Synonyms containing breaking strain
We've found 1,941 synonyms:
|strains upon ordnance|
strains upon ordnance
The exterior form of cannon is determined by the variable thickness of the metal which surrounds the bore at different points of its length. In general terms, the thickness is greatest at the seat of the charge, and least at or near the muzzle. This arrangement is made on account of the variable action of the powder and projectile along the bore, and the necessity of disposing the metal in the safest and most economical manner. The pressure at different points may be approximately determined by calculation, or, more accurately, by experiment. In the latter method, the plan generally employed consists in boring a series of small holes through the side of a gun at right angles to its axis at known distances apart. A steel ball is projected from each hole in succession into a target, or ballistic pendulum, by the force of the charge acting through it, and the pressure at the various points is deduced from the velocities communicated to these balls. This method was adopted by Col. Bomford. Instead of the projectile a steel punch may be employed, which is pressed by the force of the charge into a piece of soft copper. (See Pressure-gauge.) The weight necessary to make an equal indentation in the same piece is then ascertained by a testing machine. The strains to which all fire-arms are subjected may be classified as follows: (1) The tangential strain which tends to split the piece open longitudinally, and is similar in its action to the force which bursts the hoops of a barrel. (2) The longitudinal strain which acts to pull the piece apart in the direction of its length. Its action is greatest at or near the bottom of the bore, and least at the muzzle, where it is nothing; these two strains increase the volume of the metal to which they are applied. (3) A strain of compression which acts from the axis outward to crush the truncated wedges of which a unit of length of the piece may be supposed to consist; this strain compresses the metal and enlarges the bore. (4) A transverse strain which acts to break transversely by bending outward the staves of which the piece may be supposed to consist. This strain compresses the metal on the inner and extends it on the outer surface. It is known that rupture will take place due to the tangential strain alone, when three times the pressure upon a unit of surface of the bore is greater than twice the tensile strength. Due to the longitudinal strain alone, rupture will take place in the direction of the length, when the pressure is greater than twice the tensile strength; and if the transverse strain alone is considered, rupture will take place when twice the pressure is greater than three times the tensile strength. It therefore appears that the tendency to rupture is greater from the action of the tangential force than from any other, and for lengths above two, or perhaps three calibers, the tangential resistance may be said to act alone, as the aid derived from the transverse resistance will be but trifling for greater lengths of bore; but for lengths of bore less than two calibers, this resistance will be aided by both the transverse and the longitudinal resistance. Every piece should therefore have sufficient thickness of breech to prevent splitting through the latter; after this point has been attained, any additional thickness of breech adds nothing to the strength of the piece. It therefore appears that a fire-arm is strongest at or near the bottom of the bore, and that its strength is diminished rapidly as the length of the bore increases to a certain point (probably not more than three calibers from the bottom); after which, for equal thickness of metal, its strength becomes sensibly uniform. The metals of which cannon are made being crystalline in structure, the size and arrangement of the crystals have an important influence on its strength to resist a particular force; and a metal will have the greatest strength with reference to a particular force when its crystals are small, and the principal faces are parallel to the straining force, if it be one of extension, and perpendicular to it, if it be one of compression. The position of the principal crystalline faces of a cooling solid is found to be perpendicular to the cooling surface; the result of this arrangement of crystals is to create planes of weakness where the different systems of crystals intersect. The effect of this law upon cannons, it has been discovered, is to render radial specimens more tenacious than those cut tangentially from the same gun. The manner and rapidity of cooling have also a great effect upon the ability of cannon to resist strains, and as all solid bodies contract their size in the operation of cooling, it follows that if the different parts of a cannon cool unequally, it will change its form, provided it be not restrained by the presence of a superior force. If it be so restrained, the contractile force will diminish the adhesion of the parts by an amount which depends on the rate of
— Military Dictionary and Gazetteer
Breaking is a martial arts technique that is used in competition, demonstration and testing. Breaking is an action where a martial artist uses a striking surface to break one or more objects using the skills honed in their art form. The striking surface is usually a hand or a foot, but may also be a fingertip, toe, head, elbow, knuckle, or knee. The most common object is a piece of wood, though it is also common to break bricks or cinder blocks. Breaking can be often seen in karate, taekwondo and pencak silat, Spetsnaz are also known for board, and brick breaking, but not all styles of martial arts place equal emphasis on, or use, breaking. In styles where striking and kicking is less important and there is an emphasis on grappling or weaponry, breaking is less prominent. Traditional Japanese martial art schools place little, if any, emphasis on board-breaking, although the art of breaking objects was known as tameshiwari, while the similar practice of Tameshigiri or 'test cutting' is used in sword arts. Breaking is based on physics and selection of materials, and the most commonly seen breaking involves spaced, softwood boards. While very difficult to break even a piece of soft pine wood hitting against the grain, breaking is almost always done with the grain - which requires little skill or strength. The use of spacers means instead of breaking the entire stack at once, they break one at a time; each one helps break the next as little momentum is lost and gravity is helping. Because of this, breaking is primarily used as an advertising gimmick to woo potential customers.
