.Net ( c# ) 与 Fortran 混合编程实例（二）：杆系结构有限元法——平面桁架解答(2)

第二节  桁架结构基本信息录入与保存

此节之后会结合一个算例。结构如图，EA = 300000 kN

杆件编号、节点编号、坐标系：

2.1  文本信息

bars.txt

1,1,3,300000
2,2,3,300000
3,4,3,300000
4,2,4,300000

nodes.txt

1,0,3,1,1,0,0
2,0,0,1,1,0,0
3,4,3,0,0,0,-20
4,4,0,0,0,30,0

2.2  静态类 ClassBasicInfo 存放基本结构数据

新建类库，命名为 Business，添加对 PlaceUsingTxt.dll 的引用，新建类，命名为 ClassBasicInfo，贴入以下代码：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace Business
{
    public static class ClassBasicInfo
    {
        public static int[,] BarsNodes;//杆件节点编号
        public static Single[] LinearStiffness;//杆件刚度

        public static Single[,] Coordinate;//节点坐标
        public static bool[,] Restraint;//节点约束
        public static Single[,] Loads;//节点荷载

        public static Single[,] TatalStiffnessMatrix;//总刚度矩阵
        public static Single[] TatalDisplacement;//总位移列阵
        public static Single[] TatalLoads;//总荷载列阵
        public static bool[] TatalRestraint;//总边界条件
    }
}

2.3  对静态类赋值

新建类，命名为 ClassGetBasicInfo，贴入以下代码：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

using PlaceUsingTxt;

namespace Business
{
    public class ClassGetBasicInfo
    {
        public int NumBars;//杆件数
        public int NumNodes;//节点数

        public void InitBars(string StrBars)
        {
            //初始化杆件信息
            ClassReadTxt crt = new ClassReadTxt(StrBars);
            string[,] tempstr = crt.OutStr2D();
            crt.close();

            //取得杆件数
            NumBars = tempstr.GetLength(0);

            ClassBasicInfo.BarsNodes = new int[NumBars, 2];
            ClassBasicInfo.LinearStiffness = new Single[NumBars];

            for (int i = 0; i < NumBars; i++)
            {
                ClassBasicInfo.BarsNodes[i, 0] = Convert.ToInt32(tempstr[i, 1]);//杆件起点编号
                ClassBasicInfo.BarsNodes[i, 1] = Convert.ToInt32(tempstr[i, 2]);//杆件终点编号
                ClassBasicInfo.LinearStiffness[i] = Convert.ToSingle(tempstr[i, 3]);//杆件刚度
            }

        }

        public void InitNodes(string StrNodes)
        {
            //初始化节点信息
            ClassReadTxt crt2 = new ClassReadTxt(StrNodes);
            string[,] temps = crt2.OutStr2D();
            crt2.close();

            //取得节点数
            NumNodes = temps.GetLength(0);

            ClassBasicInfo.Coordinate = new Single[NumNodes, 2];
            ClassBasicInfo.Restraint = new bool[NumNodes, 2];
            ClassBasicInfo.Loads = new Single[NumNodes, 2];

            for (int i = 0; i < NumNodes; i++)
            {
                ClassBasicInfo.Coordinate[i, 0] = Convert.ToSingle(temps[i, 1]);//节点x坐标
                ClassBasicInfo.Coordinate[i, 1] = Convert.ToSingle(temps[i, 2]);//节点y坐标
                ClassBasicInfo.Restraint[i, 0] = Convert.ToBoolean(Convert.ToInt32(temps[i, 3]));//节点x方向约束
                ClassBasicInfo.Restraint[i, 1] = Convert.ToBoolean(Convert.ToInt32(temps[i, 4]));//节点y方向约束
                ClassBasicInfo.Loads[i, 0] = Convert.ToSingle(temps[i, 5]);//节点x方向荷载
                ClassBasicInfo.Loads[i, 1] = Convert.ToSingle(temps[i, 6]);//节点y方向荷载
            }
        }

        //初始化有限元法基本方程矩阵
        public void InitMatrix()
        {
            ClassBasicInfo.TatalStiffnessMatrix = new Single[NumNodes * 2,NumNodes * 2];//总刚度矩阵
            ClassBasicInfo.TatalDisplacement = new Single[NumNodes * 2];//总位移列阵
            ClassBasicInfo.TatalLoads = new Single[NumNodes * 2];//总荷载列阵
            ClassBasicInfo.TatalRestraint = new bool[NumNodes * 2];//总边界条件
        }

        //接口
        public void Initialize(string StrBars,string StrNodes)
        {
            this.InitBars(StrBars);
            this.InitNodes(StrNodes);
            this.InitMatrix();
        }
    }
}

至此，完成基本信息的存放，以静态数组的方式储存，方便全局范围的访问。

其中，PlaceUsingTxt.dll 的源码参见：http://blog.csdn.net/silyvin/article/details/6758196