CN105550418B - CFRP plate reinforces the calculation method for setting the Ultimate flexural strength of core beam - Google Patents
CFRP plate reinforces the calculation method for setting the Ultimate flexural strength of core beam Download PDFInfo
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Abstract
The calculation method for setting the Ultimate flexural strength of core beam is reinforced the invention proposes a kind of CFRP plate, belongs to beam reinforcement technique field.The calculation method is the following steps are included: (1) does basic assumption to reinforcing process；(2) it calculates under each material damage situation, the stress-strain relation of the cross section of core material；(3) it calculates under each material damage situation, the height of the compressive region of the cross section of core material；(4) it calculates under each material damage situation, the height of the plasticity of the compressive region of the cross section of core material；(5) according to the height of the plasticity of the height and compressive region of the compressive region of the cross section of core material under each material damage situation, the flexure bearing capacity reinforced under corresponding each material damage situation and set core beam is calculated, the Ultimate flexural strength for reinforcing the considerations of setting core beam plasticity is obtained.The present invention can effectively calculate the Ultimate flexural strength that CFRP plate reinforces the considerations of setting core beam plasticity, and strong theoretical direction is provided for engineer application.
Description
Technical Field
The invention belongs to the technical field of beam reinforcement, and relates to a method for calculating ultimate bearing capacity, in particular to a method for calculating ultimate bearing capacity of a reinforced core beam.
Background
The ancient Chinese buildings are mostly belonged to wood structure buildings, and because the ancient Chinese buildings are damaged by sunlight and rain for a long time and are damaged by termite, the surfaces of the members are corroded and aged, and the safety of the buildings is reduced year by year. At present, the reinforcing and repairing of the ancient building timber components are generally carried out by replacing the whole beam or grouting and filling holes and cracks. The methods improve the safety of the ancient buildings to a certain extent; the method has the disadvantages that the beam column of the building needs to be unloaded before the beam column is replaced, potential safety hazards exist, the construction speed is low, and the manufacturing cost is high. In addition, the appearance of the replaced component is obviously different from the original part, and the principle of 'repairing old as old' of the historic building with cultural relic value is violated.
The corrosion of beams and purlin members in the wood structure building mainly occurs at two ends and the upper part of the members, the beam members close to a patio, a door and a corridor are generally more seriously damaged than the beam members inside the building, particularly, in some hui buildings such as a temple, a house Xian and a temple, the buildings are overhauled all the year round, rain and water leakage can occur at the cornice position, the appearance of the beam members is good, but the medullary part is in a special damage form under the rotten condition, and the phenomenon is also relatively common.
The method and the technology for reinforcing and repairing the wood beam have a large number of theories and experimental analyses at home and abroad, but basically, the method is a reinforcing method of directly sticking steel, cloth materials, embedded ribs and the like on the surface of an original beam member, a reinforcing technology which mainly aims at improving the bearing capacity or rigidity of a damaged test piece is adopted, and the reinforcing treatment mode is unidirectional, irreversible and irreversible, and has large influence on the appearance of the wood beam. Particularly, for the reinforcement technology which can protect the appearance of the building and can perform secondary reinforcement, how to systematically research the design theory of the structural system of the reinforcement technology does not form a theoretical basis and an analysis design method for guiding engineering application at present, and no corresponding specification can be followed. Particularly, when the ultimate bearing capacity of the reinforcing beam is calculated, only the ultimate bearing capacity of elastic development is usually considered, but the ultimate bearing capacity of plastic development is not considered, so that the performance of the reinforcing beam cannot be objectively reflected, and a reasonable theoretical basis cannot be provided for engineering application.
Disclosure of Invention
The invention aims to provide a method for calculating the ultimate normal section bearing capacity of a beam capable of realizing a reinforcement technology which protects the appearance of a building and can be reinforced secondarily.
In order to achieve the above purpose, the solution of the invention is:
a method for calculating the ultimate bearing capacity of a normal section of a CFRP plate reinforced core beam, wherein the CFRP plate is used as a reinforcing material and is attached to the bottom of a core material to reinforce the core material, and the core material is arranged in a tension area of a shell of the beam to reinforce the beam; the method comprises the following steps:
(1) making basic assumption on the reinforcing process;
(2) calculating the stress-strain relationship of the cross section of the core material under the condition that each material in the reinforced core beam is damaged;
(3) calculating the height of the compression area of the cross section of the core material and the height of the plastic development of the compression area of the cross section of the core material under the condition that each material is damaged;
(4) and calculating the bending bearing capacity of the normal section of the reinforced core beam under the corresponding material damage condition according to the height of the compression area of the cross section of the core material under the condition that each material is damaged and the height of the plastic development of the compression area, so as to obtain the limit bearing capacity of the normal section of the reinforced core beam, which takes the plastic development into consideration.
