Advanced Materials Research Vols. 1065-1069

Abstract: Correlation coefficients of mode shape between higher frequency modes and lower frequency modes are given. Then 17 high modes were initially selected as the dominant high modes in the analysis of wind-induced response, and cumulative mode correlation was used to judge the rationality of the method of selecting dominant high modals, so dominant modals of wind-induced response analysis are constructed. Based on these, the wind-induced vibration response of spherical Kiewitt cable dome was analyzed in frequency domain using CQC method. Through analyses of computational results, it is found that the selecting method of dominant modals by using the mode correlation coefficient can be applied in frequency domain analysis for wind-induced vibration response of cable dome structures. If the first 100 modals are considered into the analysis, the computational results obtained will be high precision.

Abstract: Dynamic response of civil engineering structures was monitored in the paper, on basis of the excellent properties of piezoelectric smart sensor. There were two experiments: One was to study the relationship between the loading frequency and the piezoelectric sensor output by concrete block cyclic loading test; the other was to study the relationship between the sensor output and the stress amplitude by steel cantilever beam dynamic test. The results show that piezoelectric sensors have a good linear output performance.

Abstract: The minimum web reinforcement specified by many codes of practice is intend to maintain adequate reserve strength and ductility. So, reasonable value of minimum stirrup ratio in reinforced concrete flexural members is a noteworthy problem, which is to prevent members occur inclined tension brittle failure in shear design. Especially in seismic design, in order to ensure the structural members to achieve ‘strong shear weak bending’ the condition, reasonably determine the minimum stirrup stirrup ratio is a key component to ensure ductile failure occurs. Analogy to determine the principles flexural members minimum reinforcement ratio, combined with European norms to determine the principles of the minimum rate of stirrup, an expression has been proposed in non-seismic reinforced concrete beam shear design with considering the ratio of shear span. The minimum shear reinforcement predicted by the proposed expression makes the required minimum stirrup ratio have been harmonized in shear design of both cases which in general flexural members and under concentrated load members.

Abstract: An experiment was performed about the bearing capacity of cold-formed thin-walled steel-OSB composite floor by the sand heap. The strain and deflection response of OSB board and steel beam is analyzed under the load; then the test process is simulated by ANSYS, the results of simulation are agreed with the experiment basically. Through the analysis of experiment and finite element simulation, the results indicate that the composite floor has enough bearing capacity and meets the requirement of the residential building completely.

Abstract: This studypaper analyzed the affecting factors affecting of strength of concrete in corrosion and expanding areas at initial stages of reinforcement corrosion by experimental resultss, and researched the transformation trend of experimental factors by difference analyzing in statistics. The results showed that the expanding force after steel corrosion remarkably influenceds the strength of concrete. At the same time, the reinforcement diameter and thickness of concrete cover also had clear influence on concrete strength when rust occurroccurrenceed. Therefore, when studying the influence of corrosion and expanding force on concrete strength, we should not only research the influence of reinforcement corrosion magnitude, but also consider other effects, such as steel diameter, thickness of concrete cover should be considered.

Abstract: Chemical bonded reinforcement is widely used in structural rehabilitation, retrofitting and strengthening. Pull-out test of bonded anchor in concrete block was widely used in research but it cannot reflect the practical behavior of bonded reinforcement in structure. 6 RC columns in which longitudinal reinforcements overlap with chemical bonding technique were tested under eccentric compressive loads. The failures of some columns were caused by weak bonding capacity while most were caused by yielding of steel. The failure mode depends on the overlap length of bonded reinforcement. The ultimate load, deflection curve and cracking situation of tested columns were similar with usual RC columns, but the values of rigidity were influenced by bonding strength and anti-sliding stiffness of anchorage. The mechanical properties of concrete column with chemical bonded reinforcement were also influenced by bonding construction quality.

Abstract: Four pairs of prefabricated reinforced concrete slabs were designed, cast, cured, assembled and test to investigate the flexural performance of prefabricated underground thin-wall box RC structure. One traditional integrated slab specimen with same size, material and reinforcement was also cast and test for comparison purpose. Four rebar constructional forms were conceived to compare the ability of transferring tension force between two slabs. Symmetric two-points monotonic static load test were performed to attain their flexural performance. The test results indicates: the prefabricated RC slab can provide better deformability and ductility, but the flexural bearing capacity is lower, comparing with cast-in-situ integrated RC slab; steel rebar form at seam have some effect on the flexural bearing capacity of prefabricated RC slab.

Abstract: Recently, polygon hole castellated steel beams have been studied and applied which had better social and economic benefits. But it brings more difficulties to extend castellated steel components that less studies of castellated bending members. In this essay, ANSYS that is a kind of finite element software had been used to analyze castellated bending members, and characteristics of stability bearing capacity in moment plane of regular hexagon hole castellated steel components had been studied that can provide references to engineering design.

Abstract: In the field of modern logistics, assembled steel racks are one of the most widely used structure forms. Hold-welding beams, as the main load-bearing component, were researched in this paper. Firstly, mathematical relationship between semi-rigid joint stiffness K and bearing capacity of hold-welding beams P were derived. Then, hold-welding beams which span were 2300mm, 3000mm, 3300mm and 3600mm were analyzed. When K varies from 0 to 30EI/L, the bearing capacity P was concluded. Finally, the most suitable joint stiffness was concluded respectively in four types of span.

Abstract: In the decoration integration of steel structure, overhead floor achieves a separation of decoration and structure. Overhead floor system is composed of steel bracket, beam and floor. Reasonable overhead floor structure to ensure the safety of the whole structure has important significance. In this paper, the new form of beams named the cold bending cap steel is proposed and the size design of the new beam is made. While maintaining the original beams on the basis of mechanical properties, the new form of beams increase effective use height above the floor. In addition, the construction technology, construction requirements, the error control of overhead floor system, etc. are summarized and some author's suggestions in terms of modular are made.