In a molecule, strain energy is released when the constituent atoms are allowed to rearrange themselves in a chemical reaction or a change of chemical conformation in a way that: ⁕angle strain, ⁕torsional strain, ⁕ring strain and/or steric strain, ⁕Allylic strain, and ⁕pentane interference are reduced. The external work done on an elastic member in causing it to distort from its unstressed state is transformed into strain energy which is a form of potential energy. The strain energy in the form of elastic deformation is mostly recoverable in the form of mechanical work. For example, the heat of combustion of cyclopropane is higher than that of propane for each additional CH2 unit. Compounds with unusually large strain energy include tetrahedranes, propellanes, cubanes, fenestranes and cyclophanes.
Shearing in continuum mechanics refers to the occurrence of a shear strain, which is a deformation of a material substance in which parallel internal surfaces slide past one another. It is induced by a shear stress in the material. Shear strain is distinguished from volumetric strain, the change in a material's volume in response to stress. Often, the verb shearing refers more specifically to a mechanical process that causes a plastic shear strain in a material, rather than causing a merely elastic one. A plastic shear strain is a continuous deformation that is irreversible, such that the material does not recover its original shape. It occurs when the material is yielding. The process of shearing a material may induce a volumetric strain along with the shear strain. In soil mechanics, the volumetric strain associated with shearing is known as Reynolds' dilation if it increases the volume, or compaction if it decreases the volume. The shear center is an imaginary point on a section, where a shear force can be applied without inducing any torsion. In general, the shear center is not the centroid. For cross-sectional areas having one axis of symmetry, the shear center is located on the axis of symmetry. For those having two axes of symmetry, the shear center lies on the centroid of the cross-section.
In baseball, a breaking ball is a pitch that does not travel straight like a fastball as it approaches the batter. A pitcher who uses primarily breaking ball pitches is often referred to as a junkballer. A breaking ball will have some sideways or downward motion on it. Curveballs and sliders are two types of breaking balls. A breaking ball is more difficult than a fastball for a catcher to receive as breaking pitches sometimes hit the ground before making it to the plate. The pitcher must therefore have confidence in the catcher, and the catcher have confidence in himself, to block a ball in the dirt when there are runners on base, since if the ball gets away from the catcher the runners will likely advance. If a breaking ball fails to break, it is called a 'hanging' breaking ball. The "hanger" becomes a high, slow pitch that is very easy to hit, and often results in hits for extra bases or a home run. A curveball does not curve side to side, but it rather drops when it reaches the strike zone. Whether a right-handed or a left-handed pitcher is throwing will dictate which direction a catcher will turn his body to adjust for the spin of a breaking ball. Therefore, blocking the breaking ball requires some thought and preparation.
The neutral axis is an axis in the cross section of a beam or shaft along which there are no longitudinal stresses or strains. If the section is symmetric, isotropic and is not curved before a bend occurs, then the neutral axis is at the geometric centroid. All fibers on one side of the neutral axis are in a state of tension, while those on the opposite side are in compression Since the beam is undergoing uniform bending, a plane on the beam remains plane. That is: Where is the shear strain and is the shear stress There is a compressive strain at the top of the beam, and a tensile strain at the bottom of the beam. Therefore by the Intermediate Value Theorem, there must be some point in between the top and the bottom that has no strain, since the strain in a beam is a continuous function. Let L be the original length of the beam ε is the strain as a function of coordinate on the face of the beam. σ is the stress as a function of coordinate on the face of the beam. ρ is the radius of curvature of the beam at its neutral axis. θ is the bend angle Since the bending is uniform and pure, there is therefore at a distance y from the neutral axis with the inherent property of having no strain:
strān, v.t. to stretch tight: to draw with force: to exert to the utmost: to injure by overtasking: to make tight: to constrain, make uneasy or unnatural: to press to one's self, to embrace: to pass through a filter.—v.i. to make violent efforts: to filter.—n. the act of straining: a violent effort: an injury inflicted by straining, esp. a wrenching of the muscles: a note, sound, or song, stretch of imagination, &c.: any change of form or bulk of a portion of matter either solid or fluid, the system of forces which sustains the strain being called the stress: mood, disposition.—ns. Strain′er, one who, or that which, strains: an instrument for filtration: a sieve, colander, &c.; Strain′ing, a piece of leather for stretching as a base for the seat of a saddle.—Strain a point, to make a special effort: to exceed one's duty; Strain at, in Matt. xxiii. 24, a misprint for Strain out. [O. Fr. straindre—L. stringĕre, to stretch tight. Cf. String and Strong.]