The basic assumption of step (1) includes:
(11) the contribution of the original beam shell to the reinforced core beam is assumed to be zero;
(12) the cross section of the core beam is supposed to keep a plane before and after deformation;
(13) before the core beam tension area is cracked, the reinforcing material and the core material are in coordinated deformation, and the bonding slippage phenomenon does not occur;
(14) assuming that the compression constitutive model of the core material is an ideal elastic-plastic model, and the tension constitutive model is an linear elastic model;
(15) the constitutive model of the CFRP plate is assumed to be a linear elastic model.
The core material is wood and comprises wood fibers; the material failure situations comprise:
failure by wood fiber stretch-breaking of the core material under tension;
failure of the wood fibers of the compressed core material to reach ultimate strain;
the CFRP panel reaches ultimate strength induced failure.
The step (2) comprises the following steps:
the stress-strain relationship of the cross section of the core material in the case of breakage of the wood fiber of the core material under tension caused failure was calculated as follows:
wherein:represents the ultimate tensile strain of the wood fibers of the core material;
represents the yield stress strain of the wood fibers of the core material;
h represents the height of the cross section of the core material;
xca height of the compression zone representing a cross-section of the core material;
xcpa height representing a plastic development of a compression zone of a cross section of the core material;
represents the ultimate tensile stress of the wood fibers of the core material in consideration of the reduction in strength;
represents the yield compressive stress of the wood fiber of the core material without considering the strength reduction;
Rσrepresents the ratio of the maximum tensile stress to the maximum compressive stress of the wood fibers of the core material;
the stress-strain relationship of the cross section of the core material in the case where the wood fiber of the compressed core material reached the ultimate compressive strain to cause failure was calculated as follows:
wherein:to representUltimate compressive strain of the wood fibers of the core material;
γεrepresents a ratio of ultimate plastic strain to elastic strain of the wood fiber of the core material;
calculating the stress-strain relationship of the cross section of the core material under the condition that the CFRP plate reaches the ultimate strength to cause the damage according to the following formula:
wherein:representing ultimate tensile strain in the CFRP plate constitutive model;
representing ultimate tensile stress in the CFRP plate constitutive model;
αEexpressing the ratio of the elastic modulus of the CFRP plate to the elastic modulus of the core material;
h represents the height of the cross section of the core material.
Calculating the height of the compression area of the cross section of the core material under the condition that each material is damaged in the step (3), wherein the height of the compression area comprises the following steps:
the height of the compression zone of the cross section of the core material in the case of breakage caused by the breakage of the wood fibers of the core material under tension is calculated as follows:
wherein: a. theFRepresents the area of the reinforcement material;
b represents the width of the cross section of the core material;
the height of the compression zone of the cross section of the core material in the case of failure of the wood fibers of the compressed core material due to reaching the ultimate compressive strain was calculated as follows:
the height of the compression area of the cross section of the core material in the case of the CFRP plate reaching the ultimate strength to cause the damage is calculated according to the following formula:
calculating the plastic development height of the compression area of the cross section of the core material under the condition that each material is damaged in the step (3) comprises the following steps: and (3) calculating the height x of the plastic development of the compression area of the cross section of the core material under the corresponding material failure condition by combining the stress-strain relation of the cross section of the core material under the condition that each material fails, calculated in the step (2)cp。
The step (4) comprises the following steps:
and (3) calculating the normal section bending bearing capacity of the reinforcing core beam under the condition of damage of each material according to the following formula:
wherein: m represents the bending bearing capacity of the normal section of the reinforced core beam;
xcaccording to x in the corresponding damage situation in step (3) respectivelycValue calculation;
xcpaccording to x in the corresponding damage situation in step (3) respectivelycpAnd (5) value calculation.
The step (4) further comprises:
taking the minimum value of the flexural bearing capacity of the normal section of the reinforcing core beam under the condition of failure of each material as the limit bearing capacity of the normal section of the reinforcing core beam considering the plastic development.
