| In recent years, the staggered truss steel framing system caused the extensive concern of engineering and academic circles of home and abroad, and developing this system fits our country residence construction development direction. Owing to the lagging of theory research, the internal research achievements is still inadequate in to be used to lay down the design code (specification) and guide design of engineering at present, so the project of this system is still empty in our country. In order to enrich and perfect the exisiting theory research achievements, and promoting the application of staggered truss steel framing system in our country, static force capability, stability problem and structure P-A effect have been done in this text; Combines current national design code (specification) and abroad research achievements, propose the elastic design methods and suggestions of the staggered truss steel frame.Through the analysis of receiving force performance of staggered truss frame, this paper clearly proposed the principle that nodes construction scheme should be defined according to the plane truss form for the first time. By way of research staggered truss system space cooperation work principle, the text has systematically given out the plane structure computational module and the elastic static computational method, and provides a detailed calculation example. This method has overcome the shortcoming of plane analysis method in the past that cannot consider twisting effect. In contrast with the finite element specialized program, the result indicate that our method is not only simple, practical, but also in calculation precision, especially structure displacement calculation precision, is superior to the Steel Design Series 14 of American Institute of Steel Construction. At the same time, this paper has analyzed the manufacturing method of column footing, and came to the conclusion that the hinged connection scheme can make structure internal force distribute more reasonable, and economically superior to rigid connection one.Using the analysis method, the calculating method and practical formula of transverse and longitudinal column effective length coefficient of staggered truss framing have been done systematically andcompletely at the first time. During the transverse analysis, as the discussion of frame bracing condition that exists in the new vision < Code for Design of Steel Structures>GB50017-2002 has been lead into the stability analysis of staggered truss system, the concept of strong and weak bracing staggered truss system, and the concrete dividing standard are also given, so that makes the staggered truss stable theory have a good link with the new code, and provide theory guarantee for designers. The column effective length of strong bracing system can be calculated according to current design code, when consider the axial force changing impact on its effective length of the column, this text has offered the 'G coefficient of correction' method. For weak bracing system, this paper provided the concrete formula of calculating the effective 1 ength coefficient of column. During longitudinal analysis, the calculating method of column effective length has been given out, according to different longitudinal connecting beam.Consulting analysis method of current design code (specification) on the "P-A" effect of steel frames of each country, the geometry nonlinearity capability of staggered truss system has been analyzed in this text; those will fill the blank space of staggered truss framing research aspect. When the elastic design method is used, the paper proposes the recommendation that designer can not consider second-order effect on structural internal force, but must consider the effect on drift computing, and also gives a simplification method for calculating the second-order drift.Base on above research achievements and referencing current design codes and research documents, this text has done overall discussions on the elastic design method, the chief works includin...
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