— Chambers 20th Century Dictionary
In physics, symmetry breaking is a phenomenon in which (infinitesimally) small fluctuations acting on a system crossing a critical point decide the system's fate, by determining which branch of a bifurcation is taken. To an outside observer unaware of the fluctuations (or "noise"), the choice will appear arbitrary. This process is called symmetry "breaking", because such transitions usually bring the system from a symmetric but disorderly state into one or more definite states. Symmetry breaking is thought to play a major role in pattern formation. In 1972, Nobel laureate P.W. Anderson used the idea of symmetry breaking to show some of the drawbacks of reductionism in his paper titled "More is different" in Science.Symmetry breaking can be distinguished into two types, explicit symmetry breaking and spontaneous symmetry breaking, characterized by whether the equations of motion fail to be invariant or the ground state fails to be invariant.
In fluid dynamics, a breaking wave is a wave whose amplitude reaches a critical level at which some process can suddenly start to occur that causes large amounts of wave energy to be transformed into turbulent kinetic energy. At this point, simple physical models that describe wave dynamics often become invalid, particularly those that assume linear behaviour. The most generally familiar sort of breaking wave is the breaking of water surface waves on a coastline. Wave breaking generally occurs where the amplitude reaches the point that the crest of the wave actually overturns—the types of breaking water surface waves are discussed in more detail below. Certain other effects in fluid dynamics have also been termed "breaking waves," partly by analogy with water surface waves. In meteorology, atmospheric gravity waves are said to break when the wave produces regions where the potential temperature decreases with height, leading to energy dissipation through convective instability; likewise Rossby waves are said to break when the potential vorticity gradient is overturned. Wave breaking also occurs in plasmas, when the particle velocities exceed the wave's phase speed.
Eye strain, also known as asthenopia (from Greek asthen-opia, Ancient Greek: ἀσθεν-ωπία, transl. weak-eye-condition), is an eye condition that manifests through non-specific symptoms such as fatigue, pain in or around the eyes, blurred vision, headache, and occasional double vision. Symptoms often occur after long-term use of computers, digital devices, reading, driving long distances or other activities that involve extended visual tasks.When concentrating on a visually intense task, such as continuously focusing on a book or computer monitor, the ciliary muscles and the extraocular muscles are strained. This causes discomfort, soreness or pain on the eyeballs. Closing the eyes for ten minutes and relaxing the muscles of the face and neck at least once an hour usually alleviates the problem. It is more important to ensure seven to eight hours of uninterrupted sleep every night to allow the tissues to heal. A CRT (cathode ray tube) computer monitor with a low refresh rate (<70 Hz) or a CRT television can cause similar problems because the image has a visible flicker. Even if this flicker is imperceptible, it can still contribute to eye strain and fatigue. Aging CRTs also often go slightly out of focus, and this can cause eye strain. Old tube-style monitors can be replaced with a flat-panel LCD (liquid crystal display) like those on laptop computers. LCD screens are easier on the eyes and usually have an anti-reflective surface.A page or photograph with the same image twice, but slightly displaced (from a printing mishap, a camera moving during the shot, etc.) can cause eye strain due to the brain misinterpreting the image fault as diplopia and trying in vain to adjust the sideways movements of the two eyeballs to fuse the two images into one. Eye strain can also happen when viewing a blurred image (including images deliberately partly blurred for censorship), due to the ciliary muscle tightening trying in vain to focus the blurring out. Subtle blurring is also induced by the poor refractive properties of plastic and polycarbonate lenses. Glass lenses are known to offer better visual acuity.
Strain rate is the rate of change in strain of a material with respect to time. The strain rate at some point within the material measures the rate at which the distances of adjacent parcels of the material change with time in the neighborhood of that point. It comprises both the rate at which the material is expanding or shrinking, and also the rate at which it is being deformed by progressive shearing without changing its volume. It is zero if these distances do not change, as happens when all particles in some region are moving with the same velocity and/or rotating with the same angular velocity, as if that part of the medium were a rigid body. The strain rate is a concept of materials science and continuum mechanics, that plays an essential role in the physics of fluids and deformable solids. In an isotropic Newtonian fluid, in particular, the viscous stress is a linear function of the rate of strain, defined by two coefficients, one relating to the expansion rate and one relating to the shear rate.
