3 Soundness – The soundness of cement refers to the stability of the volume change in the process of setting and hardening. If the volume change is unstable after setting and hardening, the concrete structures will crack, which can affect the quality of buildings or even cause serious accidents, known as poor dimensional stability.
The cement product whose dimensional stability is poor will be disposed as spoiled product, not used in projects. The reasons for poor dimensional stability are: the free calcium oxide ( f -CaO) in the clinker is too much, or the free magnesium oxide in the clinker ( f -MgO) is quite a little, or the gypsum mixed in the clinker is excessive.
f -CaO and f -MgO in the clinker are all sintered, so their ageing speed is very slow. They start ageing slowly after the setting and hardening. CaO + H 2 O = Ca OH 2 MgO + H 2 O = Mg OH 2 In the ageing process, there is volume expansion which causes the cracking of cement.
The excessive amount of gypsum will react with the solid calcium aluminate hydrate to generate crystals of calcium sulfoaluminate hydrate. Thus, the volume will expand 1.5 times, which leads to the cracking of cement paste matrix. The national standards require: boiling method can be used to inspect the poor dimensional stability of the cement caused by the free CaO.
The so-called boiling method includes Pat test and Le Chatelier test. Pat test is to make the cement paste of normal consistency into cement cake, boil it for 3 h, and then observe it by naked eyes. If there is no crack and no bending by ruler inspection, it is called qualified soundness.
Le Chatelier test is to measure the expansion value after the cement paste is boiled and get hardened on Le Chatelier needles. If the expansion value is within the required value, its stability is qualified. If there is contradictory between the results measured by Pat test and Le Chatelier test, Le Chaterlier test should prevail.
The hydration of free magnesium oxide is slower than that of free calcium oxide. Therefore, its harm can be inspected only by autoclave test. The harm of gypsum will be found by immersing in room-temperature water for a long time. Then the poor dimensional stability caused by magnesium dioxide and gypsum is inconvenient to be tested rapidly.
Thus, they should be controlled strictly in the production of cement. The national standards require: the content of free magnesium oxide in cement should not be more than 5.0%, and the content of sulfur trioxide in slag cement should not be more than 4.0% and that in other kinds of cement should not exceed 3.5%.
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Contents
- 1 What is meaning of soundness of cement Mcq?
- 2 What are the causes of soundness of cement?
- 3 What is sound and unsound cement?
- 4 What is the best definition of soundness?
- 5 What is the difference between soundness and unsoundness of cement?
- 6 How do you identify soundness?
- 7 What do you mean by soundness of aggregate?
- 8 What is hydration of cement Mcq?
- 9 What is soundness and unsoundness?
What is meaning of soundness of cement Mcq?
Free Gujarat Engineering Service 2019 Official Paper (Civil Part 1) 150 Questions 150 Marks 90 Mins Soundness Test: Expansion of cement is measured/computed by soundness test. Soundness means the ability to resist volume expansion and it is indication durability.
The unsoundness in cement is due to the presence of an excess of free lime than that could be combined with acidic oxide at the kiln. The soundness of cement may be determined by two methods, namely Le-Chatelier method and autoclave method. The Le-Chatelier test detects unsoundness due to free Lime only.
This method of testing does not indicate the presence and after effect of the excess of magnesia. As per Indian Standard specification, if the content of magnesia is greater than 3% in cement then Autoclave Test is performed which is sensitive to both Lime and Magnesia.
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Candidates with a Graduation degree as the basic GPSC Engineering Services Eligibility Criteria are eligible to appear for the recruitment process. The finally selected candidates will get a salary range between Rs.53100 to Rs.208700.
What is the meaning of soundness of cement Examveda?
Concrete Technology Questions and Answers – Soundness of Aggregates This set of Concrete Technology Multiple Choice Questions & Answers (MCQs) focuses on “Soundness of Aggregates”.1. What is soundness? a) Soundness of cement is the property by virtue of which the cement does not undergo any appreciable expansion b) Soundness of cement is the property by virtue of which the cement does undergo any appreciable expansion c) Soundness of cement is the property by virtue of which the cement does not undergo any appreciable contraction d) Soundness of cement is the property by virtue of which the cement does undergo any appreciable contraction View Answer Answer: a Explanation: Soundness of cement is the property by virtue of which the cement does not undergo any appreciable expansion.2.
- Which apparatus we need to find soundness? a) Le Chatelier b) Vicat’s apparatus c) CTM d) Pat test View Answer Answer: a Explanation: This test is performed with the help of Le Chatelier apparatus as shown in figure below.
- It consists of a brass mould of diameter 30 mm and height 30 mm.3.
- Why do we need to find soundness? a) To detect the uncombined lime in cement b) To detect the combined lime in cement c) To detect the combined alumina in cement d) To detect the uncombined alumina in cement View Answer Answer: a Explanation: Soundness Test on Cement.
Soundness Test onCement is carried out to detect the presence of uncombined lime in cement.4. What is the maximum size of split? a) 1mm b),5mm c) 10mm d) 2mm View Answer Answer: b Explanation: There is a split in mould and it does not exceed 0.50 mm.
On either side of split, there are two indicators with pointed ends. The thickness of mould cylinder is 0.50 mm.5. Le Chatelier apparatus consist of _ a) Brass mould b) Steel mould c) Aluminum mould d) Wooden mould View Answer Answer: a Explanation: Le Chatelier apparatus consist of brass mould with the diameter of 30mm and height of 30 mm.
