2. Article 5.0.6 of the Unified Standard for Acceptance of Construction Quality of Building Engineering (GB 50300-200 1): If the inspection unit does not meet the requirements and is considered safe by the original design unit, it can be accepted. According to the project management of the first-class constructor, when the testing unit fails to meet the requirements, it can be accepted under the condition that the original design unit thinks it is safe. Take "liability for breach of contract" for acts that do not meet the requirements.
3. If the grid solder ball is made of pressed steel plate, the thickness tolerance of the steel plate is close to +2.5mm, and the deviation specified in the "strong gauge" does not exceed 13% and1.5 mm. What shall we do? We can thicken the steel plate 1mm when making it, so as to avoid quality inspection and trouble.
4. In our country, it is not allowed to design the workshop of crane with more than 20 tons according to the portal frame specification. The main reason is that the deviation of crane beam installation and crane track installation in China leads to the gauge jam, which increases the horizontal force by 4-5 times, leading to the violent shaking of the factory building and the normal use. In a word, any advanced design method can't be realized beyond the actual construction level, and it should conform to the national conditions (or "the processing strength of the company"). For example, the mast of a 20-ton crane is controlled at H/240 (China's H/400) according to American specifications, and no one wants to drive it, so it is ridiculous to save a little steel compared with the applicability of the factory building.
5. What kind of maintenance system needs to consider gust coefficient? (1), used for brittle materials. Such as glass curtain wall, gust coefficient must be adopted. (2) Under the action of gust, the gust coefficient can be ignored for the steel that can bear the temporary increase of load. (3) The maintenance system that shouldn't consider the gust factor considers the gust factor, which is one to one times higher than the main structure, which is not conducive to the safety of the main body.
6. There are three kinds of deflections: (1) and safety-related control standards. (2), reflect the installation quality control standards. (3) Control standard of beautiful appearance. For example, only 1/300 is considered when calculating the stability defects of single-layer reticulated shells, and excessive deflection will affect the structural safety. But the double-layer reticulated shell only controls the construction quality.
7. In the specification of space truss structure, "calculation of temperature stress" is limited to space truss structures supported on four sides.
8. The engineering principle in biology is the engineering design principle we pursue: (1), saving. Achieve maximum effect with minimum consumption. (2) security. Being an overloaded organism (building), even if it is partially damaged, will not endanger the overall survival. (3), simple and fast. "1.35* dead load" may not be considered when the calculated wind load of grid and reticulated shell is small and the ratio of permanent load to total load is less than 50%.
10, and the grid live load value should not be less than 0.5KNM2
1 1. If the additional load exceeds 25Kg/M2, whether there is concentrated load on the purlin should be considered.
12, China's "Load Code" is compared with American code: American code, the upward wind suction is large, the horizontal wind force at both ends is large, and the middle wind force is small. The approximate calculation method of lateral displacement in the Code of Portal Frame is only suitable for preliminary estimation, and the formal lateral displacement calculation is based on elastic integral calculation method.
13, wind load value of portal steel frame, according to the national technical measures for civil construction engineering design: l/h.
15, "end zone width"