Due to the adoption of the scheme, the invention has the beneficial effects that: the invention provides a method for calculating the normal section bearing capacity of a CFRP plate reinforced core beam, which provides theoretical guidance for the design of reinforcing the core beam by adopting the CFRP plate and ensures that the core beam reinforced by adopting the method can meet the design requirement, thereby effectively protecting the intact appearance of a building, meeting the requirement on strength and realizing secondary reinforcement.
Drawings
FIG. 1a is a schematic illustration of a core material reinforced with CFRP sheets in an embodiment of the invention;
FIG. 1b is a schematic illustration of the shell of the primary beam in an embodiment of the present invention;
FIG. 1c is a schematic illustration of a reinforced core-stiffened beam made in accordance with an embodiment of the present invention using the reinforcing core shown in FIG. 1a to reinforce the shell of the original beam shown in FIG. 1 b;
FIG. 2 is a graph of a constitutive relation model of a core material in an embodiment of the present invention;
FIG. 3 is a graph of a constitutive relation model of a CFRP panel in an embodiment of the invention;
FIG. 4a is one of schematic calculated height diagrams of a compression zone of a cross-section of a core material in an embodiment of the invention;
FIG. 4b is a second schematic view of the calculation of the height of the compression zone of the cross section of the core material in the embodiment of the present invention;
FIG. 5a is one of the schematic diagrams of the calculation of the normal section bending bearing capacity of the core-mounted wood beam in the embodiment of the invention;
FIG. 5b is a second schematic diagram illustrating the calculation of the flexural bearing capacity of the core-embedded wooden beam in the embodiment of the invention;
fig. 5c is a third schematic diagram of the calculation of the flexural bearing capacity of the front section of the core-mounted wood beam in the embodiment of the invention.
In the drawings: 1. a core material; 2. an original beam shell; 3. CFRP board.
Detailed Description
The invention will be further described with reference to examples of embodiments shown in the drawings.
Aiming at the problem that the technology which can protect the appearance of an ancient building and can strengthen a beam for the second time is lack of a technology for theoretical research in the prior art, the invention provides a method for calculating the ultimate bearing capacity of a normal section of a CFRP (carbon fiber reinforced composite) plate reinforced core beam. In the technology for reinforcing the core beam by the CFRP plate, the CFRP plate 3 is used as a reinforcing material to reinforce the core material 1, and the reinforced core material 1 is placed in a tension area of an original beam shell 2. The CFRP board 3 is attached to the bottom of the core material 1. FIG. 1a is a schematic illustration of a core reinforced with CFRP sheets; FIG. 1b is a schematic view of the original beam shell, wherein the void region is the tension region; FIG. 1c is a schematic view of the reinforced core beam of FIG. 1a after the reinforcing core has reinforced the original beam shell of FIG. 1 b. In this embodiment, the core material is wood, including wood fibers.
The invention provides a method for calculating the ultimate bearing capacity of a normal section of a CFRP (carbon fiber reinforced plastics) plate reinforced core beam, which comprises the following steps of:
in the first step, the following basic assumptions are made about the consolidation process:
1) the contribution of the original beam shell to the reinforced core beam is not considered, namely the contribution of the original beam to the reinforced core beam is zero;
2) the cross section of the core beam is supposed to keep a plane before and after deformation, namely, the assumption of a plane section is met;
3) if the reinforcing material (namely the CFRP plate) and the core material are in coordinated deformation before the tension area of the core beam is cracked, the bonding slippage phenomenon does not occur;
4) assuming that the core material is an ideal elastic-plastic model by the tension constitutive model, and an linear elastic model by the tension constitutive model, as shown in fig. 2. Wherein the core material has a modulus of elasticity under compressionAnd modulus of elasticity in tensionThe same numerical value is taken as the numerical value,getWherein,is the ultimate compressive strain of the wood fibers of the core material,is the yield pressure strain of the wood fibres of the core material,is the ultimate tensile strain of the wood fibers of the core material.Represents the yield compressive stress of the wood fibers of the core material; sigmawRepresents the stress of the wood fibers of the core material; epsilonwIndicating the strain of the wood fibers of the core material.
5) Assuming that the CFRP panel considers only the strength in the wood fiber direction of the core material, the stress is equal to the product of the strain and its elastic modulus, but its absolute value is not greater than its corresponding strength design value, the constitutive model takes the linear elastic model, as shown in fig. 3. Wherein,represents the ultimate tensile strain of the CFRP panel;the ultimate tensile stress in the CFRP panel constitutive model is represented. SigmaFRepresents the stress of the CFRP plate;representing the tensile elastic modulus of the CFRP plate;represents the ultimate tensile strain of the CFRP panel; epsilonFStrain of the CFRP panel is indicated.
