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Concrete Cone Failure
Concrete cone is one of the failure modes of anchors in concrete, loaded by a tensile force. The failure is governed by crack growth in concrete, which forms a typical cone shape having the anchor's axis as revolution axis. Mechanical models ACI 349-85 Under tension loading, the concrete cone failure surface has 45° inclination. A constant distribution of tensile stresses is then assumed. The concrete cone failure load N_0 of a single anchor in uncracked concrete unaffected by edge influences or overlapping cones of neighboring anchors is given by: N_0 = f_ Where: f_ - tensile strength of concrete A_ - Cone's projected area Concrete capacity design (CCD) approach for fastening to concrete Under tension loading, the concrete capacity of a single anchor is calculated assuming an inclination between the failure surface and surface of the concrete member of about 35°. The concrete cone failure load N_0 of a single anchor in uncracked concrete unaffected by edge influ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Concrete Cone Model
Concrete is a composite material composed of fine and coarse construction aggregate, aggregate bonded together with a fluid cement (cement paste) that hardens (cures) over time. Concrete is the second-most-used substance in the world after water, and is the most widely used building material. Its usage worldwide, ton for ton, is twice that of steel, wood, plastics, and aluminum combined. Globally, the ready-mix concrete industry, the largest segment of the concrete market, is projected to exceed $600 billion in revenue by 2025. This widespread use results in a number of Environmental impact of concrete, environmental impacts. Most notably, the production process for cement produces large volumes of greenhouse gas emissions, leading to net 8% of global emissions. Other environmental concerns include widespread Sand theft, illegal sand mining, impacts on the surrounding environment such as increased surface runoff or Urban heat island, urban heat island effect, and potential publ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Concrete
Concrete is a composite material composed of fine and coarse aggregate bonded together with a fluid cement (cement paste) that hardens (cures) over time. Concrete is the second-most-used substance in the world after water, and is the most widely used building material. Its usage worldwide, ton for ton, is twice that of steel, wood, plastics, and aluminum combined. Globally, the ready-mix concrete industry, the largest segment of the concrete market, is projected to exceed $600 billion in revenue by 2025. This widespread use results in a number of environmental impacts. Most notably, the production process for cement produces large volumes of greenhouse gas emissions, leading to net 8% of global emissions. Other environmental concerns include widespread illegal sand mining, impacts on the surrounding environment such as increased surface runoff or urban heat island effect, and potential public health implications from toxic ingredients. Significant research and developmen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tension (physics)
In physics, tension is described as the pulling force transmitted axially by the means of a string, a rope, chain, or similar object, or by each end of a rod, truss member, or similar three-dimensional object; tension might also be described as the action-reaction pair of forces acting at each end of said elements. Tension could be the opposite of compression. At the atomic level, when atoms or molecules are pulled apart from each other and gain potential energy with a restoring force still existing, the restoring force might create what is also called tension. Each end of a string or rod under such tension could pull on the object it is attached to, in order to restore the string/rod to its relaxed length. Tension (as a transmitted force, as an action-reaction pair of forces, or as a restoring force) is measured in newtons in the International System of Units (or pounds-force in Imperial units). The ends of a string or other object transmitting tension will exert forces on the o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crack Spacing Of Reinforced Concrete
Concrete is a brittle material and can only withstand small amount of tensile strain due to stress before cracking. When a reinforced concrete member is put in tension, after cracking, the member elongates by widening of cracks and by formation of new cracks. Ignoring the small elastic strain in the concrete between the cracks, we can relate the crack width to the strain of the member by: :_= \epsilon_s_m Spacing of primary cracks Primary cracks (Figure 1) form when the tensile stress at the outer surface of the concrete reaches the tensile strength of concrete. When a primary crack forms, the concrete in the vicinity of the crack is relieved of any tension, resulting in a stress free zone near the crack. CEB-FIP code expressions for crack spacing and crack widths In the CEB-FIP Code the following expression is used to account for the average crack spacing: :s_m = 2(c + \frac) + k_1k_2\frac where :c = clear concrete cover :s = maximum spacing between longitudinal reinforc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rotation Around A Fixed Axis
Rotation around a fixed axis is a special case of rotational motion. The fixed- axis hypothesis excludes the possibility of an axis changing its orientation and cannot describe such phenomena as wobbling or precession. According to Euler's rotation theorem, simultaneous rotation along a number of stationary axes at the same time is impossible; if two rotations are forced at the same time, a new axis of rotation will appear. This article assumes that the rotation is also stable, such that no torque is required to keep it going. The kinematics and dynamics of rotation around a fixed axis of a rigid body are mathematically much simpler than those for free rotation of a rigid body; they are entirely analogous to those of linear motion along a single fixed direction, which is not true for ''free rotation of a rigid body''. The expressions for the kinetic energy of the object, and for the forces on the parts of the object, are also simpler for rotation around a fixed axis, th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Size Effect On Structural Strength
