At the main beam support, the secondary beam and the negative reinforcement of the main beam support cross each other, so that the position of the negative reinforcement of the main beam moves down. When calculating the negative reinforcement of the main girder, single-row reinforcement H0 = h-(50 ~ 60) mm, double-row reinforcement H0 = h-(70 ~ 80) mm, and length S=2h 1+3b, additional transverse reinforcement shall be set.
In the range of 0.5 ~ 0.6 times of the beam height on both sides of the concentrated load point, the main tensile failure inclined crack can be caused. In order to prevent this kind of damage, additional transverse steel bars are set on both sides of the main beam, and the concentrated load at the lower part of the beam or within the height range of the beam section should be borne entirely by the additional transverse steel bars (hanging bars and stirrups).
Extended data:
Requirements for steel structure setting stipulate that:
1. Before welding, evenly heat the groove and the parent metal within the range of 100mm on both sides with gas welding or special baking gun, and measure the temperature with a surface thermometer to prevent the temperature from not meeting the requirements or local oxidation on the surface, and preheat the temperature.
2. When assembling and welding the backing plate and the arc striking plate, the surface cleanliness should be the same as that of the groove surface, the backing plate and the base metal should be closely attached, and the arc striking plate and the base metal should be welded firmly.
3. In case of rain or snow, welding should be stopped, and there should be wind shields and awnings around and above the joint of components. When the wind speed is greater than 5m/s, the welding shall be stopped. When the ambient temperature is below zero, preheating and post-heating measures should be taken according to regulations.
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