Research On The Performance And Design Of Staggered-truss

The staggered-truss structure is a new type of structure that evolved on the basis of thesteel frame structure. The structure system is economic and efficient, and coincide with therapid development of economy and steel structure industry in China,so its use will more andmore.But the idea and principle of design that can be followed by staggered-truss structuredesign are very few, so the writer will study the performance and design of staggered-trussstructure.At first,the writer use Sap2000software.And to conduct Pushover analysis of theVierendeel、Pratt and Mixed staggered-truss structure model.For researching the performanceof structure,analyze systematically base shear-displacement curves、maxium displacement ofthe top、maxium story drift、capacity spectrum-response spectrum curves、development anddistribution of plastic hinge of the three structures. The results prove that for the Vierendeelstaggered-truss structure,the seismic response degree is strong,seismic performance ispoor,but for Pratt and Mixed staggered-truss structure, the seismic response degree isweak,seismic performance is good;That the overall seismic performance of Vierendeelstaggered-truss structure is good, but its deformation is not in conformity with thespecification requirements,the second、fourth and sixth floor is the weak story of Pratt andMixed staggered-truss structure; That the development of plastic hinge of Vierendeelstaggered-truss structure is unsatisfactory, it appeared in column firstly but did not appear inweb members what does not conform to design philosophy of the staggered trussstructure;That Pratt and Mixed staggered-truss structure carry out the original purpose thatweb member destroy first under loads and achieve the desired effect of "strong column, weaktruss".The second, the writer analyse the second group of models of different member sectionsise of in elastic-plastic static Pushover. analyze base shear-displacement curves、capacityspectrum-response spectrum curves、development and distribution of plastic hinge of themodel structures. The results show that deformation and lateral stiffness of truss which is composed of chord member and web member with different section size is more reasonable,and the seismic response of it is weak relatively; Truss should choose chord member and webmember with different section size.The last,the author analyze the internal force characteristics of the third group models ofdifferent kinds of truss under lateral static load.The conclusion shows that for Pratt and Mixedstaggered-truss structure,the joint of chord member and column、web member and column,web member and chord can be designed in accordance with hinge joint, Chord member can bedesigned according to continuous bending component;that for Vierendeel staggered-trussstructure without diagonal web member, the lateral force cannot be passed down,so the jointmust be designed in accordance with rigid joint.In a word, Mixed staggered-truss structure ismore economic and reasonable,so it is the most ideal structure.