Become Now! 6. When the cement paste is filled in mould and kept in water. Then what should be the temperature of water? a) 24-35°C b) 20°C c) 30-40°C d) 50°C View Answer Answer: a Explanation: A small weight is placed at top and the whole assembly is submerged in water for 24 hours.
The temperature of water should be between 24°C to 35°C.7. Expansion should not be more than _ a) 5mm b) 10mm c) 5cm d) 10cm View Answer Answer: b Explanation: The difference between the two readings indicates the expansion of cement and it should not exceed 10 mm.8. If the Y is the reading of sand surface (ml) then what is the percentage of bulking? a) % of bulking x 100 b) % of bulking x 100 c) % of bulking x 100 d) % of bulking x 100 View Answer Answer: b Explanation: % of bulking x 100.
Report the percentage bulking of the sand to the nearest whole number.9. What is the size of caliper? a) 30cm b) 50cm c) 30mm d) 40mm View Answer Answer: a Explanation: Generally the size of the caliper is 30cm with the least count of,5mm with the 100ml of measuring cylinder.10.
- What is the standard value of expansion for super sulphated cement? a) 10mm b) 5mm c) 1mm d),5mm View Answer Answer: b Explanation: It is the standard value for super sulphated cement under IS:6909-1990.
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What are the causes of soundness of cement?
01. Excess Lime – Soundness of cement is affected by the presence of excess lime (CaO) in the cement. This excess lime hydrates very slowly and forms slaked lime that occupies a larger volume than the original free calcium oxide. The slow hydration process, therefore, affects the properties of hardened concrete.
What is sound and unsound cement?
How to Detect Unsound Concrete – Visually inspecting the surface will reveal the worst of the damage: the cracks, spalling, scaling and crushed delaminations, but the full extent of the unsound concrete is not always apparent. Perhaps the easiest thing to do is to tap around visibly weak areas with a hammer.
If the head of the hammer bounces, the concrete’s compressive strength is good. If the hammer indents and pulverizes the surface, the concrete is unsound and should come out. Dragging a screwdriver across the surface can also expose unsound concrete. If it leaves a shiny white streak, the concrete is sound.
If it scratches off powder, the concrete is unsound. Cases where pockets of air, water or unwetted material have formed under the surface are not so easy to detect: the surface may be sound enough to pass the hammer or screwdriver test, but structurally compromised.
What is the best definition of soundness?
/ˈsaʊndnəs/ the quality of being sensible; the fact that something can be relied on and will probably give good results. soundness of judgement. financial soundness opposite unsoundness (1)
What is another word for soundness?
Contexts ▼ The quality or state of being in good health The capacity of an object or substance to withstand great force or pressure The measure by which an idea or argument can be relied upon or trusted The breadth or comprehensiveness of something more ▼ Noun ▲ The quality or state of being in good health fitness health healthiness robustness wholeness wellness verdure wholesomeness sap heartiness vigour UK vigor US good condition strength healthfulness well-being lustiness hardiness salubrity haleness salubriousness bloom hardihood physical fitness good shape shape energy complexion fettle good trim clean bill fine feather condition sturdiness ruggedness trim nick good health kilter fine fettle state of health wellbeing prime pink constitution form euphoria eupepsia tone good physical condition nimbleness sprightliness spryness cheerfulness enthusiasm fervor US gusto fervour UK stamina state physical stalwartness toughness athleticism tonicity muscularity physical condition huskiness good kilter top form beauty endurance order repair keeping estate whack working order vitality commission situation life way state of repair sound condition status build aspect appearance physical shape more ❯ “In a person born with both soundness of mind and body, the mind will not become insane so long as the body retains its original health.” Noun ▲ The capacity of an object or substance to withstand great force or pressure sturdiness durability strength firmness integrity intactness solidity stability integrality structural integrity solidness toughness robustness hardness security reliability steadiness sureness dependability durableness imperishability fastness immovability immobility stoutness lastingness substantiality stableness resilience safety impregnability wholeness starch hardiness strongness safeness secureness longevity heftiness resoluteness enduringness indestructibility impenetrability compactness rigidity imperviousness impermeability certainty powerfulness resistance ability to last safe future assured future more ❯ “The continued neglect of repairs will impair the soundness of the structure and create a hazard to its safety as a place of residence.” Noun ▲ The measure by which an idea or argument can be relied upon or trusted dependability reliability trustworthiness accuracy authenticity unassailability dependableness infallibility reliableness trustability solidity solidness validity believability plausibility likelihood credibility tenability possibility prospect probability sureness satisfactoriness acceptability credibleness chance responsibility plausibleness faithfulness steadiness integrity constancy creditableness creditability verisimilitude reasonableness conceivability correctness rightness exactitude safety irrefutability steadfastness loyalty staunchness authority weight cogency impressiveness authoritativeness veracity fidelity truth factualness veridicality believableness sincerity believeableness genuineness certainty surety certitude decisiveness verity truthfulness definiteness positiveness assuredness factuality unequivocalness conclusiveness unambiguousness faultlessness impeccability flawlessness precision exactness decidedness absoluteness honesty legitimacy candour UK truism trueness fact realism accurateness gospel factualism candor US rectitude sooth facticity cast-iron certainty more ❯ “We have always had misgivings as to the soundness of this theory.” Noun ▲ The breadth or comprehensiveness of something thoroughness comprehensiveness completeness depth breadth range exhaustiveness extensiveness fullness generality inclusiveness all-inclusiveness scope ubiquity universality extent scale compass amplitude width broadness catholicity prevalence commonness magnitude sweep vastness degree realm ambit sweepingness reach span dimension orbit length confines coverage