34、结构模型与解决方案的Python实现

结构模型与解决方案的Python实现

1. 结构模型基础类

1.1 杆类（StrBar）

杆类用于表示结构中的杆，其定义如下：

_id: int,
start_node: StrNode,
end_node: StrNode,
cross_section: float,
young_mod: float
):
self.id = _id
self.start_node = start_node
self.end_node = end_node
self.cross_section = cross_section
self.young_mod = young_mod
@property
def geometry(self):
    return Segment(
        self.start_node.position,
        self.end_node.position
    )
@property
def length(self):
    return self.geometry.length
def global_stiffness_matrix(self) -> Matrix:
    direction = self.geometry.direction_vector
    eal = self.young_mod * self.cross_section / self.length
    c = direction.cosine
    s = direction.sine
    c2_eal = (c ** 2) * eal
    s2_eal = (s ** 2)