According to the classical theories of elasticity (physics), elastic or plasticity (physics), plastic structures made from a material with non-random strength of materials, strength (''f''t), the nominal strength (''σ''N) of a structure is independent of the structure size (''D'') when geometrically similar structures are considered.The nominal strength of a structure (''σ''N) has units of stress (mechanics), stress and is related to the maximum load (''P''max) that the structure can support. For structures that can be approximated as two-dimensional, ''σ''N = ''P''max/''bD'' where ''b'' is the thickness of the two-dimensional structure. For three-dimensional structures, ''σ''N = ''P''max/''D''2. Any structure dimension can be chosen for ''D'' but it must be wikt:homologous, homologous for every size. Any deviation from this property is called the size effect. For example, conventional strength of materials predicts that a large beam bending, beam and a tiny beam will fail at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Concrete Cone Group
Concrete is a composite material composed of fine and coarse aggregate bonded together with a fluid cement (cement paste) that hardens (cures) over time. Concrete is the second-most-used substance in the world after water, and is the most widely used building material. Its usage worldwide, ton for ton, is twice that of steel, wood, plastics, and aluminum combined. Globally, the ready-mix concrete industry, the largest segment of the concrete market, is projected to exceed $600 billion in revenue by 2025. This widespread use results in a number of environmental impacts. Most notably, the production process for cement produces large volumes of greenhouse gas emissions, leading to net 8% of global emissions. Other environmental concerns include widespread illegal sand mining, impacts on the surrounding environment such as increased surface runoff or urban heat island effect, and potential public health implications from toxic ingredients. Significant research and development is be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fracture Mechanics
Fracture mechanics is the field of mechanics concerned with the study of the propagation of cracks in materials. It uses methods of analytical solid mechanics to calculate the driving force on a crack and those of experimental solid mechanics to characterize the material's resistance to fracture. Theoretically, the stress ahead of a sharp crack tip becomes infinite and cannot be used to describe the state around a crack. Fracture mechanics is used to characterise the loads on a crack, typically using a single parameter to describe the complete loading state at the crack tip. A number of different parameters have been developed. When the plastic zone at the tip of the crack is small relative to the crack length the stress state at the crack tip is the result of elastic forces within the material and is termed linear elastic fracture mechanics (LEFM) and can be characterised using the stress intensity factor K. Although the load on a crack can be arbitrary, in 1957 G. Irwin f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Concrete Fracture Analysis
Fracture mechanics is the field of mechanics concerned with the study of the propagation of cracks in materials. It uses methods of analytical solid mechanics to calculate the driving force on a crack and those of experimental solid mechanics to characterize the material's resistance to fracture. Theoretically, the stress ahead of a sharp crack tip becomes infinite and cannot be used to describe the state around a crack. Fracture mechanics is used to characterise the loads on a crack, typically using a single parameter to describe the complete loading state at the crack tip. A number of different parameters have been developed. When the plastic zone at the tip of the crack is small relative to the crack length the stress state at the crack tip is the result of elastic forces within the material and is termed linear elastic fracture mechanics (LEFM) and can be characterised using the stress intensity factor K. Although the load on a crack can be arbitrary, in 1957 G. Irwin foun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Size Effect
According to the classical theories of elastic or plastic structures made from a material with non-random strength (''f''t), the nominal strength (''σ''N) of a structure is independent of the structure size (''D'') when geometrically similar structures are considered.The nominal strength of a structure (''σ''N) has units of stress and is related to the maximum load (''P''max) that the structure can support. For structures that can be approximated as two-dimensional, ''σ''N = ''P''max/''bD'' where ''b'' is the thickness of the two-dimensional structure. For three-dimensional structures, ''σ''N = ''P''max/''D''2. Any structure dimension can be chosen for ''D'' but it must be homologous for every size. Any deviation from this property is called the size effect. For example, conventional strength of materials predicts that a large beam and a tiny beam will fail at the same stress if they are made of the same material. In the real world, because of size effects, a larger beam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Structural Connectors
A structure is an arrangement and organization of interrelated elements in a material object or system, or the object or system so organized. Material structures include man-made objects such as buildings and machines and natural objects such as biological organisms, minerals and chemicals. Abstract structures include data structures in computer science and musical form. Types of structure include a hierarchy (a cascade of one-to-many relationships), a network featuring many-to-many links, or a lattice featuring connections between components that are neighbors in space. Load-bearing Buildings, aircraft, skeletons, anthills, beaver dams, bridges and salt domes are all examples of load-bearing structures. The results of construction are divided into buildings and non-building structures, and make up the infrastructure of a human society. Built structures are broadly divided by their varying design approaches and standards, into categories including building structures, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wall Anchors
A wall is a structure and a surface that defines an area; carries a load; provides security, shelter, or soundproofing; or, is decorative. There are many kinds of walls, including: * Walls in buildings that form a fundamental part of the superstructure or separate interior rooms, sometimes for fire safety *Glass walls (a wall in which the primary structure is made of glass; does not include openings within walls that have glass coverings: these are windows) * Border barriers between countries * Brick walls * Defensive walls in fortifications * Permanent, solid fences * Retaining walls, which hold back dirt, stone, water, or noise sound * Stone walls * Walls that protect from oceans ( seawalls) or rivers (levees) Etymology The term ''wall'' comes from Latin ''vallum'' meaning "...an earthen wall or rampart set with palisades, a row or line of stakes, a wall, a rampart, fortification..." while the Latin word ''murus'' means a defensive stone wall. English uses the same wor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
