Applied Mechanics and Materials Vols. 578-579

Abstract: The paper selected natural frequency and peak acceleration as comfort evaluation criteria. The author tested the new floor comfort under the human-induced loads. The author analyzed new floor comfort by selecting the worst possible scenarioes. The result indicates that the new floor satisfies the comfort requirement. The comparison of test value, theoretical value and finite element value of natural frequency proved that the finite element simulation was reasonable. The author analyzed comfort influencing factors of 7m×7m floor with the same simulation method and proposed a design proposal.

Abstract: Variable section portal frame is increasingly concerned and is widely used for its economy, beauty and short construction period, compared with other traditional structures. In-plane stability response of variable section columns of portal frames is the focus of this paper. Results are presented for parameters influence of variable section column on the in-plane stability bearing capacity with finite element analysis. References are proposed for practical application compared with computational formulas of Technical Specification for Steel Structure of Light-Weight Buildings with Gabled Frames.

Abstract: The author in this article conducts discussion on the square steel structure construction management of owner from the engineering management scheme to management in construction preparation stage, management of material procurement and inspection, steel structure assembling and connection, steel structure hoisting and other steps by combining with practical experience in the wide span aerial corridor steel structure work of "the 11th five year plan" technological transformation project on relocation of China Tobacco Hangzhou Cigaret Factory, which can be used for reference by craft brothers

Abstract: Through the experiment of the six node models, this article obtained the axial force-deformation curves of the web members, the equivalent stress distribution curves under different loads of the tower within the scope of the node plate length. The result shows that: the stress level in the node area increases with the growth of the radius-thickness ratio; the node without stiffening ribs prone to appear node plate out-of-plane buckling with a lower carrying capacity, and the pillar got a higher stress concentration at the front end of the node plate; while the exists of the stiffening rib can not only improve the bearing capacity of the tube plate nodes, but also avoid the early out-of-plane buckling of the node plate, the failure mode of these node is compression web member buckling failure, meanwhile, the distribution of the tower equivalent stress at the node area gets much more uniform. It follows that, the bearing capacity of the node is not only associating with the thickness of the node plate and the radius-thickness ratio, but also suffering the important influence of stiffening rib.

Abstract: The study of the existing data and steel structure design specification on node ultimate bearing capacity is limited to simply analyze its axial bearing capacity, but the study on the ultimate bearing capacity of the additional bending moment with nodes is very deficient. This article first briefly analyzed the size of the steel tube 's influence on the node additional bending moment from the aspects of node rigidity, and showed that basis and necessity of considering node additional bending moment in steel tube structure ,and then used three-dimensional four nodes elastic-plastic shell unit shell 181 and ideal elastic-plastic material to establish finite element model of K shape round steel tube tubular joint in the ANSYS finite element program, under the consideration of the geometric nonlinearity and material nonlinearity, respectively got the ultimate bearing capacity of K shape round steel tube tubular joint under the action of additional bending moment of different nodes ,analyzed the changes of mechanical property of the nodes after bearing of the additional bending moment, and showed that additional bending moment's influence rule on K shape round steel tube tubular joint ultimate bearing capacity.

Abstract: Using three-dimensional modeling software to design a kind of swinging rear underrun protective device, using the Ansys finite element analysis software, in accordance with the provisions of GB11567.2-2001, the rear underrun protective device applied static load analysis. The results show that the protective device and the body in the welding and bolt connecting two different cases, connected by bolts can effectively avoid the connection of stress concentration, and support as the main part of the force. But by welding, the connections exist obvious stress concentration, may to cause the protective frame dropping.

Abstract: As a new type of structure system suitable for the realization of building industrialization, assembly structure system is a trend in the development of steel structure engineering. In this paper, a kind of assembly truss beam steel frame system is proposed. The composition of system, the technology characteristic of components and connections are analyzed in detail. Meanwhile some problems need to be solved are also put forward.

Abstract: Restricted by the construction environment, the cable crane is an effective means to resolve the transportation of materials and component in the mountainous area. Compared with traditional gravity anchor base, cable crane fixed on the rock bolt foundation can take advantage of the bearing capacity of bedrock, and the construction method is simple and of good economic benefit. With the effect of the construction methods, design theory of geological conditions, and other factors, however, force calculation is much complicated. By analyzing the failure modes of rock bolt foundation, anchor foundation bearing capacity factors and multi anchorage effect on anchoring force, we studied the design process of rock bolt foundation, geotechnical strength parameters and the safety coefficient of reference value. Further, a construction way is proposed to improve the basic bearing capacity of rock bolt. Combing with engineering examples, we also demonstrated the security and reliability of the design method .

Abstract: Nonlinear finite element parameters analysis on the lattice type steel pipe concrete wind turbine tower, it shows the entire process of load bearing, failure mode and ultimate bearing capacity, researches on the influence law of aspect ratio, form of tower webs, tower diameter to thickness ratio and web member stiffness to tower column stiffness ratio on the ultimate bearing capacity and tower failure mode. The finite element analysis results shows that the tower aspect ratio λ, the diameter-thickness ratio γ of tower columns and the increase of stiffness ratio β between web members and tower columns has great influence on ultimate bearing capacity and failure mode, while the form of webs has small influence on that. with the increase of tower aspect ratio λ, the decrease of diameter-thickness ratio γ of tower columns and the increase of stiffness ratio β between web members and tower columns, the ultimate bearing capacity of this kind of latticed towers increase, the failure mode changed from Web local buckling to The combined damage of Web local buckling and the tension tower yield. This paper suggests that in the design of wind turbulent generator tower, the tower aspect ratio λ should be best controlled at 1/9, the bottom layers of this kind of tower should best use the re-divided web members, and other web member forms used on above layers, the diameter-thickness ratio γ of tower column should be taken less than 30, and the stiffness ratio β between webs and columns should be controlled less than 0.05 in order to avoid damage occurring on the tower columns earlier than the webs. The results can provide evidence for the engineering design.

Abstract: Explicit FEM model ANSYS-DYNA is applied to simulate dynamic response and damage morphology of RC beam under blast loading. The dynamic response and damage morphology of reinforced concrete beam is analyzed under the different burst points, different explosive locations with the same proportion distance. The results show that: Under the same blast loading, the extent of damage of RC beam under complex boundary was lighter than the simply supported beam because of the stiffness contribution of slab and column. Acceleration at the half span point of the beam was 1/3 of simply supported beam, and the explosion shock attenuation was obvious.