concrete strength online civilforum.
Pdf the durability of reinforced concrete is influenced by those physical characteristics of concrete that control the diffusion of gases, such as. Some of the commonly used scms are flyash, silica fume and metakaoline. Nowadays opc is widely used and it is the costly ingredient in the production. Factors affecting durability of concrete pdf composite. The addition of scm to concrete reduces the heat of hydration and extends the service life in structures by improving both long term durability and strength. Factors affecting durability of concrete pdf durability of concrete concrete durability has been defined by the american concrete institute as its resistance to weathering action, chemical nditions, become a critical factor for crack prevention in mass concrete. The rate of hydration reaction is temperature dependent. Durability aspects of standard concrete m vijaya sekhar reddy1, i v ramana reddy2, k madan mohan reddy3 and c m ravi kumar4 in todays competitive environment it is becoming important to reduce the construction cost in one or other way. It normally refers to the duration or life span of troublefree performance. Factors affecting durability of concrete surfaces transportation. Durability of concrete types of durability and factors affecting. It is generally true that concrete structures need.
Low unit weight, low permeability, high absorption, better thermoinsulating capacity and excellent durability of lwac are its prominent characteristics. Different concretes require different degrees of durability depending on the exposure environment and properties desired. Factors affecting durability of concrete pdf free download as pdf file. What is concrete shrinkage and what are the factors. Workability is a property of freshly mixed concrete, and a concrete is a mixture of ce.
The results at 90 days age indicate that joint finish, mix proportions and sand type are significant factors affecting durability. Traditional concrete is a composite, which is made of aggregate, portland cement and water. Therefore, besides building material mechanical properties and the cost, the structural designer also need to focus on the durability of reinforced concrete. Voids in concrete can be filled with air or with water. Many factors can influence that life span, however poor concrete practices and lowquality materials can cut those lifespans by decades. Lightweight aggregate concrete lwac has been used extensively for structural applications for many years. Factors affecting durability of concrete aggregate research. Impairs watertightness of concrete cover to steel and provides an access for aggressive chemicals, affecting durability of concrete. Durability of reinforced concrete structures,theory vs practice.
Introduction concrete the man made rock is the most widely used construction material. Sep 19, 2014 durability is the key concretes durability is defined by its ability to resist weathering action and chemical attack, while maintaining the desired engineering properties. Durability of concrete, factors and cracks in concrete youtube. This objective then can be divided into more small objectives by dividing it into the experiment that will be done which are. Factors affecting the durability of concrete and the. The durability of cement is defined as its ability to resist weathering action, chemical attack, abrasion, or any other process of deterioration. Strength and durability evaluation of recycled aggregate concrete. Durability of concrete factors affecting durability of concrete. This means that the concrete kept at higher temperature will gain strength more quickly than a similar concrete kept at a lower temperature. Critical factors affecting asphalt concrete durability. The objective of the research is mainly to check the factors affecting workability of concrete incorporating pfa. Air voids are on obvious and easily visible example of pores in concrete. More than 80,000 crores cum of concrete are poured every year.
Concrete in contact or buried under nonaggressive soilground water. Measuring the durability of concrete to determine its longevity in. This will definitely damages the concrete structure and durability will be reduced. Concrete usually has two varieties of pores, which establish extend of permeability. The definition of lightweight concrete in other counties might slightly be different, for instance, according to norway code the concrete is assumed to be lightweight concrete if its saturated surface dry density is equal or greater than 1800 kgm 3 and its compression strength should not surpass 85 mpa. And the chloride attack is a major durability problem affecting concrete structures in the marine and island environment 9 11.
When it comes to concrete durability, engineers should not rely solely on specifying a minimum compressive strength, maximum watercement ratio, minimum cementitious content and air entrainment. Durability of reinforced concrete structures,theory vs. Factors affecting durability of concrete 27th january 2010 14th march 2016 concrete durability has been defined by the american concrete institute as its resistance to weathering action, chemical attack, abrasion and other degradation processes. According to a formula, when the watercement ratio equal, concrete produced by high.
Quality control in concrete and durability factors. This paper presents results of the durability characteristic properties of. Most of the general factors affecting concrete durability are captured above but with sea water, attack of chloride and sulphate, including the exposure condition. Due to the use of inappropriate materials, poor construction practices, insufficient curing, andor improper mix designs, many structures show serious premature deterioration. Learn durability of concrete, factors affecting durability of concrete and causes of cracks in concrete in simple language with effective explanation.
Durability of concrete factor affecting durable concrete. What is concrete strength and what are the factors. Low permeability and shrinkage are two performance characteristics of concrete that can. Factors affecting durability of lightweight concrete and its. Factors affecting bond between repairing con crete and. Durability of concrete may be defined as the ability of concrete to resist weathering action, che. This does not mean that they do not contain interconnected network of capillaries, but these capillaries are so fine that.