|Strain energy density function|
Strain energy density function
A strain energy density function or stored energy density function is a scalar valued function that relates the strain energy density of a material to the deformation gradient. Equivalently, where is the deformation gradient tensor, is the right Cauchy-Green deformation tensor, is the left Cauchy-Green deformation tensor, and is the rotation tensor from the polar decomposition of . For an anisotropic material, the strain energy density function depends implicitly on reference vectors or tensors that characterize internal material texture. The spatial representation, must further depend explicitly on the polar rotation tensor to provide sufficient information to convect the reference texture vectors or tensors into the spatial configuration. For an isotropic material, consideration of the principle of material frame indifference leads to the conclusion that the strain energy density function depends only on the invariants of . In other words, the strain energy density function can be expressed uniquely in terms of the principal stretches or in terms of the invariants of the left Cauchy-Green deformation tensor or right Cauchy-Green deformation tensor and we have:
brāk, v.t. to part by force: to shatter: to crush: to tame, or wear out: to violate, or outrage, as a law, a bargain, &c.: to check by intercepting, as a fall: to interrupt, as silence, or the monotony of anything, or in 'to break one off a habit:' to make bankrupt: to degrade from rank, as an officer.—v.i. to part in two: to burst forth: to open or appear, as the morning: to become bankrupt: to crack or give way, as the voice: to dissolve, as frost: to collapse in foam, as a wave: to fall out, as with a friend:—pa.t. brōke; pa.p. brōk′en.—n. the state of being broken: an opening: a pause or interruption: (billiards) a consecutive series of successful strokes, also the number of points attained by such: the dawn.—ns. Break′age, the action of breaking, or its consequences: an interruption; Break′-down, a dance, vigorous rather than graceful, in which much noise is made by the feet of the one performer; Break′er, a wave broken on rocks or the shore.—adj. Break′-neck, likely to cause a broken neck.—ns. Break′-prom′ise, Break′-vow, one who makes a practice of breaking his promise or vow; Break′water, a barrier to break the force of the waves.—Break a jest, to utter a jest unexpectedly; Break a lance with, to enter into a contest with a rival; Break away, to go away abruptly, as from prison, &c.: to be scattered, as clouds after a storm; Break bulk, to open the hold and take out a portion of the cargo; Break cover, to burst forth from concealment, as a fox; Break down, to crush down or level: to collapse, to fail completely; Break forth, to burst out, issue; Break ground, to commence digging or excavation: to begin; Break in, to train to labour, as a horse; Break in, in upon, or into, to enter violently or unexpectedly, to interpose abruptly in a conversation, &c.; Break loose, to extricate one's self forcibly: to break through all restraint; Break news, to make anything known, esp. of bad news, with caution and delicacy; Break off, to separate by breaking, put an end to; Break out, to appear suddenly: to break through all restraint; Break sheer (said of a ship riding at anchor), to be forced by wind or tide out of a position clear of the anchor; Break the heart, to destroy with grief; Break the ice (fig.), to get through first difficulties: Break up, to break open; Break upon the wheel, to punish by stretching a criminal on a wheel and breaking his bones; Break wind, to void wind from the stomach; Break with, to fail out, as friends may do. [A.S. brecan; Ger. brechen.]
— Chambers 20th Century Dictionary
A strain gauge is a device used to measure the strain of an object. Invented by Edward E. Simmons and Arthur C. Ruge in 1938, the most common type of strain gauge consists of an insulating flexible backing which supports a metallic foil pattern. The gauge is attached to the object by a suitable adhesive, such as cyanoacrylate. As the object is deformed, the foil is deformed, causing its electrical resistance to change. This resistance change, usually measured using a Wheatstone bridge, is related to the strain by the quantity known as the gauge factor.
Young's modulus, also known as the tensile modulus or elastic modulus, is a measure of the stiffness of an elastic material and is a quantity used to characterize materials. It is defined as the ratio of the stress along an axis over the strain along that axis in the range of stress in which Hooke's law holds. In solid mechanics, the slope of the stress-strain curve at any point is called the tangent modulus. The tangent modulus of the initial, linear portion of a stress-strain curve is called Young's modulus. It can be experimentally determined from the slope of a stress-strain curve created during tensile tests conducted on a sample of the material. In anisotropic materials, Young's modulus may have different values depending on the direction of the applied force with respect to the material's structure. Young's modulus is the most common elastic modulus, sometimes called the modulus of elasticity, but there are other elastic moduli measured, too, such as the bulk modulus and the shear modulus. It is named after Thomas Young, the 19th century British scientist. However, the concept was developed in 1727 by Leonhard Euler, and the first experiments that used the concept of Young's modulus in its current form were performed by the Italian scientist Giordano Riccati in 1782, predating Young's work by 25 years.