# A Review of the T-Stub Components for the Analysis of Bolted Moment Joints
## 3 Experimental Testing
In 1976, [PERSON] [31] proposed an analytical method, see Figure 18a, to determine the yield force and the bolt force for T-connections and end plate connections. This method takes into consideration the effect of the prying force, which increases the bolt force. Therefore, [PERSON] performed four experimental tests on welded T-connections and fifteen tests on beam-to-beam end plate connections to validate this theory. The experimental tests showed that the mechanism model that considered the formation of plastic hinges at the fillet toe and the bolt line were unlikely to appear. This mechanism model was taken into account by [PERSON], [PERSON], [PERSON], etc. Furthermore, this research work clarified that end plate bolted connection could be designed as a T-connection and two different manners of calculate the conventional bolt length \(L_{b}\), see Figure 18b, for snug-tightened bolts and for preloaded bolts (bolt stiffness). In 1977, [PERSON] and [PERSON] [32] idealized the tension zone of the extended end plate beam and the column flange as an isolated T-stub. The failure mode was studied according to the yield line method, but they allowed curved yield boundaries, which accurately predicted the flexural yield loads in unstiffened and normally stiffened connection. They defined the failure modes by three mechanisms: Mechanism A (EC Failure mode 3), Mechanism B (EC Failure mode 2) and Mechanism C (EC Failure mode 1). In 1983, [PERSON] continued his research on end-plate moment connections and published a proposal for the standardization of the design formulas of extended end-plate connection [33], which are based on the results of experimental tests. This standardization concluded that connections with extended end plates develop enough rotation capacity for plastic design of a beam if the connection is design according to the plastic design formulas of the standardization (see the Table 3.2 of [33]), the beam-span is limited to 30 times the beam depth and the beam span is limited to 16 m.  
In 1998, [PERSON] et al. [34] studied the influence of bolt preloading on T-stubs. These T-stubs were obtained from laminated profile HEA and HEB, steel grade Fe430, and were connected by high strength bolts 10.9 with diameter of 20 mm (six specimens) and 12 mm (10 specimens). The bolt preloading was applied in three different levels: the first level was snug tight, the second level corresponded to 40% (275 Nm) of the bolt yield stress, for diameter of 20 mm, and to a 60% of the bolt yield stress (85 Nm), for a diameter of 12 mm. The third level corresponded to an 80% of the bolt yield resistance equal to 550 Nm and 113 Nm for bolt diameter 20 mm and 12 mm, respectively. It was observed that the bolt preloading significantly affects the stiffness of bolted joints. Moreover, the reliability of predicting the T-stub stiffness was studied by the component method (non-preloaded and preloaded). In 1999, [PERSON] described 48 T-stub tests in [35]. These experimental tests were performed to develop design rules for T-stub connections which would result in a full  
Figure 18: (**a**) Analytical model of connection; (**b**) Model of conventional bolt length [31]. strength connection, ductile behaviour, and connection stiffness. In this research [PERSON] was focused to study the T-stub component, see Figure 19, subject to tensile static load (studied by [PERSON] and [PERSON], and [PERSON]), and cycle loads. The results about the comparison between monotonically tested T-stubs and cyclically tested T-stubs showed that the monotonic test data provided an accurate envelope of the cycle results. In 2001, [PERSON] et al. [36] presented the results of an experimental program that was devoted to validating a theoretical model, which was proposed in a previous investigation [37]. The experimental program tested 12 T-stub to evaluate the plastic supply.