And secondly, according to the assumption of a flat section, obtaining the stress-strain relation of the cross section of the core material under the condition that each material in the reinforced core beam is damaged, wherein the stress-strain relation comprises the following steps:
the stress-strain relationship of the cross section of the core material in the case of breakage of the wood fibers of the core material under tension caused failure was calculated according to the following formula:
wherein: represents the ultimate tensile strain of the wood fibers of the core material;
represents the yield stress strain of the wood fibers of the core material;
h represents the height of the cross section of the core material;
xca compression zone height representing a cross-section of the core material;
xcpa height representing a plastic development of a cross-sectional compression zone of the core material;
the ultimate tensile stress of the wood fiber of the core material under the condition of considering the strength reduction (namely, under the condition of considering the reduction of the tensile strength by defects such as knots, holes, drying shrinkage cracks and the like in a tensile region of the wood);
representing the yield compressive stress of the wood fibers of the core material without considering the reduction of the strength (i.e. without considering the reduction of the tensile strength by defects such as knots, holes and drying shrinkage cracks in the tensile region of the wood);
Rσthe ratio of the maximum tensile stress to the maximum compressive stress of the wood fibers of the core material is expressed.
The stress-strain relationship of the cross section of the core material in the case where the wood fiber of the compressed core material reached the ultimate compressive strain to cause failure was calculated according to the following formula:
wherein:represents the ultimate compressive strain of the wood fibers of the core material;
γεthe ratio of the ultimate plastic strain to the elastic strain of the wood fibers of the core material is indicated.
Calculating the stress-strain relationship of the cross section of the core material under the condition that the CFRP plate reaches the ultimate strength to cause the damage according to the following formula:
wherein:representing ultimate tensile strain in the CFRP plate constitutive model;
representing ultimate tensile force in the CFRP plate constitutive model;
αEexpressing the ratio of the elastic modulus of the CFRP plate to the elastic modulus of the core material;
h represents the height of the cross section of the core material.
Thirdly, according to the formulas and the static balance conditions of the cross section in the second step, the height of the compression area of the cross section of the core material is obtained, as shown in fig. 4a and 4b, the method comprises the following steps:
the height of the compression zone of the cross section of the core material in the case of failure caused by the tensile breakage of the wood fibers of the core material under tension is calculated according to the following formula:
wherein: x is the number ofcIndicating the height of the compression zone of the cross section of the core material in the damage caused by the tensile breaking of the wood fibers of the core material under tension;
AFrepresents the area of the reinforcement material;
b represents the width of the cross section of the core material;
the height of the compression zone of the cross section of the core material in the case of failure of the wood fibers of the compressed core material due to reaching the ultimate compressive strain was calculated according to the following formula:
wherein: x is the number ofcIndicating the height of the compression zone of the cross-section of the core material in the case of failure caused by the wood fibers of the compressed core material reaching the ultimate compressive strain.
Calculating the height of the compression area of the cross section of the core material under the condition that the CFRP plate reaches the ultimate strength to cause damage according to the following formula:
wherein: x is the number ofcIndicating the height of the compression zone of the cross section of the core material in the case of failure caused by the CFRP panel reaching ultimate strength.
In the context of figure 4b of the drawings,representing the compressive strain of the wood fibers of the core material;representing the tensile strain of the wood fibers of the core material;representing the tensile strain of the tensile reinforcement (CFRP panel).
Fourthly, calculating the height x of the plastic development of the compression area of the cross section of the core material under the corresponding material failure condition by combining the stress-strain relation of the cross section of the core material under the condition that each material is failed calculated in the second stepcp。
And fifthly, as shown in fig. 5a, 5b and 5c, calculating the normal section bending bearing capacity of the reinforcing core beam under the condition of material failure according to the following formula:
wherein: m denotes the post-consolidation settingThe normal section of the core beam is subjected to bending bearing capacity; x is the number ofcAccording to x in the corresponding destruction situation in the third stepcValue calculation; x is the number ofcpAccording to x in the corresponding damage situation in the fourth stepcpAnd (5) value calculation.
And taking the minimum value as the ultimate bearing capacity of the normal section of the reinforced core beam considering the plastic development in the bending bearing capacity of the normal section of the reinforced core beam under the condition that each material is damaged.