gamut immensity generalization US totality richness inclusivity popularity expansiveness immenseness compendiousness generalisation UK miscellaneity acceptedness spectrum sphere purview limit boundaries field jurisdiction capacity stretch horizon dimensions area expanse size extension spread proportions territory confine radius margin remit bounds proportion competence outlook run bracket wideness region terms of reference sphere of influence field of reference largeness greatness “Recognized experts will be engaged to ensure the methodological soundness of the report.” Noun ▲ The quality of being clear, logical, and convincing cogency persuasiveness effectiveness persuasion force authority forcefulness efficacy power weight strength conclusiveness convincingness influence potency validity punch point suasiveness plausibility foundation impressiveness authoritativeness eloquence logic impact credibility rationality reasonableness intensity vigor US vigour UK dynamism logicality coherence unanswerability validness articulateness clarity conviction lucidity methodicalness orderliness consistency good organization substance grounds gravity value significance efficaciousness might effect bite competence capability ability dominance determination gumption legality emphasis sapience legitimacy sustainability viability defensibility justifiability believability substantiality reliability authenticity bona fides indisputability candidness right truth realness truthfulness intelligibility genuinity genuineness comprehensibility reason articulacy good sense weightiness consequence clout efficacity efficiency performance importance moment sway pull momentousness import success productiveness usefulness signification powerfulness effectualness virtue effectuality suasion appeal smoothness inducement slickness control decisiveness verve finality wallop definiteness irrevocability inevitability energy lawfulness fruitfulness correctness function advantage fierceness assertiveness aggressiveness capacity potential benefit successfulness progress facility potence helpfulness use constructiveness agency progression vividness richness legal acceptability contractual nature binding nature activity instrumentality operation edge effectivity greatness grandeur leverage muscle carrying on reverberation bearing imprint mark seriousness footprint priority relevance notability worth preponderancy preponderance stress materiality distinction precedence paramountcy teeth consideration credit prestige heft account upshot calibre UK standing significancy caliber US beef mana magnitude impression splash pith in juice forcibleness more ❯ Noun ▲ The state of having a normal healthy mind saneness sanity reason sense mind wits intelligence rationality marbles judgement UK judgment US understanding lucidity daylights balance wit sagacity lucidness acumen head comprehension judiciousness prudence reasonableness levelheadedness stability normality cogency soberness clear-headedness common sense good judgment clear mind healthy mind sound mind right mind sensibleness wisdom logic good sense sound judgment practicality shrewdness gumption coherence horse sense nous discernment intellection sapience logical thought insight discretion astuteness smarts reasoning sharpness ratiocination perspicacity perceptiveness pragmatism cognition savvy canniness knowledge sageness brains experience rationalness good judgement soundness of mind good reasoning savoir faire perception penetration intellect thought discrimination intellectuality percipience circumspection perspicuity foresight thoughtfulness erudition tact vigilance perceptivity heedfulness enlightenment acuity intuition wariness watchfulness perspicaciousness apprehension mentality providence consideration tactfulness sagaciousness forethought cleverness level-headedness ingenuity arguteness commonsense scientific thinking clear thinking presence of mind clear-sightedness awareness sophistication capacity grasp quickness acuteness keenness incisiveness genius know-how sharp-wittedness powers of discernment powers of reasoning cognitive faculties native wit logicality rationale realism mental health sound judgement good eye grey matter common propriety advisability practicability moderation smartness learning worldliness soundness of judgment maturity poise caution policy heed pansophy mental balance worldly wisdom reasonability logicalness matter-of-factness right-mindedness balance of mind inference induction chain of thought course of thought syllogistic reasoning train of thought good reason antithesis and synthesis discreetness intuitiveness resourcefulness vision enterprise initiative capability cool mother wit sweet reason cop on native intelligence sound sense subtlety refinement sensitivity delicacy knowingness brainpower skill care diplomacy appreciation finesse brilliance brightness farsightedness taste cognizance profundity grip foxiness caginess cageyness good taste ability cunning adroitness alertness hardheadedness quick-wittedness mastery delicatesse brain control sensibility precocity distinction expertise gray matter IQ braininess loaf prescience urbanity precaution cultivation selectivity dexterity savoir-faire carefulness ingeniousness conception consciousness polish aptness observation decorum mental capacity deftness education insightfulness headpiece separation clearness culture percipiency recognition astucity smoothness familiarity sensitiveness scholarship presence learnedness aptitude suavity realization US information expertness apperception solidity intellectual capacity repose politicness mindfulness senses imagination what it takes politesse creativity observance foresightedness forehandedness kop realisation UK omniscience brain cells mental faculties tastefulness eye nose preference differentiation difference decision bias proficiency adeptness artfulness depth profoundness skilfulness psyche selectiveness calculation considerateness amenity address deliberation guile accuracy flair responsiveness the right stuff assimilation feeling deep insight upper storey planning connoisseurship schooling brainbox spirit aestheticism acquaintance sentience provision ken intimacy faculties acquaintanceship faculty better understanding mental agility intellectual power knowing inside out I.Q.
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Why do we need soundness test in cement?
Significance of Soundness Test on Cement – Cement is a composition of lime, silica, alumina, magnesia, alkaline, sulfur trioxide, iron oxide, and calcium sulfate. Among which, lime constitutes 60 to 70%. Hence, a cement deficient in lime will set quickly and will affect the property of the cement.
