Design Specification for American Standard H-shaped Steel

Design Specification for American Standard H-shaped Steel

Separate Guijiao form

2. The steel grade of the column base should not be lower than the steel grade of the lower column, and Q235B can be used as the structural stiffener. For new base plates that bear tension, when the thickness of the steel plate is not less than 40mm, steel plates that comply with the current * * standard "Directional Performance Steel Plates for Thick Plates" ASTM B36 should be selected.

3. The shoe beams, rib plates, and partitions of the column base should be symmetrically arranged.

The design value of the bearing capacity of the column base should not be less than the design value of the bearing capacity of the lower section of the column.

5. The bearing capacity of the column foot joint should not be less than the node bearing capacity, and the joint should be penetrated with different qualities according to the weld form and stress state according to the following principles:

1) For joints that require the same strength as the base material to be welded into a robust I-shaped joint that requires full penetration, the quality grade should be one; The connection weld between the exposed column body and the bottom plate should be one *.

2) The appearance quality standard of the butt and corner joint combination welds that do not require partial penetration of the fillet weld for the bottom shaped joint should be II *. The appearance quality standard for other welds can be three *.

6. In seismic fortification areas, the column base nodes should be consistent with the seismic performance goals of the upper structure. The structure of the column base nodes should comply with the design principle of "strong points, weak components". When subjected to small earthquakes and seismic fortification intensity, the column base nodes should maintain elasticity. When subjected to impermeable ground action, the ultimate bearing capacity of the column base node should not be less than 1.2 times the full plastic bearing capacity of the lower section of the column.

7. The construction measures for exposed column bases should prevent water accumulation and ash accumulation, and reliable anti-corrosion and insulation measures should be taken.

8. The complex structure of large column base nodes should be determined through finite element analysis and should be verified through experiments to correct and improve the node structure

9. For plug-in column bases and external column bases, paint shall not be applied within the range of contact between steel columns and concrete; When installing the column base, the soil, oil stains, rust, and welding slag on the surface of the other columns should be cleaned with a grinding wheel.

9.5.3 Design of hinged column bases

The relatively connected column base is suitable for single leg column bases of steel columns or lattice columns subjected to axial forces (axial compression and axial tension). The H-shaped steel column base adopts a staggered connection, and the H-shaped steel connection column base generally adopts a flat plate column base structure. The staggered bolts can be set in one or two pairs. Hinged column bases also have plate hinge node practices (perimeter

9.5-3a) and the practice of swinging column base (Figure 9.5-3b).

The design content of H-shaped steel column base mainly includes the size, connection, and shear key calculation of the column base plate, and meets the structural requirements,

9.5-4 provides the form of the hinged column base and a schematic diagram of the pressure distribution on the bottom plate.