If high-performance steel or mild steel reinforcement was designed as a road?
On high-performance steel is the preferred material for the strengthening of concrete pavement for the following reasons:
(I) The main aim of reinforcing steel in concrete is to control cracking. If mild steel is adopted for the reinforcement, initiation of cracking of mild steel becomes overloaded and
will be exposed. High Yield Steel provides the resistance to crack growth. The situation described above is a general with an abnormal load of cement on the road over the limits of design.
(II), high-performance steel is less prone to deformation and bending during routine operations management.
(Iii) In today's market, the steel mesh reinforcement is normally high-performance steel and use steel as reinforcement of the route requires the award of special orders from suppliers.
Analysis and design of the tubular structure 2-D modeling with USFOS
USFOS is the analysis tool to predict both the strength of structures subjected to accidental loads and the residual strength of damaged structures after such charges. It is based on a finite element model. USFOS encompasses the static analysis of the fall, the nonlinear analysis of time series and dynamic analysis of the eigenvalues in general, jackets, accessories, jack-up, and floats. With the main purpose of this paper is to analyze two types of offshore structures in 2-D and study the mechanism of progressive collapse of these two fields, due to different combinations of loads in the X and Y axis First the boundary conditions were established for the vertical elements, using modeling and USFOS were tested to collapse under the burden of four possible combinations. Behavioral differences of the two frameworks have been studied and brace-chord sizes have been fixed.
This type of analysis is useful for testing if a jacket sea with some specified size can tolerate the stress that comes to her from the waves, wind or the effects of ships. Using the built-in redundancy in most offshore structures progressive collapse limit state can be used to design accidental injury or extreme loads. In conjunction with the traditional elastic load-shifting is generally not considered. Reduce or plastic design limit states, it is possible to local failure of performance or buckling, and even the partial collapse if the overall integrity of the structure preserved. In short, the designers of plastic limit state design to take advantage of any spare capacity in the structure.
Behavioral studies Hollow double wall steel composite concrete columns This document includes the experimental study of eight concrete filled double skin steel tubular (DSCFT) beam columns placed concentric circular section filled with self-compacting concrete. Tests on the samples was done by applying eccentric loads. The main experimental parameters of beam-columns, slenderness and eccentricity of the load. Test samples studied the behavior of the deviation of the load, the effect of confinement, and the strength of the columns. Experimental observations have shown for the stress-strain curves. Characteristics such as strength, stiffness, ductility and failure are discussed. Predicted load vs deformation relationships are in good agreement with the results of beam-column tests. Columns filled with SCC of DSCFT showed good strength and ductility. The changes are proposed equations to find the maximum compressive strength of the columns filled with SCC DSCFT.
What is the purpose of strengthening the skin depth of the bar?
In BS8110 states that secondary reinforcement should be provided for exceeding 750 deep beams at a distance measured depth 2 / 3 of the face in tension. Experimental work has shown that less or about half the depth of deep beams, the maximum width of cracks caused by bending can be two to three times greater than the width of the crack, even on the surface where the origin of the crack forms.
The presence of cracks is not desirable from an aesthetic point of view. It also raises potential problems of corrosion of reinforcing deep beams. To guard against cracking of the building has been designed on the sides of deep beams to limit the formation of wide cracks in bending. Although the main function of enhancing the skin is the crack width control can be used to provide resistance to bending of the section.
What is the difference between performance of concrete bonding between epoxy and galvanized bars?
Based on the findings of the Board 211 ads, the union of galvanized bars in concrete is lower due to early for the release of hydrogen when the zinc reacts with calcium hydroxide in the concrete and the presence of hydrogen tends to reduce the strength of the bond between galvanized bars and concrete. However, the union will increase over time until the full bond strength of galvanized bars is not reached.
Epoxy-coated bars are bond strength of 20% below the bar at the bottom of the concrete components while bars on top of it there is not much difference compared to the uncoated side bars.
What kind of reinforcing bar corrosion resistant, epoxy-coated bars, stainless steel or galvanized rods?
Based on the experience carried out by the Building Research Establishment, it was shown that the corrosion resistance of galvanized steel, were the worst among the three types of reinforcement bar. For galvanized steel rods began to corrosion occurs when a certain chloride content in concrete (equivalent to 0.4% by weight of cement) was exceeded. But for the epoxy bars, extended the time it takes to cracks that occur when comparing with galvanized steel bars.
The best stainless steel reinforcement corrosion resistant all. Specifically, the austenitic stainless steel has remained non-corrosive, even chlorine contamination occurred in the concrete experience. Reference is made to KWJ Treadaway (1988).
Tie reinforcement son next to and above Class F4 and F5 finishes shall be stainless steel. Why?