What is meaning of soundness of cement cos 305 A *?
Basic Civil Engineering Questions and Answers – Properties of Cement This set of Basic Civil Engineering Multiple Choice Questions & Answers (MCQs) focuses on “Properties of Cement”.1. Why is natural cement used very limitedly? a) Brown in Colour b) Standard consistency is not met with c) Sets too quickly d) Particle size is too fine View Answer Answer: c Explanation: Natural cement sets very quickly after the addition of water and hence it is not quite workable.
Artificial cement is preferred over this.2. Who invented Portland cement and in which year? a) William Aspdin, 1824 b) William Aspdin, 1840s c) Joseph Aspdin, 1840s d) Joseph Aspdin, 1824 View Answer Answer: b Explanation: Joseph Aspdin patented Portland cement in 1824. William Aspdin, his son is regarded as the inventor of modern Portland cement due to his developments in 1840s.3.
What is the average particle size of cement? a) 15 microns b) 45 microns c) 75 microns d) 100 microns View Answer Answer: a Explanation: Approximately 95% of cement particles are smaller than 45 microns and the average particle size is 15 microns. Note: Join free Sanfoundry classes at or 4.
What is the meaning of soundness of cement? a) Ability to flow when mixed b) Ability to make ringing noise when struck c) Ability to form strong and sound structure d) Ability to retain volume after setting. View Answer Answer: d Explanation: When cement paste hardens and sets, it should not undergo any volume change.
Soundness ensures this and is tested using Autoclave expansion test.5. Time elapsed from the instance of adding water until paste ceases to behave as fluid is called: a) Initial setting time b) Final setting time c) Intermediate setting time d) Absolute setting time View Answer Answer: a Explanation: Final setting time is the time required for cement paste to reach a certain state of hardness.
Option c and d does not exist. Take Now! 6. Which of the below mentioned is not a result of field test performed on cement? a) There should not be any lumps b) It should feel cold when you put your hand in bag of cement c) The colour should be blackish grey d) It should not be gritty when rubbed with finger View Answer Answer: c Explanation: The colour of cement is normally grey with a greenish tint.
There are different shades – lighter and darker, but it does not go as dark as blackish grey.7. Which equipment is used to test the setting time of cement? a) Core cutter b) Vibrator c) Universal testing machine (UTM) d) Vicat apparatus View Answer Answer: d Explanation: Core cutter is used to determine dry density of soil.
- Vibrator is used in sieve analysis.
- UTM can be used to test various parameters – tension, bending, shear of various materials.
- Vicat apparatus consists of a needle, used to penetrate the cement paste sample.8.
- What is the initial setting time of cement? a) 1 hour b) 30 minutes c) 15 minutes d) 30 hours View Answer Answer: b Explanation: As per IS code 4031-part 5, the initial setting time of cement is minimum of 30 minutes.
After this cement will start losing its plasticity and will not be workable.9. Use of coarser cement particles leads to: a) Low durability b) Higher strength c) Low consistency d) Higher soundness View Answer Answer: a Explanation: For coarser particles, hydration starts on the surface of particles, hence, it might not be completely hydrated.
This causes low strength and low durability.10. Wet cement can cause severe skin burns if not washed off with water immediately. a) True b) False View Answer Answer: a Explanation: Cement is highly alkaline and setting process is exothermic. Wet cement is strongly caustic and causes skin burns. Similarly, dry cement causes eye or respiratory irritation, when it comes in contact with mucous membranes.11.
Green cement is: a) Green coloured cement b) Cement mixed with plant products c) Cement mixed with recycled materials d) Cement mixed with green algae View Answer Answer: c Explanation: Green cement is a cementitious material which employs the use of optimized recycled materials.
- These can meet or even exceed the functional performance of Portland cement.12.
- What is the depth the needle in Vicat apparatus should penetrate into the cement paste in consistency test? a) 33-35 cm from bottom of the mould b) 33-35 mm from top of the mould c) 33-35 cm from top of the mould d) 33-35 mm from bottom of the mould View Answer Answer: b Explanation: The best procedure has been clearly mentioned in IS 4031 Part 4.
According to the code, 33-35mm depth of penetration is ideal. Sanfoundry Global Education & Learning Series – Basic Civil Engineering. To practice all areas of Basic Civil Engineering,, Next Steps:
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What is soundness of casting?
Soundness: Measure of impurities and/or discontinuities such as sand inclusions, slag inclusions, macro porosity (pores greater than 50 nm in diameter) and shrinkage.
What is brick soundness?
6. Soundness Test of Bricks – Soundness test of bricks shows the nature of bricks against sudden impact. In this test, 2 bricks are chosen randomly and struck with one another. Then sound produced should be clear bell ringing sound and brick should not break. Then it is said to be good brick.
What is soundness and unsoundness?
template.1 Validity and Invalidity, Soundness and Unsoundness The task of an argument is to provide statements (premises) that give evidence for the conclusion. There are two basic kinds of arguments. Deductive argument: involves the claim that the truth of its premises guarantees the truth of its conclusion; the terms valid and invalid are used to characterize deductive arguments.
A deductive argument succeeds when, if you accept the evidence as true (the premises), you must accept the conclusion. Inductive argument: involves the claim that the truth of its premises provides some grounds for its conclusion or makes the conclusion more probable; the terms valid and invalid cannot be applied.
