Time filter

Source Type

Wu F.,Hunan University | Huang H.,Hunan University | Zhou X.,Hunan University | Zhou X.,Lanzhou University | And 2 more authors.
Jianzhu Jiegou Xuebao/Journal of Building Structures | Year: 2011

U-shaped and inversed T-shaped prestressed precast component composite beams(PPCCB) were proposed to overcome the disadvantages of traditional prestressed concrete composite beams such as heavy self weight and the difficulty in transportation and erection due to the use of rectangular cross section. Three U-shaped PPCCB, three invertible T-shaped PPCCB and a cast-in-situ beam were tested. Failure mechanism, flexural capacity, short-term rigidity, deformation behavior and crack distribution were studied. Differences in cracking moment, ultimate bending moment, short-term rigidity and average crack interval between the calculated values based on the current code method and the experimental results were analyzed. Experiment results indicate that PPCCB and the cast-in-situ beam exhibit similar load carrying capability and deformation property. The calculated values of cracking moment, ultimate bending moment, short-term rigidity and average crack interval for PPCCB agree well with testing values. The calculated values of cracking moment and ultimate bending moment for PPCCB according to the cast-in-situ beams are more conservative than actual results. The finite element analysis by ANSYS10.0 program was conducted and the results between test and analysis are close. Numerical simulation shows that overall failure features of PPCCB with appropriate reinforcement are basically the same as that of cast-in-situ beam. For the composite beams with natural rough surface, it becomes feasible to analyze without considering the behavior of interface slip.

Zhou X.,Hunan University | Zhou X.,Lanzhou University | Chen W.,Hunan University | Wu F.,Hunan University | And 2 more authors.
Jianzhu Jiegou Xuebao/Journal of Building Structures | Year: 2011

In response to the problem that the calculation results for the stiffness and deformation of the assembled monolithic concrete hollow floor with two-way ribs are not accurate enough, this paper made a study on the static load tests of three slab elements, which were a cast-in-situ concrete hollow slab element with two-way ribs, an assembled monolithic slab element and a ribbed beams slab element. The test results indicate that the prefabricated top and side plates of the hollow box have a good bond with cast-in-situ concrete ribs. The roof and floor can make an obvious contribution to the stiffness of the slab element. The mechanical performance of the cast-in-situ concrete hollow slab element with two-way ribs is similar to that of the assembled monolithic slab element. The phenomenon that the shear lag exists in the prefabricated monolithic top plate is confirmed according to the results of test and finite element analysis. A computational method considering the effect of prefabricated top and bottom plates was proposed for the calculation of sectional stiffness of floor slabs. The elastic stiffness and boundary support condition of the new type slabs were revised based on the look-up table method and intersecting beam method of the concrete waffle slabs. Then a new computational method for the calculation of stiffness and deformation which can yield more accurate and reasonable results was proposed. The calculation results of the test specimens using the proposed method agree well with the test results.

Wu F.-B.,Hunan University | Huang H.-L.,Hunan University | Huang H.-L.,Hunan Gaolin Construction Group Stock Ltd Company | Chen W.,Hunan University | And 2 more authors.
Tumu Jianzhu yu Huanjing Gongcheng/Journal of Civil, Architectural and Environmental Engineering | Year: 2011

For the convenience of industrialized production and site operation, specification design of PPCRP (precast prestressed concrete ribbed panels) is discussed. In order to obtain ultimate bearing capacity, bending rigidity and crack resistance, four PPCRP with two types of spans are studied, and the results show that PPCRP can satisfy the requirements of bearing capacity in construction phase and can serve as stay-in place formwork. To verify the mechanical property, shear behavior on contact interface of composite member and moment redistribution factor of continuous composite member, two single-span composite members and one two-span continuous composite member are studied. It is indicated that computational method for bearing capacity of composite member can be the same as cast-in-situ concrete slab. Besides, section strain analysis for composite member in two-loading is conducted, which suggests that thickness of bottom board can be used as calculated height with the consideration of two-loading.

Discover hidden collaborations