In the context of figure 5c, the figure,represents the tensile stress of the wood fibers of the core material; fFThe resultant force of the reinforcement material (CFRP panel) is shown.
And taking the minimum value as the ultimate bearing capacity of the normal section of the reinforced core beam considering the plastic development in the bending bearing capacity of the normal section of the reinforced core beam under the condition that each material is damaged.
The ultimate bearing capacity of the normal section of the core-placed wood beam obtained by the method can be used as a guide for relevant theoretical research and engineering application, and a reinforced core-placed wood beam which can meet the design requirement can be obtained in an auxiliary manner.
In general, a core-placed wood beam for composite reinforcement of a CFRP panel, which is designed, should satisfy the following functional requirements within a specified design life:
(1) can bear various possible effects during normal construction and normal use;
(2) the control requirements of various indexes of the structure can be met during normal construction and normal use;
(3) the working performance is good when the device is used normally;
(4) sufficient durability under normal maintenance;
(5) the necessary overall stability is maintained during and after design-specified contingencies.
The above requirements for the function of the structural member of the core-placed wood beam reinforced by the CFRP plate are to have sufficient strength substantially, to be able to bear the internal force generated by the most adverse load effect, and to meet the requirements of the limit state of the bearing capacity. In addition to this, the economics and operability of the design must be considered.
The design of the core-placed wood beam structural member reinforced by the CFRP plate is mainly carried out according to the following steps, and an economic, reasonable and feasible design scheme is often obtained after repeated modification calculation for several times:
(1) determining a secondary internal force of the structure;
(2) according to the use requirements and the drawn overall scheme and structural form, the existing design and related data are referred to, and the section size of the reinforced core-placed wood beam and the thickness and length of the CFRP plate are preliminarily determined;
(3) calculating the maximum effect of the load effect combination and the control section by adopting an internal force analysis model;
(4) and estimating the quantity, the size and the arrangement mode of the CFRP plates according to the design internal force and the preliminarily drawn section size of the control section in the bearing capacity limit state and the normal use limit state, and carrying out reasonable arrangement. If the CFRP plates cannot be reasonably arranged, returning to the step (2) and modifying the section size;
(5) checking and calculating section stress in a construction stage, a conveying and mounting stage and a using stage;
(6) and checking and calculating the anchoring length.
In conclusion, the invention provides a method for calculating the normal section bearing capacity of the CFRP plate reinforced core beam, which provides theoretical guidance for the design of reinforcing the core beam by adopting the CFRP plate and ensures that the core beam reinforced by adopting the method can meet the design requirement, thereby effectively protecting the intact appearance of the building, meeting the requirement on strength and realizing secondary reinforcement.
The embodiments described above are intended to facilitate one of ordinary skill in the art in understanding and using the present invention. It will be readily apparent to those skilled in the art that various modifications to these embodiments may be made, and the generic principles described herein may be applied to other embodiments without the use of the inventive faculty. Therefore, the present invention is not limited to the embodiments described herein, and those skilled in the art should make improvements and modifications within the scope of the present invention based on the disclosure of the present invention.
Claims (6)
1. A method for calculating a normal section ultimate bearing capacity of a CFRP board reinforced core beam, wherein the CFRP board is attached to the bottom of a core material as a reinforcing material to reinforce the core material, and the core material is further disposed in a tension area of a shell of the beam to reinforce the beam, characterized in that: the method comprises the following steps:
(1) making basic assumption on the reinforcing process;
the basic assumptions include: (11) the contribution of the original beam shell to the reinforced core beam is assumed to be zero; (12) the cross section of the core beam is supposed to keep a plane before and after deformation; (13) before the core beam tension area is cracked, the reinforcing material and the core material are in coordinated deformation, and the bonding slippage phenomenon does not occur; (14) assuming that the compression constitutive model of the core material is an ideal elastic-plastic model, and the tension constitutive model is an linear elastic model; (15) a linear elastic model is assumed to be taken as a constitutive model of the CFRP plate;
(2) calculating the stress-strain relationship of the cross section of the core material under the condition that each material in the reinforced core beam is damaged;
the core material is wood and comprises wood fibers; the material failure situations comprise: failure by wood fiber stretch-breaking of the core material under tension; the wood fibers of the compressed core material reach damage caused by extreme compressive strain; failure of the CFRP panel to ultimate strength;
(3) calculating the height of the compression area of the cross section of the core material and the height of the plastic development of the compression area of the cross section of the core material under the condition that each material is damaged;
(4) and calculating the bending bearing capacity of the normal section of the reinforced core beam under the corresponding material damage condition according to the height of the compression area of the cross section of the core material under the condition that each material is damaged and the height of the plastic development of the compression area, so as to obtain the limit bearing capacity of the normal section of the reinforced core beam, which takes the plastic development into consideration.
