Experimental on tensile performance of roadbridgelink slab of jointless bridges(PDF)
长安大学学报（自然科学版）[ISSN:1006-6977/CN:61-1281/TN]
- Issue:
- 2022年2期
- Page:
- 68-78
- Research Field:
- 桥梁与隧道工程
- Publishing date:
Info
- Title:
- Experimental on tensile performance of roadbridgelink slab of jointless bridges
- Author(s):
- ZHAN Xuefang; WANG Xian; LIU Kaile; LEI Jian; HU Yujie
- School of Civil Engineering, Central South University of Forestry and Technology,Changsha 410004, Hunan, China
- Keywords:
- bridge engineering; tensile deformation performance; experiment; SHCC roadbridge link slab; jointless bridge; crack width; crack spacing; trilinear constitutive model
- PACS:
- -
- DOI:
- -
- Abstract:
- To study the mechanical properties of SHCC (strain hardening cementitious composites) roadbridge link slab for jointless bridge, especially its tensile deformation capacity under temperature load. The equivalent temperature deformation was used to simulate the temperature load, and the tensile performance of SHCC roadbridge link slab under temperature drop were studied by means of theoretical, experimental and numerical analysis. Firstly，the calculation formula of internal force and deformation of SHCC roadbridge link slab under temperature drop was derived and the conditions of using the formula were limited. Secondly, the tensile test of two groups of dumbbells shaped SHCC specimens with different components were test and the constitutive models were derived. The indoor SHCC slab model was carried out, and the sliding friction factor at the bottom of SHCC plate was measured. The stress mechanism, crack distribution law and the ability of absorbing and transferring deformation of SHCC roadbridge link slab were revealed. Finally, the stressstrain relationship of SHCC material was simulated by using trilinear constitutive model, the tensile performance of SHCC roadbridge link slab under temperature drop was established by finite software (ABAQUS), and the tensile performance of SHCC slab under temperature drop was analyzed. The results show that the initial crack stress of SHCC specimen with mix proportion 1 is 2 MPa, and the ultimate strain is 4.3%, which meets the demand of the tensile deformation capacity of the full jointless bridge link slab. When the longitudinal deformation reaches 10 mm, there are nearly 154 micro cracks on the surface of SHCC slab, the crack spacing is small (2 to 10 cm), and the crack width is controlled within 80 μm. At the same time, the internal stress of tension end plate is 2.8 MPa, and the anchoring force of anchorage end is 196.6 kN. After unloading, the cracks closed, no fibers is pulled out or broken. This strong deformation absorbing ability of SHCC roadbridge link slab is verified, which fully meets the deformation and stress requirements of full jointless bridge. The load displacement curve of the finite element analysis is basically consistent with the measured value, which proved that the trilinear constitutive model of SHCC material used in numerical model analysis is safe. The theoretical support for the design and implementation of fully jointless SHCC roadbridge link slab are provided by the research results. 6 tabs, 9 figs, 29 refs.
Last Update: 2022-04-13