If the son of plain steel fasteners are used for reinforcement adjacent to the class F4 and F5 are finished, raise the issue with rust stains which can degrade the appearance of exposed surfaces of concrete. The rate of corrosion of mild steel son home correspond to normal steel reinforcement. But to tie the son with very small diameter, after long exposure he has a good chance of completely rust and the rust will stain the formwork and significantly affect the finishing of concrete. Therefore, the stainless steel wire tie to specified locations in the vicinity of high-quality finish to prevent rust stains from corroded son writing.
Note: Tie the wires are wires used for connecting and strengthening of steel reinforcement bars.
If the ordinary steel tie wires are used to confirm the F4 and F5 the next class to run out, will cause problems with rust stains, which can alter the appearance of exposed concrete surfaces. Amount of corrosion of ordinary steel tie wire is similar to that of normal steel reinforcement. However, tying the threads of a very small diameter, while a long exposure, is a great opportunity to completely rust and rust stains, mold and these significantly affect the concrete surface. Therefore, stainless steel wire binding posts are set in the vicinity of a high quality finish to avoid rust staining typing corroded cables.
Note: The son of this type is the child for fixing and connecting the reinforcing steel bars.
What is the effect of corrosion on steel frames?
Corrosion of rebar in a concrete structure is undesirable in the following ways:
(I) the presence of rust weakens the bond strength of d'armature because corrosion occurs in the ribs raised and bridges the gap between the ribs, the smoothing of the original shape distorted. In strains of the essence of the relationship between concrete and deformed bars of the mechanical lock between the ribs raised and concrete. The reduction of the mechanical blocking of corrosion resulting from the decrease in bond strength with concrete.
(Ii) the presence of corrosion reduces the effective cross-sectional area of reinforcement. Therefore, the ability of available traction force of the reinforcement was reduced by a significant reduction in the surface of the section.
(Iii) corrosion products occupy about three times the initial volume of the steel from which it is formed. These drastic increase in the volume generates significant forces defects near the reinforcement. Therefore, cracks are formed along the reinforcement when the tensile strength of concrete is exceeded.
Column reinforcement, why sometimes designed helical reinforcement instead of normal links?
Use of links to the design of columns in Britain is very popular. But American engineers tend to use stronger links rather normal helical spiral reinforcement due to a potential benefit to protect the columns / cells against seismic loads. Moreover, when the graph drops non-state crack-free concrete and hoop first, followed by any failure of all columns. Concrete cylindrical shells without reinforcement gives a warning before the sudden failure of columns as suggested by GP Manning (1924). In addition, it can take up to a higher workload than usual link reinforcement.
For example, helical reinforcement is taken in the design of batteries thrown overboard by the government.
Note: helical reinforcement concerns the reinforcement is cut in a spiral.
On high-performance steel is the preferred material for the strengthening of concrete pavement for the following reasons:
(I) The main aim of reinforcing steel in concrete is to control cracking. If mild steel is adopted for the reinforcement, initiation of cracking of mild steel becomes overloaded and
will be exposed. High Yield Steel provides the resistance to crack growth. The situation described above is a general with an abnormal load of cement on the road over the limits of design.
(II), high-performance steel is less prone to deformation and bending during routine operations management.
(Iii) In today's market, the steel mesh reinforcement is normally high-performance steel and use steel as reinforcement of the route requires the award of special orders from suppliers.
Analysis and design of the tubular structure 2-D modeling with USFOS
USFOS is the analysis tool to predict both the strength of structures subjected to accidental loads and the residual strength of damaged structures after such charges. It is based on a finite element model. USFOS encompasses the static analysis of the fall, the nonlinear analysis of time series and dynamic analysis of the eigenvalues in general, jackets, accessories, jack-up, and floats. With the main purpose of this paper is to analyze two types of offshore structures in 2-D and study the mechanism of progressive collapse of these two fields, due to different combinations of loads in the X and Y axis First the boundary conditions were established for the vertical elements, using modeling and USFOS were tested to collapse under the burden of four possible combinations. Behavioral differences of the two frameworks have been studied and brace-chord sizes have been fixed.
This type of analysis is useful for testing if a jacket sea with some specified size can tolerate the stress that comes to her from the waves, wind or the effects of ships. Using the built-in redundancy in most offshore structures progressive collapse limit state can be used to design accidental injury or extreme loads. In conjunction with the traditional elastic load-shifting is generally not considered. Reduce or plastic design limit states, it is possible to local failure of performance or buckling, and even the partial collapse if the overall integrity of the structure preserved. In short, the designers of plastic limit state design to take advantage of any spare capacity in the structure.
Behavioral studies Hollow double wall steel composite concrete columns This document includes the experimental study of eight concrete filled double skin steel tubular (DSCFT) beam columns placed concentric circular section filled with self-compacting concrete. Tests on the samples was done by applying eccentric loads. The main experimental parameters of beam-columns, slenderness and eccentricity of the load. Test samples studied the behavior of the deviation of the load, the effect of confinement, and the strength of the columns. Experimental observations have shown for the stress-strain curves. Characteristics such as strength, stiffness, ductility and failure are discussed. Predicted load vs deformation relationships are in good agreement with the results of beam-column tests. Columns filled with SCC of DSCFT showed good strength and ductility. The changes are proposed equations to find the maximum compressive strength of the columns filled with SCC DSCFT.
