1、Specialty and construction of steel structures in civil engineering 钢结构在土木工程中的特点与施工工艺资料来源： Design of prestressed concrete structures设计题目： 钢结构在土木工程中的特点与施工学生姓名： 学院名称： 专业名称： 班级名称： 学 号： 指导教师： 教师职称： 完成时间： Specialty and construction of steel structures in civil engineering1、 Civil engineering steel struct
2、ure characteristics1.1、Stiffness The suitability parameters of the stiffness of the vibration, deformation, etc. is determined by the stiffness of the member, and thus is determined by the stiffness of the structural system. The actual stiffness of the structural system to determine the distribution
3、 of its member and the connecting member. But simply to the stiffness of the member is determined by the geometric cross-sectional properties of the material and the modulus of elasticity of the material, the modulus of elasticity of the structural steel 200GPa and the elastic modulus in normal dens
4、ity concrete compressive strength in the range of 20-40Gpa the amount is usually in the range 20-28GPa; even for high-strength concrete, the elastic modulus, but also between 40-45GPa, therefore, the steel structure of the steel concrete times and about five times, so the rigidity of the steel struc
5、ture has a significant advantage.1.2、Strength Generally, the structural member the ability to withstand or accommodate the effect of action by the strength of the material determined. Can make use of the relevant national standards to determine the performance of the structural steel member, and the
6、se standards are listed in the material of the steel structure can be used, such as building the structural steel to meet the the CSA standard ASTM standardA992/A992M or CAN / CSA G40.20/C40.21 and other relevant standards. In recent years, construction steel has undergone great changes, the past bu
7、ilding structure with tensile strength and yield strength data were drawn from the history of CISC (2006), and Canada for structural steel engineering and building structural steel standard set of seven steel grades and 8 intensity level. According to the yield strength range of 260 to 700 MPa. But
8、not all kinds of steel have all the intensity level, so if a particular building steel structure design, choice of steel types and intensity level is very important. Whole steel structure can reduce material consumption, reduce structural weight, lower support member and the size of the foundation,
9、and ultimately reduce the cost of the entire structure of the building.1.3、Ductility Ductility refers to a material stretch in the process of plastic deformation without fracture. Under normal circumstances the ductility is the structural design, in particular the more important characteristics of t
10、he seismic design parameters, The earthquake surviving building directly dependent on the experience large inelastic deformation the hysteresis energy consumption when the main structural framework. Steel structure can be said is the most widely used, one of the toughest engineering materials. Howev
11、er, the inherent ductility of the material does not always into the inherent ductility of the structure of the building, so to fully recognize this and take appropriate design strategies and reliable, stable stagnation of consumer mechanism. Usually a design has the ductility response there should b
12、e enough material cross-section, material ductility and ductility of the structure and ductility. The capabilities and needs of the ductility values to the variable level of ductility, curvature ductility (ductility) and displacement ductility (ductility) match. Although strain ductility of the stee
13、l structure is relatively high, but because of the uneven force stability flexural members, member curvature ductility is often insufficient.1.4、Toughness Toughness absorb energy and plastic deformation indicators measure the material before breaking toughness. It can resist a notch portion unstable
14、 crack propagation. Resilience usually means that the steel structure can withstand a relatively large industrial deformation in the manufacture, installation and use of the process, the steel structure is a very important feature. Precisely because of the toughness of the steel members to reduce th
15、e possibility of cracks in the production process of bending, shearing, punching, forging, drilling. Must have sufficient fracture toughness of the steel structure, in particular by the alternating load and impact load of the building structure to have this feature. The fracture toughness of the steel structure is very sensitive to temperature conditions, and decreases as the temperature decreases. Design of steel structures in cold weather areas, we must first consider the toughness. Relatively speaking, low-carbon the niobium steel is high carbon steel ingredients steel is mor