Valid: an argument is valid if and only if it is necessary that if all of the premises are true, then the conclusion is true; if all the premises are true, then the conclusion must be true; it is impossible that all the premises are true and the conclusion is false.
Invalid: an argument that is not valid. We can test for invalidity by assuming that all the premises are true and seeing whether it is still possible for the conclusion to be false. If this is possible, the argument is invalid. Validity and invalidity apply only to arguments, not statements. For our purposes, it is just nonsense to call a statement valid or invalid.
True and false apply only to statements, not arguments. For our purposes, it is just nonsense to call an argument true or false. All deductive arguments aspire to validity. If you consider the definitions of validity and invalidity carefully, you’ll note that valid arguments have the following important property: valid arguments preserve truth.
- If all your premises are true and you make a valid argument from them, it must be the case that whatever conclusion you obtain is true.
- We shall see below, however, that valid arguments do not necessarily preserve truth value: it is entirely possible to argue validly from false premises to a true conclusion).
Sound: an argument is sound if and only if it is valid and contains only true premises. Unsound: an argument that is not sound. Counterexample: an example which contradicts some statement or argument (ex. a counterexample to the statement “All fifteen year-olds have blue hair” would be a fifteen-year-old without blue hair); for an argument, a counterexample would be a situation in which the premises of the argument are true and the conclusion is false; counterexamples show statements to be false and arguments to be invalid.
What is the difference between soundness and unsoundness of cement?
Soundness of cement is the ability of a hardened paste to retain its volume after setting. A cement is said to be unsound (i.e., having lack of soundness) if it is subjected to delayed destructive expansion. Unsoundness of cement is due to presence of excessive amount of hard-burned free lime or magnesia.
What are the types of sound?
Types of Sound – There are many different types of sound including, audible, inaudible, unpleasant, pleasant, soft, loud, noise and music. You’re likely to find the sounds produced by a piano player soft, audible, and musical. And while the sound of road construction early on Saturday morning is also audible, it certainly isn’t pleasant or soft.
How do you identify soundness?
A deductive argument is said to be valid if and only if it takes a form that makes it impossible for the premises to be true and the conclusion nevertheless to be false. Otherwise, a deductive argument is said to be invalid, A deductive argument is sound if and only if it is both valid, and all of its premises are actually true,
- Otherwise, a deductive argument is unsound.
- According to the definition of a deductive argument (see the Deduction and Induction ), the author of a deductive argument always intends that the premises provide the sort of justification for the conclusion whereby if the premises are true, the conclusion is guaranteed to be true as well.
Loosely speaking, if the author’s process of reasoning is a good one, if the premises actually do provide this sort of justification for the conclusion, then the argument is valid, In effect, an argument is valid if the truth of the premises logically guarantees the truth of the conclusion.
- The following argument is valid, because it is impossible for the premises to be true and the conclusion nevertheless to be false: Elizabeth owns either a Honda or a Saturn.
- Elizabeth does not own a Honda.
- Therefore, Elizabeth owns a Saturn.
- It is important to stress that the premises of an argument do not have actually to be true in order for the argument to be valid.
An argument is valid if the premises and conclusion are related to each other in the right way so that if the premises were true, then the conclusion would have to be true as well. We can recognize in the above case that even if one of the premises is actually false, that if they had been true the conclusion would have been true as well.
Consider, then an argument such as the following: All toasters are items made of gold. All items made of gold are time-travel devices. Therefore, all toasters are time-travel devices. Obviously, the premises in this argument are not true. It may be hard to imagine these premises being true, but it is not hard to see that if they were true, their truth would logically guarantee the conclusion’s truth.
It is easy to see that the previous example is not an example of a completely good argument. A valid argument may still have a false conclusion. When we construct our arguments, we must aim to construct one that is not only valid, but sound, A sound argument is one that is not only valid, but begins with premises that are actually true,
- The example given about toasters is valid, but not sound.
- However, the following argument is both valid and sound: In some states, no felons are eligible voters, that is, eligible to vote.
- In those states, some professional athletes are felons.
- Therefore, in some states, some professional athletes are not eligible voters.
Here, not only do the premises provide the right sort of support for the conclusion, but the premises are actually true. Therefore, so is the conclusion. Although it is not part of the definition of a sound argument, because sound arguments both start out with true premises and have a form that guarantees that the conclusion must be true if the premises are, sound arguments always end with true conclusions.
- It should be noted that both invalid, as well as valid but unsound, arguments can nevertheless have true conclusions.
- One cannot reject the conclusion of an argument simply by discovering a given argument for that conclusion to be flawed.
- Whether or not the premises of an argument are true depends on their specific content,
However, according to the dominant understanding among logicians, the validity or invalidity of an argument is determined entirely by its logical form, The logical form of an argument is that which remains of it when one abstracts away from the specific content of the premises and the conclusion, that is, words naming things, their properties and relations, leaving only those elements that are common to discourse and reasoning about any subject matter, that is, words such as “all,” “and,” “not,” “some,” and so forth.
- One can represent the logical form of an argument by replacing the specific content words with letters used as place-holders or variables.
- For example, consider these two arguments: All tigers are mammals.
- No mammals are creatures with scales.
- Therefore, no tigers are creatures with scales.
- All spider monkeys are elephants.
No elephants are animals. Therefore, no spider monkeys are animals. These arguments share the same form: All A are B; No B are C; Therefore, No A are C. All arguments with this form are valid. Because they have this form, the examples above are valid. However, the first example is sound while the second is unsound, because its premises are false.