What is the purpose of strengthening the skin depth of the bar?
In BS8110 states that secondary reinforcement should be provided for exceeding 750 deep beams at a distance measured depth 2 / 3 of the face in tension. Experimental work has shown that less or about half the depth of deep beams, the maximum width of cracks caused by bending can be two to three times greater than the width of the crack, even on the surface where the origin of the crack forms.
The presence of cracks is not desirable from an aesthetic point of view. It also raises potential problems of corrosion of reinforcing deep beams. To guard against cracking of the building has been designed on the sides of deep beams to limit the formation of wide cracks in bending. Although the main function of enhancing the skin is the crack width control can be used to provide resistance to bending of the section.
What is the difference between performance of concrete bonding between epoxy and galvanized bars?
Based on the findings of the Board 211 ads, the union of galvanized bars in concrete is lower due to early for the release of hydrogen when the zinc reacts with calcium hydroxide in the concrete and the presence of hydrogen tends to reduce the strength of the bond between galvanized bars and concrete. However, the union will increase over time until the full bond strength of galvanized bars is not reached.
Epoxy-coated bars are bond strength of 20% below the bar at the bottom of the concrete components while bars on top of it there is not much difference compared to the uncoated side bars.
What kind of reinforcing bar corrosion resistant, epoxy-coated bars, stainless steel or galvanized rods?
Based on the experience carried out by the Building Research Establishment, it was shown that the corrosion resistance of galvanized steel, were the worst among the three types of reinforcement bar. For galvanized steel rods began to corrosion occurs when a certain chloride content in concrete (equivalent to 0.4% by weight of cement) was exceeded. But for the epoxy bars, extended the time it takes to cracks that occur when comparing with galvanized steel bars.
The best stainless steel reinforcement corrosion resistant all. Specifically, the austenitic stainless steel has remained non-corrosive, even chlorine contamination occurred in the concrete experience. Reference is made to KWJ Treadaway (1988).
Tie reinforcement son next to and above Class F4 and F5 finishes shall be stainless steel. Why?
If the son of plain steel fasteners are used for reinforcement adjacent to the class F4 and F5 are finished, raise the issue with rust stains which can degrade the appearance of exposed surfaces of concrete. The rate of corrosion of mild steel son home correspond to normal steel reinforcement. But to tie the son with very small diameter, after long exposure he has a good chance of completely rust and the rust will stain the formwork and significantly affect the finishing of concrete. Therefore, the stainless steel wire tie to specified locations in the vicinity of high-quality finish to prevent rust stains from corroded son writing.
Note: Tie the wires are wires used for connecting and strengthening of steel reinforcement bars.
If the ordinary steel tie wires are used to confirm the F4 and F5 the next class to run out, will cause problems with rust stains, which can alter the appearance of exposed concrete surfaces. Amount of corrosion of ordinary steel tie wire is similar to that of normal steel reinforcement. However, tying the threads of a very small diameter, while a long exposure, is a great opportunity to completely rust and rust stains, mold and these significantly affect the concrete surface. Therefore, stainless steel wire binding posts are set in the vicinity of a high quality finish to avoid rust staining typing corroded cables.
Note: The son of this type is the child for fixing and connecting the reinforcing steel bars.
What is the effect of corrosion on steel frames?
Corrosion of rebar in a concrete structure is undesirable in the following ways:
(I) the presence of rust weakens the bond strength of d'armature because corrosion occurs in the ribs raised and bridges the gap between the ribs, the smoothing of the original shape distorted. In strains of the essence of the relationship between concrete and deformed bars of the mechanical lock between the ribs raised and concrete. The reduction of the mechanical blocking of corrosion resulting from the decrease in bond strength with concrete.
(Ii) the presence of corrosion reduces the effective cross-sectional area of reinforcement. Therefore, the ability of available traction force of the reinforcement was reduced by a significant reduction in the surface of the section.
(Iii) corrosion products occupy about three times the initial volume of the steel from which it is formed. These drastic increase in the volume generates significant forces defects near the reinforcement. Therefore, cracks are formed along the reinforcement when the tensile strength of concrete is exceeded.
Column reinforcement, why sometimes designed helical reinforcement instead of normal links?
Use of links to the design of columns in Britain is very popular. But American engineers tend to use stronger links rather normal helical spiral reinforcement due to a potential benefit to protect the columns / cells against seismic loads. Moreover, when the graph drops non-state crack-free concrete and hoop first, followed by any failure of all columns. Concrete cylindrical shells without reinforcement gives a warning before the sudden failure of columns as suggested by GP Manning (1924). In addition, it can take up to a higher workload than usual link reinforcement.
For example, helical reinforcement is taken in the design of batteries thrown overboard by the government.
Note: helical reinforcement concerns the reinforcement is cut in a spiral.
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