Steel structure design code

Steel structure design code

Structural design norm is the important basis that is engaged in structural design work, the regulation in norm is lower limit requirement, under normal circumstances, had achieved these basic requirement only, structural ability achieves the safety requirement that expects in use period likely and assure rate.

 Through the study of this course, it is expected to help you understand and master the provisions in the specification quickly, and apply the provisions in the specification to the steel structure design work correctly and flexibly.

I. General Provisions

   This section introduces the scope of application of technical and economic policies, specifications, design principles, design matters needing attention, and puts forward the key points of design application: three necessary conditions for good steel structure design include software application, mechanical knowledge, and the degree of mastery of specifications.

Terms and symbols

   This section introduces the meanings of steel structure terms and symbols, such as column web joint domain, steel and concrete composite beam, strength standard value, strength design value, etc., which is very helpful for students' understanding and memory, laying a good foundation for the following study and design work.

Three, design principles

        This section mainly introduces the contents and combinations of the ultimate state of the bearing capacity and the ultimate state of the normal use, selects the correct safety level and dynamic coefficient in the design work, and defines the special requirements and designs for fatigue design calculation

The principle.

4. Calculation of load and load effect

       1. Explain how to arrange and apply loads correctly according to specific conditions, reasonably determine the mode of load combination and load combination value coefficient, ensure the accuracy of the number of simultaneous acting loads and relevant coefficients, ensure the accuracy of the calculation results, and ensure the safety and economic rationality of the structure.

       2. Introduce how to ensure the consistency between the analysis model and the actual connection structure. The analysis methods (elastic, plastic, first-order and second-order) must meet the relevant requirements of the specification, ensure the accuracy and reliability of the analysis results, and ensure the safety of the structure.

5. Material selection

       1. The material selection principle of steel structure. According to the environmental temperature, stress state, connection method, steel thickness, load characteristics and importance of the structure, choose the brand and performance of steel, and ensure that the steel selected has all the qualification guarantees required by the specification.

      2, special circumstances the selection of steel requirements: to learn the structure of the need to check fatigue, using different connection ways and in different temperature range, the impact toughness of should have qualified assurance requirements, understand to steel, cast steel, Z their application conditions of the weathering steel and shall comply with the current national standards, ensure the quality of design.

      3. Selection requirements of connecting materials: welding rod, welding wire, flux, ordinary bolts, high-strength bolts, cylindrical head welding nails, bolts, rivets and anchor bolts shall be applied to the design of steel structures correctly and flexibly according to the current national standards in their respective application fields, use methods and in accordance with the current national standards.

Vi. Design index

        The strength and influencing factors of steel members and connections, the physical performance indexes of steel and steel castings, and the preconditions that need to reduce the strength design value, stability or connection of steel members should be grasped to ensure the accuracy of design results and structural safety.

7. Provisions on the deformation of structure or members

       Understand the design requirements of the code for the normal use and appearance of structures and components, master the design standards, design methods and design skills to meet the requirements of deflection and deformation.

8. Strength calculation of bending member

      This section needs to master the relevant provisions and requirements of the general steel code for flexural strength, shear strength, local compressive strength and converted stress calculation of the flexural members. According to the specific situation of the design project, the strength of the flexural members should be appropriately and reasonably designed, and the amount of steel used in the design should be scientifically saved.

The overall stability of bending members

X. Local stability of bending members

        1. Master the design and construction requirements of the general steel code for the local stability of steel structure flexural members, master the calculation method of the stability of web area pattern section when only transverse stiffeners are provided, so as to ensure the local stability of composite beams and save the amount of steel used in the design scientifically.

       2. For the design and construction requirements of beam supporting stiffeners, the general steel code should focus on the relevant provisions of the ratio of free outspread width of the compression flange to its thickness of the beam, as well as the precondition of relaxing the ratio of the compression flange to the width and thickness in the earthquake area, so as to meet the design requirements of local stability of the beam.

Xi. Calculation of strength after buckling of composite beam web

       Master the design and calculation requirements of composite beam webs considering the post-buckling strength, and make use of the post-buckling strength of composite beam webs as much as possible according to the specific situation of the design project to save the amount of steel used in the design.

12. Axial bearing member

       Master the design and calculation requirements of the strength and stability of axial compression members of steel structure, the section classification requirements of axial compression members, especially the correct calculation methods of the fineness ratio of members with different section forms around different coaxes for solid abdominal members.

Xiii. Tension bending member and compression bending member

       In this section, it is necessary to master the strength calculation of tension and compression members and the determination of the plastic development coefficient of the section. It is important to master the stability calculation (inside and outside of the plane) and design regulations for solid abdominal compression members when the bending moment ACTS in a symmetric plane.

The calculated length and allowable slenderness ratio of the member

       In this section, it is necessary to grasp the general steel code for the value of the calculated length in and out of the plane of the truss chord and its single series ventral bar, and grasp the relevant provisions for the value of the calculated length in and out of the plane of the cross inclined ventral bar when the intersections are connected.

Local stability of compression members

       Grasp the structural requirements and calculation provisions of the general steel code on the ratio of free outspread width to thickness of flange plate of compression members, the ratio of web height to thickness, the ratio of width to thickness of compression flange of box section, and the ratio of outer diameter to thickness of compression circular section, so as to ensure the local stability of members.

16. Fatigue calculation

       Grasp the critical value of the cycle number of stress change needed for fatigue calculation of steel structure, grasp the applicable scope of fatigue calculation in general steel code and the application method of allowable stress amplitude method for fatigue calculation.

Seventeen, node connection

       Master weld connection, fastener (bolt, rivet, etc.) connection, flange connection of combined I-beam, rigid connection between beam and column, calculation of plate at joint, calculation of support connection, etc.

Xviii. Structural requirements

       This section requires knowledge of weld joints, bolt and rivet connections, structural component requirements, crane beams and crane trusses, requirements for improving the brittle resistance of structures in cold areas, large-span roof construction, fabrication, transportation and installation requirements, protection and insulation requirements.

19. Plastic design

        Master the plastic design and calculation method of bending strength and shear strength of bending member and strength and stability of bending member when bending moment ACTS on one main plane of member in general steel code.

20. Steel tube structure

       It is clear that the applicable scope of steel tube truss structure is not directly subjected to dynamic loads, the requirements of yield strength less than or equal to 345 N/mm2 and flexural strength ratio less than or equal to 0.8 are grasped, and the preconditions and design regulations that can be regarded as hinge joints in truss analysis and the influence of eccentricity can be ignored by the tensile main.

Steel and concrete composite beam

       Master the design of composite beams, the calculation of shear joints, deflection and structural requirements