Fig 1.
Structure diagram of the UT-type prefabricated joint.
Fig 2.
Installation process.
Fig 3.
Field configuration of the structural testing setup.
Fig 4.
Geometric dimensions of UT-type joint test specimens (Unit: mm).
Table 1.
Joint number and corresponding working conditions.
Table 2.
Mechanical properties of steel materials.
Fig 5.
Loading moment-angle curve in static testing (0.2 μ).
Fig 6.
Loading moment-angle curve in static testing (0.4 μ).
Fig 7.
Loading moment-angle curve in static testing (0.6 μ).
Fig 8.
Positive bending moment loading failure diagram (No axial force).
Fig 9.
Negative bending moment loading failure diagram (No axial force).
Fig 10.
Failure mechanism diagram under coupled axial tension and positive moment ().
Fig 11.
Failure mechanism diagram under coupled axial tension and negative moment ().
Fig 12.
Failure mechanism diagram under coupled axial compression and positive moment ().
Fig 13.
Failure mechanism diagram under coupled axial compression and negative moment ().
Fig 14.
UT-type joint finite element model.
Fig 15.
UT-type joint specimen under cyclic loading.
Fig 16.
Cyclic loading system.
Fig 17.
U5-D5 hysteresis curve.
Fig 18.
U4-D5 hysteresis curve.
Fig 19.
U4-D4 hysteresis curve.
Fig 20.
Difference of characteristic points in hysteretic curves under axial force.
Fig 21.
Average stiffness difference of each joint under axial force.
Fig 22.
Difference in average energy dissipation coefficient of each joint under axial force.
Fig 23.
Fitted skeleton curve.
Fig 24.
Restoring force model of UT-type joint.
Table 3.
Characteristic values of UT-type joint force performance.
Table 4.
Characteristic values of UT-type joint force performance by simulation.
Table 5.
UT-type joint numbers for cyclic loading.
Table 6.
Characteristic points of hysteretic curves of each joint without axial force.
Table 7.
The average stiffness of each joint under each level of loading without axial force.
Table 8.
Average energy dissipation factor of each joint under cyclic loading.
Table 9.
Fitting equation of skeleton curve.
Table 10.
Stiffness degradation equation of each stage.
Fig 25.
Stress distribution under axial tension (0.3 μ) in elastic stage.
Fig 26.
Stress distribution under axial compression (0.3 μ) in elastic stage.
Fig 27.
Ratio of yield rotation under axial force (Obverse loading).
Fig 28.
Ratio of yield rotation under axial force (Reverse loading).
Table 11.
Stiffness of joint skeleton curve in elastic-plastic stage under influence of axial force.
Fig 29.
Bending moment difference ratio ((Mui-Mu)/Mu) influenced by axial force.
Table 12.
Energy dissipation coefficients of restoring force model.
Fig 30.
Restoring force model of joints without axial force effect (U5-D5 as an example).
Fig 31.
Restoring force model of joints under axial compression (U5-D5-C-k0.1 as an example).
Fig 32.
Restoring force model of joints under axial tensile (U5-D5-T-k0.1 as an example).