2. The method for calculating the ultimate bearing capacity of the normal section of the CFRP plate reinforced core beam as recited in claim 1, wherein the method comprises the following steps: the step (2) comprises the following steps:
the stress-strain relationship of the cross section of the core material in the case of breakage of the wood fiber of the core material under tension caused failure was calculated as follows:
wherein:represents the ultimate tensile strain of the wood fibers of the core material;
represents the yield stress strain of the wood fibers of the core material;
h represents the height of the cross section of the core material;
xca height of the compression zone representing a cross-section of the core material;
xcpa height representing a plastic development of a compression zone of a cross section of the core material;
represents the ultimate tensile stress of the wood fibers of the core material in consideration of the reduction in strength;
represents the yield compressive stress of the wood fiber of the core material without considering the strength reduction;
Rσrepresents the ratio of the maximum tensile stress to the maximum compressive stress of the wood fibers of the core material;
the stress-strain relationship of the cross section of the core material in the case where the wood fiber of the compressed core material reached the ultimate compressive strain to cause failure was calculated as follows:
wherein:represents the ultimate compressive strain of the wood fibers of the core material;
γεrepresents a ratio of ultimate plastic strain to elastic strain of the wood fiber of the core material;
calculating the stress-strain relationship of the cross section of the core material under the condition that the CFRP plate reaches the ultimate strength to cause the damage according to the following formula:
wherein:representing ultimate tensile strain in the CFRP plate constitutive model;
representing ultimate tensile stress in the CFRP plate constitutive model;
αEexpressing the ratio of the elastic modulus of the CFRP plate to the elastic modulus of the core material;
h represents the height of the cross section of the core material.
3. The method for calculating the ultimate bearing capacity of the normal section of the CFRP plate reinforced core beam as recited in claim 2, wherein the method comprises the following steps: calculating the height of the compression area of the cross section of the core material under the condition that each material is damaged in the step (3), wherein the height of the compression area comprises the following steps:
the height of the compression zone of the cross section of the core material in the case of breakage caused by the breakage of the wood fibers of the core material under tension is calculated as follows:
wherein: a. theFRepresents the area of the reinforcement material;
b represents the width of the cross section of the core material;
the height of the compression zone of the cross section of the core material in the case of failure of the wood fibers of the compressed core material due to reaching the ultimate compressive strain was calculated as follows:
the height of the compression area of the cross section of the core material in the case of the CFRP plate reaching the ultimate strength to cause the damage is calculated according to the following formula:
4. the method for calculating the ultimate bearing capacity of the normal section of the CFRP plate reinforced core beam as recited in claim 3, wherein: calculating the plastic development height of the compression area of the cross section of the core material under the condition that each material is damaged in the step (3) comprises the following steps: and (3) calculating the height x of the plastic development of the compression area of the cross section of the core material under the corresponding material failure condition by combining the stress-strain relation of the cross section of the core material under the condition that each material fails, calculated in the step (2)cp。
5. The method for calculating the ultimate bearing capacity of the normal section of the CFRP plate reinforced core beam as recited in claim 4, wherein the method comprises the following steps: the step (4) comprises the following steps: and (3) calculating the normal section bending bearing capacity of the reinforcing core beam under the condition of damage of each material according to the following formula:
wherein: m represents the bending bearing capacity of the normal section of the reinforced core beam;
xcaccording to x in the corresponding damage situation in step (3) respectivelycValue calculation;
xcpaccording to x in the corresponding damage situation in step (3) respectivelycpAnd (5) value calculation.
6. The method for calculating the ultimate bearing capacity of the normal section of the CFRP plate reinforced core beam as recited in claim 5, wherein the method comprises the following steps: the step (4) further comprises: taking the minimum value of the flexural bearing capacity of the normal section of the reinforcing core beam under the condition of failure of each material as the limit bearing capacity of the normal section of the reinforcing core beam considering the plastic development.
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| CFRP剥离对CFRP抗弯加固钢筋混凝土梁正截面承载力影响分析;李艳 等;《建筑结构》;20101130;第40卷(第11期);第114-116页 |
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