To investigate the paste consistency of cement plus pfa. Pdf durability of concrete structures researchgate. Concrete surfaces protected against weather or aggressive conditions,except those situated in coastal area. Durability and permeability of concrete linkedin slideshare. Factors affecting strength of concrete the constructor.
Effect of silt fines on the durability properties of concrete. For asphalt concrete mixtures, durability refers to the ability of the mixture to resist deterioration as it ages. Factors affecting durability of concrete pdf composite material. Unharden concreting getting wet is a severe issue in terms of the durability of concrete and continuous periodic wetting and drying due to the rain is not considered as a very highrisk factor affecting durability of concrete. Reinforced concrete is widely used in building structures.
In addition to strength of concrete another factor, environmental condition or exposure condition has become an important consideration for durability. Repointing mortars should be durable, practical in application e. Factors that affect cost estimates for concrete construction. Factors affecting strength and durability of concrete made with various cements k. May, 2018 the strength of concrete is affected by various factors including its ingredients, environmental factors, postprocesses or works, and so on. Pdf physical and chemical characteristics affecting the durability. Review of factors affecting the durability of repointing mortars for older masonry a h p maurenbrecher 1, k trischuk 2, m z rousseau 3 abstract the selection of repointing mortars for older masonry in the canadian climate is a subject of debate. Impact of wc ratio on durability there is a tremendous change in the micro structure of concrete made with highwc ratio and lowwc ratio. Pdf physical and chemical characteristics affecting the.
Durability is defined as the capability of concrete to resist weathering action, chemical attack and abrasion while maintaining its desired engineering properties. Strength and durability evaluation of recycled aggregate concrete sherif yehia, kareem helal, anaam abusharkh, amani zaher, and hiba istaitiyeh received october 9, 2014, accepted april 6, 2015, published online may 14, 2015 abstract. Mix must be designed to ensure cohesion and prevent segregation and bleeding. Improving durability by more careful crack control improving durability by more careful crack control nonstructural cracks. It appears, therefore, that other factors must be considered as affecting abrasion resistance, and compressive strength alone cannot be used as a criterion for durable concrete. How the cement type affects the concrete strength and durability. The volumetric changes of concrete structures due to the loss of moisture by evaporation is known as concrete shrinkage or shrinkage of concrete. Strength and durability evaluation of recycled aggregate. To have a sustainable concrete structure, durability is key. Factors affecting strength and durability of densified. Vaysburd construction and building materials 1994 vol. These are known as capillary pores with a width ranging between 0. The water used in concrete mix also affects the durability of concrete. Costs of materials and supplies and the associated shipping charges influence the cost of any concrete construction project.
Effects of reinforced concrete durability factors mainly include corrosion of steel in reinforced. What are the main factors affecting the durability of concrete in. The mixing of these materials in specified proportions produces concrete. In the united states, quality work resulting in dense impervious concrete was an appropriate response while the use of blastfurnace slag cements met with favor in several european countries. Increasing aggregate size increases the strength of the concrete. The importance of the factors affecting concrete shrinkage. Factors affecting the durability of concrete bridge decks. Durability is the key concretes durability is defined by its ability to resist weathering action and chemical attack, while maintaining the desired engineering properties. It is utilized in the design of prestressed concrete design.
Concrete is the most commonused construction material in the modern world. In addition, both cement type and joint finish interact with sand type. Durability of concrete factor affecting durable concrete gharpedia. Efflorescence in concrete occurs due to moisture, which will converts salts into soluble solutions and when it evaporates salts become crystallized on the concrete surface. Durable concrete will retain its original form, quality, and serviceability when exposed to environment. Use of inappropriate materials, poor construction practices, curing and mix designs, results in concrete structures often showing serious premature deterioration. Durability durability is the ability to last a long time without significant deterioration. Factors affecting strength and durability of concrete made. Research on factors affecting reinforced concrete durability. Jan 14, 2018 learn durability of concrete, factors affecting durability of concrete and causes of cracks in concrete in simple language with effective explanation. Testing concrete mix to predict durability construction.
Sep 16, 20 compressive strength of concrete varies from 10nmm2 to 500nmm2 for ultra high strength concrete 20008000 psi. Durability of concrete types of durability and factors. Durability is the capacity to keep going quite a while without huge disintegration. Durability of concrete, factors and cracks in concrete. Jan 11, 2017 the concrete durability has been defined by american concrete institute aci as its resistance to the weathering activities, different chemical attack, scratch and other dilapidation processes and activities. If the temperature increases the reaction also increases. Normally, potable water is recommended for making concrete. What are those factors, lets find outmaterial costs. Attack by a natural or industrial liquids or gases. The definition of lightweight concrete in other counties might slightly be different, for instance, according to norway code the concrete is assumed to be lightweight concrete if its saturated surface dry density is equal or greater than 1800 kgm 3 and its compression strength should not surpass 85 mpa lightweight concrete is produced by blending cement, water, fine aggregate, and. However, due to its corrosion, deterioration loss is more and more outstanding. Factors affecting bond between repairing concrete and concrete substrate magda i.
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