Steel structure workshop - — Crane beam design characteristics

Steel structure workshop & ndash; — Crane beam design characteristics of crane beam design of crane beam is simply supported ( Simple structure, convenient construction, is not sensitive to support subsidence) Common forms include: the type of steel beam, 1) , combination of h beam ( 2) , box beam ( 3) , crane truss ( 4) And so on. Crane beam by load permanent load ( Vertical) Dynamic loading, and its direction is horizontal, level, is characterized by repeated role, easy to cause fatigue failure. As a result, the demand for steel is higher, in addition to the tensile strength, elongation, yield point and other conventional requirements, to ensure that the impact toughness of qualified. Crane beam structure system composed of 1, 2, crane beam crane beam load of the crane brake beam or truss beam load directly under three directions: vertical load ( System weight and weight) , transverse horizontal load ( Brake force and card rail force) Vertical and horizontal load ( The brake force) 。 Crane beam design does not consider the longitudinal horizontal load, according to the two-way bending design. Vertical load, lateral horizontal load and vertical horizontal load. Vertical load including crane and its weight, weight of crane beam. Crane collided in rail junction, and dynamic effect on beam. Design to increase the method of wheel pressure into consideration. Transverse horizontal load generated by the card rail force ( Track irregularity) To produce lateral horizontal force. The rules and regulations of crane load calculation load, crane transverse horizontal load standard value should be taken across the car and rated lifting weight of gravity gravity g Q the sum is multiplied by the percentage of the following: soft hook crane: Q≤ When 100 kn, take 20% Q = 150 ~ 500 kn, take 10% Q≥ When 750 kn, take hard hook crane: 8% 20% GB50017 regulation, heavy duty, Level of job of A6 ~ A8) Crane beam, due to the crane swing on the horizontal strength standard values for each wheel pressure: crane beam of internal force calculation when calculating the internal force of crane beam, due to the crane load as the moving load, should first according to the structural mechanics method determine the internal force influence line in the most disadvantageous position of crane load required, then click here to get the maximum bending moment of crane beam and their corresponding shear, joints of maximum shear and lateral horizontal loads in a horizontal direction of maximum bending moment. When calculating the strength, stability and deformation of crane beams, according to the two cranes consideration; Fatigue and the calculation of deformation, the crane load standard values, regardless of the power coefficient. 1, under moving load calculation, first of all, according to the influence line method to determine the most unfavorable position of the load; 2, secondly, the maximum bending moment and shear force of crane beam, bearing the maximum shear, transverse horizontal load under the action of the maximum bending moment of 3, strength and stability calculation, according to two cranes commonly the most unfavorable load consideration; Fatigue calculation is according to a world's largest crane. Of the crane beam cross section calculation cross section design of crane beam is the most adverse internal force, according to chapter 5 section selection methods try to choose crane beam cross section. Cross section checking section checking, assume by crane beam under vertical load and horizontal horizontal load by strengthening on the flange of crane beam, brake beam or truss under braking, and ignore the transverse horizontal load generated by the eccentric effect. Overall stability calculation has brake structure of crane beam, the lateral bending stiffness is very big, the overall stability guaranteed, do not need to check. Strengthen the top flange of crane beam, and the overall stability formula: stiffness checking calculation of the crane beam stiffness, should according to the effect of one of the largest crane load standard value calculation, and do not take the power coefficient. Crane beam vertical deflection approximate calculation formula of flange and web connection weld on the flange weld in addition to the horizontal shear stress, also by the crane wheel pressure caused by the vertical stress; Bottom flange weld only by the horizontal shear stress between the flange and web. For heavy duty crane beam, the flange and web connection should be used in figure 7. 91 T connection weld penetration, weld quality is not lower than the secondary, need not calculating the weld strength at this time. Wall beam structure layout workshop column spacing greater than 12 m, set the wall between column frame column, wall frame column spacing is 6 m; On the metope of along, along, tallied window frame under a setting along the wall beam; Set up on the wall beam bracing reduce the vertical deflection of wall beam, set in the top of the wall beam suspension, wall beam can be made according to the volume of column space beam or continuous beam.