Now consider: All basketballs are round. The Earth is round. Therefore, the Earth is a basketball. All popes reside at the Vatican. John Paul II resides at the Vatican. Therefore, John Paul II is a pope. These arguments also have the same form: All A’s are F; X is F; Therefore, X is an A. Arguments with this form are invalid.
This is easy to see with the first example. The second example may seem like a good argument because the premises and the conclusion are all true, but note that the conclusion’s truth isn’t guaranteed by the premises’ truth. It could have been possible for the premises to be true and the conclusion false.
- This argument is invalid, and all invalid arguments are unsound.
- While it is accepted by most contemporary logicians that logical validity and invalidity is determined entirely by form, there is some dissent.
- Consider, for example, the following arguments: My table is circular.
- Therefore, it is not square shaped.
Juan is a bachelor. Therefore, he is not married. These arguments, at least on the surface, have the form: x is F; Therefore, x is not G. Arguments of this form are not valid as a rule. However, it seems clear in these particular cases that it is, in some strong sense, impossible for the premises to be true while the conclusion is false.
- However, many logicians would respond to these complications in various ways.
- Some might insist–although this is controverisal–that these arguments actually contain implicit premises such as “Nothing is both circular and square shaped” or “All bachelors are unmarried,” which, while themselves necessary truths, nevertheless play a role in the form of these arguments.
It might also be suggested, especially with the first argument, that while (even without the additional premise) there is a necessary connection between the premise and the conclusion, the sort of necessity involved is something other than “logical” necessity, and hence that this argument (in the simple form) should not be regarded as logically valid.
- Lastly, especially with regard to the second example, it might be suggested that because “bachelor” is defined as “adult unmarried male”, that the true logical form of the argument is the following universally valid form: x is F and not G and H; Therefore, x is not G.
- The logical form of a statement is not always as easy to discern as one might expect.
For example, statements that seem to have the same surface grammar can nevertheless differ in logical form. Take for example the two statements: (1) Tony is a ferocious tiger. (2) Clinton is a lame duck. Despite their apparent similarity, only (1) has the form “x is a A that is F.” From it one can validly infer that Tony is a tiger.
- One cannot validly infer from (2) that Clinton is a duck.
- Indeed, one and the same sentence can be used in different ways in different contexts.
- Consider the statement: (3) The King and Queen are visiting dignitaries.
- It is not clear what the logical form of this statement is.
- Either there are dignitaries that the King and Queen are visiting, in which case the sentence (3) has the same logical form as “The King and Queen are playing violins,” or the King and Queen are themselves the dignitaries who are visiting from somewhere else, in which case the sentence has the same logical form as “The King and Queen are sniveling cowards.” Depending on which logical form the statement has, inferences may be valid or invalid.
Consider: The King and Queen are visiting dignitaries. Visiting dignitaries is always boring. Therefore, the King and Queen are doing something boring. Only if the statement is given the first reading can this argument be considered to be valid. Because of the difficulty in identifying the logical form of an argument, and the potential deviation of logical form from grammatical form in ordinary language, contemporary logicians typically make use of artificial logical languages in which logical form and grammatical form coincide.
In these artificial languages, certain symbols, similar to those used in mathematics, are used to represent those elements of form analogous to ordinary English words such as “all”, “not”, “or”, “and”, and so forth. The use of an artificially constructed language makes it easier to specify a set of rules that determine whether or not a given argument is valid or invalid.
Hence, the study of which deductive argument forms are valid and which are invalid is often called “formal logic” or “symbolic logic.” In short, a deductive argument must be evaluated in two ways. First, one must ask if the premises provide support for the conclusion by examing the form of the argument.
If they do, then the argument is valid. Then, one must ask whether the premises are true or false in actuality. Only if an argument passes both these tests is it sound, However, if an argument does not pass these tests, its conclusion may still be true, despite that no support for its truth is given by the argument.
Note: there are other, related, uses of these words that are found within more advanced mathematical logic. In that context, a formula (on its own) written in a logical language is said to be valid if it comes out as true (or “satisfied”) under all admissible or standard assignments of meaning to that formula within the intended semantics for the logical language.
- Moreover, an axiomatic logical calculus (in its entirety) is said to be sound if and only if all theorems derivable from the axioms of the logical calculus are semantically valid in the sense just described.
- For a more sophisticated look at the nature of logical validity, see the articles on ” Logical Consequence ” in this encyclopedia.
The articles on ” Argument ” and ” Deductive and Inductive Arguments ” in this encyclopedia may also be helpful.
What determines soundness?
Soundness: An argument is sound if it meets these two criteria: (1) It is valid. (2) Its premises are true. In other words, a sound argument has the right form AND it is true. Note #3: A sound argument will always have a true conclusion.
How do you prove soundness?
Proof of Soundness – To show that our proof system is sound, we prove something stronger: if \(φ_1, φ_2, \dots ⊢ ψ\) then \(φ_1, φ_2, \dots ⊨ ψ\), Assume \(φ_1, φ_2, \dots ⊢ ψ\), so that there exists a proof tree \(T\) terminating with this line. Note that proof trees are inductively defined structures, so we can actually do a meta-inductive proof on the structure of the object proof.
