Fatigue behaviour of composite girders with concrete-filled tubular flanges and corrugated webs—experimental study

Zhou²,

et al. 2023

Materials

The efficient crack eliminated stop-hole measure was proposed to repair and reduce the stress concentration associated fracture risk of the corrugated plate girders by setting it at the critical joint of flange plate with tightened bolts and gaskets under preloading. To investigate the fracture behaviour of these repaired girders, parametric finite element analysis was conducted, focusing on the mechanical feature and stress intensity factor of crack stop-hole in this paper. The numerical model was verified against experimental results first, and then the stress characteristics due to the presence of crack open-hole were analysed. It was found that the moderate-sized open-hole was more effective than the over-sized open-hole in the reduction of stress concentration. For the model with prestressed crack stop-hole through bolt preloading, the stress concentration was nearly 50% with the prestress around open-hole increased to 46 MPa, but such a reduction is inconspicuous for even higher prestress. Relatively high circumferential stress gradients and the crack open angle of oversized crack stop-holes were decreased owing to additional prestress effects from the gasket. Finally, the shift from the original tensile area around the edge of the crack open-hole that was prone to fatigue cracking to a compression-oriented area is beneficial for the reduction of stress intensity factor of the prestressed crack stop-holes. It was also demonstrated that the enlargement of crack open-hole has limited influence on the reduction of stress intensity factor and crack propagation. In contrast, higher bolt prestress was more beneficial in consistently reducing the stress intensity factor of the model with the crack open-hole, even containing long crack.

where e is the eccentricity between the centre of the crack and the centreline of the flange while it can be deduced as 0.5 b l sin θ c .…”

Section: Resultsmentioning

confidence: 99%

Section: Numerical Verificationmentioning

confidence: 99%

Numerical Analysis of Fracture Behaviour for Cracked Joints in Corrugated Plate Girders Repaired by Stop-Holes

Zhou²,

et al. 2023

Materials

“…The shape of the border components has a considerable impact on the structure's quasi-static behaviour [14]. Fatigue crack initiation is correctly accounted for at the top surface of the bottom tubular flange, where longitudinal stress accumulates at the welded toes towards the end of the inclined fold adjoining longitudinal fold of the corrugation [15], [16]. Very stiff springs are used to mimic the geometric limitations of the folded plates, such as the conditions at the ends and intermediate supports [17]- [22].…”

Section: Introductionmentioning

confidence: 99%

Experimental Investigation on Behaviour of Folded Plate

Dhanabal¹,

Reddy

Sushmitha

2023

J. Mod. Mater.

Persistence of research was towards the behaviour of folded plate. In this project, we used GGBS blended ferrocement concrete to cover a folded plate 600 mm x 1800 mm x 150 mm. Ferro cement is a building material that is emerging as an alternative for traditional RCC. According to prior research, folded plates are the most cost-effective and visually acceptable option for longer span roofs. First, we built the folded plate model in ANSYS and investigated its behaviour in terms of load versus deflection. Later, for experimental purposes, we cast a folded plate coated with GGBS mixed ferrocement concrete. The results of the experimental inquiry demonstrate that there was an improvement in flexural behaviour when compared to the traditional model. The same was verified using ANSYS findings. ANSYS analysis aids in comparing and summarising experimental data. Both the analytical and experimental inquiry results show that ferro cement structures are a good alternative to RCC since they are less costly and lighter. Because folded plates retain their effectiveness for a longer length of time when Ferro cement is utilised. Ferro cement has made the components smaller to support the load because ferro cement parts are high in stress when reinforcement is spread.

“…Accordingly, fatigue cracks usually originate in the joint between the CSWs and the top slab [ 12 , 13 , 14 ]. To predict the potential fatigue failure of composite beams with CSWs, calculation methods for the fatigue life have been investigated by many researchers as well [ 15 , 16 , 17 ].…”

Section: Introductionmentioning

confidence: 99%

Fatigue Behaviors of Joints between Steel Girders with Corrugated Webs and Top RC Slabs under Transverse Bending Moments

et al. 2023

Steel–concrete composite box beams are widely used in bridge engineering, which might bear transverse and longitudinal bending moments simultaneously under vehicle loads. To investigate the fatigue performance of joints between the steel girders and the top reinforced concrete (RC) slabs under transverse bending moments, a reduced scale joint between the weathering steel girder with the corrugated steel web (CSW) and the top RC slab was designed and tested under constant amplitude fatigue loads. Test results show that the joint initially cracked in the weld metal connecting the CSW with the bottom girder flange during the fatigue loading process. The initial crack propagated from the longitudinal fold to the adjacent inclined folds after the specimen was subjected to 7.63 × 105 loading cycles and caused the final fatigue failure. Compared with the calculated fatigue lives in the methods recommended by EC3 and AASHTO, the fatigue performance of the details involved in the joint satisfied the demands of fatigue design. Meanwhile, finite element (FE) models of joints with different parameters were established to determine their effect on the stress ranges at the hot spot regions of the joints. Numerical results show that improving the bending radius or the thickness of the CSW helps to reduce the stress ranges in the hot spot regions, which is beneficial to enhance the fatigue resistance of the investigated fatigue details accordingly.