6.2.2 Bar elements

Bar elements，also called truss elements，are used to simulate struts，anchors，or other members bearing only axial stress，as shown in Figure 6.7.Each node of a bar element has only one degree of freedom.A bar element of low order has two nodes while one of high order has three nodes.In general excavation analyses，two node bar elements can achieve good accuracy.

Figure 6.7 Two⁃node bar element

Figure 6.8 Two⁃node beam element