- For example, if the rule at the root of the tree is the and introduction rule:
- \ \]
- then there are valid proof subtrees ending in \(\cdots ⊢ φ\) and \(\cdots ⊢ ψ\), so we will inductively assume that \(\cdots ⊨ φ\) and \(\cdots ⊨ ψ\),
- We examine a few of the rules; the remaining cases are left as review exercises. We refer to the list of rules
- \(P(T)\) where \(T\) ends with law of excluded middle to show \(\cdots ⊢ φ ∨ ¬φ\), We wish to show that in any \(I\) satisfying the assumptions, \(I ⊨ φ ∨ ¬φ\), Well, \(φ\) is either T or F. If it is T, then the rule for evaluating \(∨\) says that \(φ∨¬φ\) evaluates to T, while if it is \(F\), then \(¬φ\) evaluates to true, and again we see that \(φ∨¬φ\) evaluates to T.
- \(P(T)\) where \(T\) ends with reductio ad absurdum:
\ \] We wish to show that in any interpretation \(I\) satisfying the assumptions \(A\), that \(I ⊨ ψ\), Inductively, we assume that \(I ⊨ φ\) and \(I ⊨ ¬φ\), But this is impossible, because \(φ\) either evaluates to T or F in \(I\), So the conclusion for all \(I\) satisfying \(A\), \(I ⊨ ψ\) is vacuously true: there are no interpretations satisfying \(A\),
\(P(T)\) where \(T\) ends with \(∧\) introduction:
\ \] We wish to show that in any interpretation \(I\) satisfying \(A\), that \(I ⊨ φ∧ψ\), We inductively assume \(I ⊨ φ\) and \(I ⊨ ψ\), The rules for evaluating \(φ∧ψ\) immediately show that \(I ⊨ φ∧ψ\) as required. The remaining cases are left as review exercises.
What is soundness and completeness?
Logical systems – In mathematical logic, a logical system has the soundness property if every formula that can be proved in the system is logically valid with respect to the semantics of the system. In most cases, this comes down to its rules having the property of preserving truth, The converse of soundness is known as completeness, A logical system with syntactic entailment and semantic entailment is sound if for any sequence of sentences in its language, if, then In other words, a system is sound when all of its theorems are tautologies, Soundness is among the most fundamental properties of mathematical logic. The soundness property provides the initial reason for counting a logical system as desirable. The completeness property means that every validity (truth) is provable.
- Together they imply that all and only validities are provable.
- Most proofs of soundness are trivial.
- For example, in an axiomatic system, proof of soundness amounts to verifying the validity of the axioms and that the rules of inference preserve validity (or the weaker property, truth).
- If the system allows Hilbert-style deduction, it requires only verifying the validity of the axioms and one rule of inference, namely modus ponens,
(and sometimes substitution) Soundness properties come in two main varieties: weak and strong soundness, of which the former is a restricted form of the latter.
How do you use soundness in a sentence?
Fortunately he was rescued, and the shock did not stay his return to mental soundness.
What does sound mean in logic?
10 Validity and Soundness A good argument is not only valid, but also sound. Soundness is defined in terms of validity, so since we have already defined validity, we can now rely on it to define soundness. A sound argument is a valid argument that has all true premises.
That means that the conclusion of a sound argument will always be true. Why? Because if an argument is valid, the premises transmit truth to the conclusion on the assumption of the truth of the premises. But if the premises are actually true, as they are in a sound argument, then since all sound arguments are valid, we know that the conclusion of a sound argument is true.
Compare the last two Obama examples from the previous section. While the first argument was sound, the second argument was not sound, although it was valid. The relationship between soundness and validity is easy to specify: all sound arguments are valid arguments, but not all valid arguments are sound arguments.
- Although soundness is what any argument should aim for, we will not be talking much about soundness in this book.
- The reason for this is that the only difference between a valid argument and a sound argument is that a sound argument has all true premises.
- But how do we determine whether the premises of an argument are actually true? Well, there are lots of ways to do that, including using Google to look up an answer, studying the relevant subjects in school, consulting experts on the relevant topics, and so on.
But none of these activities have anything to do with logic, per se. The relevant disciplines to consult if you want to know whether a particular statement is true is almost never logic! For example, logic has nothing to say regarding whether or not protozoa are animals or whether there are predators that aren’t in the animal kingdom.
What do you mean by soundness of aggregate?
Durability and Soundness The soundness test determines an aggregate ‘s resistance to disintegration by weathering and, in particular, freeze-thaw cycles. Aggregates that are durable (resistant to weathering) are less likely to degrade in the field and cause premature HMA pavement distress and potentially, failure.
- The soundness test repeatedly submerges an aggregate sample in a sodium sulfate or magnesium sulfate solution.
- This process causes salt crystals to form in the aggregate’s water permeable pores.
- The formation of these crystals creates internal forces that apply pressure on aggregate pores and tend to break the aggregate (Figure 1).
After a specified number of submerging and drying repetitions, the aggregate is sieved to determine the percent loss of material. Figure 1: Aggregate before (top) & after (bottom) the soundness test. The formation of salt crystals is supposed to mimic the formation of ice crystals in the field and could therefore be used as a surrogate to predict an aggregate’s freeze-thaw performance.
AASHTO T 104 and ASTM C 88: Soundness of Aggregate by Use of Sodium Sulfate or Magnesium Sulfate
What is meant by soundness of cement explain the procedure of testing soundness?
🕑 Reading time: 1 minute Soundness of cement can be defined as its ability to retain its volume after it gets hardened. This means that a properly sound cement will undergo minimum volume change after it converts into the hardened state. In the soundness test of cement, we determine the amount of excess lime.
What is hydration of cement Mcq?
Concept: The four major compounds which are constituents of cement are: a) Tricalcium silicate (C 3 S): 3CaO.SiO 2 b) Dicalcium silicate (C 2 S): 2CaO.SiO 2 c) Tricalcium Aluminate (C 3 A): 3CaO.Al 2 O 3 d) Tetra-calcium Alumino Ferrite (C 4 AF): 4CaO.Al 2,Fe 2 O 3 These compounds are also known as Bogue Compounds,
C 3 S readily reacts with water, produces more heat of hydration and is responsible for the early strength of concrete. C 2 S hydrates more slowly and produce less heat of hydration and are responsible for later strength of concrete.
1. Tricalcium Silicate C 3 S – (25 – 50%) – Normally 40%
It is considered as the best cementing material and is well-burnt cement. It hydrates rapidly generating high heat and develops an early hardness and strength. Raising of C 3 S content beyond the specified limits increases heat of hydration and solubility of cement in water. The heat of hydration is 500 J/g,
2. Dicalcium Silicate (C 2 S) – (25 – 40%) – (Normally 32%)
It hydrates and hardens slowly and takes a long time to add to the strength (after a year or more) i.e. it is responsible for ultimate strength, It imparts resistance to chemical attack. Raising of C 2 S content renders clinkers harder to grind, reduces early strength, decreases resistance to freezing and thawing at an early age and decreases heat of hydration. At an early age, less than a month, C 2 S has little influence on strength and hardness. While after one year, its contribution to the strength and hardness is proportionately almost equal to C 3 S. The heat of hydration is 260 J/g.
3. Tricalcium Aluminate (C 3 A) – (5 – 11%) -(Normally 10.5%).
It rapidly reacts with water and is responsible for the flash set of finely grounded clinkers. The rapidity of action is regulated by the addition of 2-3% of gypsum at the time of grinding the cement. It is most responsible for the initial setting, the high heat of hydration and has a greater tendency to volume changes causing cracking. Raising the C 3 A content reduces the setting time, weakens resistance to sulphate attack and lowers the ultimate strength, heat of hydration and contraction during air hardening. The heat of hydration of 865 J/g.
4. Tetracalcium Alumino Ferrite – (C 4 AF 8 – 14%) (Normally 9%)
It is responsible for the flash set but generates less heat. It has the poorest cementing value. Raising C 4 AF content reduces the strength slightly. The heat of hydration 420 J/g,
The rate of heat evolution of the principal compound if equal amount of each is considered will be in following descending order: C 3 A (865 J/g) > C 3 S (500 J/g) > C 4 AF (420 J/g) > C 2 S (260 J/g), Thus by increasing the C 2 S content the heat of hydration decreases, Note: The development of strength of the four principal compounds of cement with age: The rate of hydration is increased by an increase in the fineness of the cement. However total heat evolved is the same. The rate of hydration of the principal compounds is shown in the figure and will be in the following descending order: C 4 AF > C 3 A > C 3 S > C 2 S Important Points Hydration products of C 2 S are considered better than that of C 3 S. It is because of the lesser time formation of lime when C 2 S hydrates than those in hydration of C 3 S.2C 3 S + 6H → C 3 S 2 H 3 + 3 Ca(OH) 2 2C 2 S + 4H → C 3 S 2 H 3 + Ca(OH) 2 Last updated on Sep 22, 2022 The Chhattisgarh Public Service Commission (CGPSC) has activated the link to submit any objection against the CGPSC AE (Assistant Engineers) Provisional Answer Key.
What is soundness and unsoundness?
template.1 Validity and Invalidity, Soundness and Unsoundness The task of an argument is to provide statements (premises) that give evidence for the conclusion. There are two basic kinds of arguments. Deductive argument: involves the claim that the truth of its premises guarantees the truth of its conclusion; the terms valid and invalid are used to characterize deductive arguments.
A deductive argument succeeds when, if you accept the evidence as true (the premises), you must accept the conclusion. Inductive argument: involves the claim that the truth of its premises provides some grounds for its conclusion or makes the conclusion more probable; the terms valid and invalid cannot be applied.
Valid: an argument is valid if and only if it is necessary that if all of the premises are true, then the conclusion is true; if all the premises are true, then the conclusion must be true; it is impossible that all the premises are true and the conclusion is false.
- Invalid: an argument that is not valid.
- We can test for invalidity by assuming that all the premises are true and seeing whether it is still possible for the conclusion to be false.
- If this is possible, the argument is invalid.
- Validity and invalidity apply only to arguments, not statements.
- For our purposes, it is just nonsense to call a statement valid or invalid.
True and false apply only to statements, not arguments. For our purposes, it is just nonsense to call an argument true or false. All deductive arguments aspire to validity. If you consider the definitions of validity and invalidity carefully, you’ll note that valid arguments have the following important property: valid arguments preserve truth.
If all your premises are true and you make a valid argument from them, it must be the case that whatever conclusion you obtain is true. (We shall see below, however, that valid arguments do not necessarily preserve truth value: it is entirely possible to argue validly from false premises to a true conclusion).
Sound: an argument is sound if and only if it is valid and contains only true premises. Unsound: an argument that is not sound. Counterexample: an example which contradicts some statement or argument (ex. a counterexample to the statement “All fifteen year-olds have blue hair” would be a fifteen-year-old without blue hair); for an argument, a counterexample would be a situation in which the premises of the argument are true and the conclusion is false; counterexamples show statements to be false and arguments to be invalid.