基于Matlab绘制剪切力和弯曲矩图

%% Shear Force & Bending Moment Examples%     This program calculates the shear force and bending moment profiles, %     draws the free body, shear force and bending moment diagrams of the %     problem.% %     Under the free body diagram, the equations of each section is clearly %     written with Latex% %% How to call the function%     To use this program, you need to call the solve function on the instance %     of the SFBMProb object that has the complete problem description.%     You first create the SFBMProb Object and then add the loads in no%     partcular order. % %% How to create the SFBMProb object%     create an instance of SFBMProb by calling "SFBMProb" with three%     arguments. The first is the name of the problem. For instance, %     "Example 1", the second argument is Length of the beam, and the third%     is locations of the supports. %%     prob = SFBMProb(name, length, supports)%%-   Cantilever%       If the problem is a cantilever problem, then you have only one clamped %       support, at the beginning or end of the beam. In such a case, the number is%       second argument contains 2 elements instead of three. %%       For instance, for a cantilever of length 20m, supported at the beginning, %       prob = SFBMProb("Cantilever", 20, 0)%       and if supported at the end, %       prob = SFBMProb("Cantilever", 20, 20)%%-   Beam on the floor%       Its possible to have a problem in which the body is lying on the floor %       without any point support. In such scenario, %       prob = SFBMProb("BeamOnFloor", 20, [])%%% Set Units%     We have just two primary physical quantities here: Force and Legnth.%     ForceUnit default is KN%     LengthUnit default is m%     but to set a preferred unit, use%%     prob.ForceUnit = "lb";%     prob.LengthUnit = "inch";%% Load Description%     Loads can be Force: such point or distributed load, or Torque the we%     call Moment here. In general Load would have value and location.%     The sign of the value can indicate whether it is pointing upwards, or%     downwards in the case of force, or clockwise/anticlockwise in case of%     moment. While moment and point load have scalars for value and%     location, distributed load have vector of value and location. %% How to add loads to the object.%%%-   Moment(Torque)%         To add a clockwise moment of magnitude 3KN-m applied at point 5m%         prob.AddMomentLoad(-3, 5);%         For an anticlockwise moment of magnitude 7KN-m applied at point 8m%         prob.AddMomentLoad(7, 8);%%%-   Concentrated Load(Force)%         To add a downward point load of magnitude 0.8KN applied at point 3m%         prob.AddPointLoad(-0.8, 3);%         For an upward point load of magnitude 5KN-m applied at point 7m%         prob.AddMomentLoad(5, 7);%%%-   Distributed Force%         To add uniform upward distributed load of magnitude 2KN/m applied from point 3 to 5m %         prob.AddDistLoad([2, 2], [3, 5]);%         For linearly increasing distributed load 2KN/m  to 5KN/m applied from point 3 to 5m %         prob.AddDistLoad([2, 5], [3, 5]);%%     Example(1)%Problem NameName = 'Example 1';%Length and SupportsLength = 10; Supports = [2, 10]; % length  = 10, supports at 2 and 10;prob = SFBMProb(Name, Length, Supports);%Set Unitprob.ForceUnit = 'lb';prob.LengthUnit = 'inch';%Concetrated Loadsprob.AddPointLoad(-5, 0); % 5N downward at point 0prob.AddPointLoad(-10, 8); % 10N downward at point 8%Torquesprob.AddMoment(10, 3);  % ACW 10Nm at point 3prob.AddMoment(-10, 7); % CW 10Nm at point 7%Solve the problemprob.Solve()%%     Example(2)%Problem NameName = 'Example 2';%Length and SupportsLength = 20; Supports = 0; % length  = 20m, Cantilever supported at 0 m;prob = SFBMProb(Name, Length, Supports);%Concentrated Loadsprob.AddPointLoad(-5, 6);   % 5N downward at point 6prob.AddPointLoad(-10, 13); % 10N downward at point 13%Distributed Loadsprob.AddDistLoad([5,5],[1,3]);    % Constant 5N/m upwards from 1m to 3 m prob.AddDistLoad([-4,-4],[14,17]); % Constant 4N/m downwards from 14m to 17 m%Solve the problemprob.Solve()%%     Example(3)%Problem NameName = 'Example 3';% Length and SupportsLength = 30; Supports = [0,20]; % length  = 30m, supports at 0m and 20m;prob = SFBMProb(Name, Length, Supports);% Concentrated Loadsprob.AddPointLoad(-20, 6);   % 20N downward at point 6prob.AddPointLoad(-10, 13);  % 10N downward at point 13prob.AddPointLoad(5, 27);    % 5N upward at point 27% Torquesprob.AddMoment(50, 8);  % ACW 50Nm at point 8prob.AddMoment(-45, 25); % CW 45Nm at point 25% Distributed Loadsprob.AddDistLoad([7, 7], [1,3]);    % Constant 7N/m upwards from 1m to 3m prob.AddDistLoad([-5,-5], [12,18]); % Constant 5N/m downwards from 12m to 18m% Solve the problemprob.Solve()%%     Example(4)%Problem NameName = 'Example 4';% Length and SupportsLength = 20; Supports = [5,20]; % length  = 20m, supports at 5m and 20m;prob = SFBMProb(Name, Length, Supports);% Concentrated Loadsprob.AddPointLoad(-2, 0);   % 2N downward at point 0% Torquesprob.AddMoment(50, 8);  % ACW 50Nm at point 8prob.AddMoment(-45, 15); % CW 45Nm at point 15% Distributed Loadsprob.AddDistLoad([5, 5], [1,3]);    % Constant 7N/m upwards from 1m to 3m prob.AddDistLoad([-4, -4], [14, 17]); % Constant 5N/m downwards from 12m to 18m% Solve the problemprob.Solve()%%     Example(4)%Problem NameName = 'Example 4';% Length and SupportsLength = 20; Supports = [6,20]; % length  = 20m, supports at 5m and 20m;prob = SFBMProb(Name, Length, Supports);% Concetrated Loadsprob.AddPointLoad(-2,0);  % 2N downward at point 0% Torquesprob.AddMoment(10,8);   % ACW 10Nm at point 8prob.AddMoment(-15,12); % CW 10Nm at point 12% Distributed Loadsprob.AddDistLoad([5, 2, 5], [1, 3, 5]);    % Quadratic profile distributed upwards force from 1m to 5m and prob.AddDistLoad([-4, -2, -4],[14, 16, 18]); % Quadratic profile distributed downwards force from 14m to 18m% Solve the problemprob.Solve()%%     Example(5)%Problem NameName = 'Example 5';% Length and SupportsLength = 20; Supports = [6,20]; % length  = 20m, supports at 5m and 20m;prob = SFBMProb(Name, Length, Supports);% Concetrated Loadsprob.AddPointLoad(-2,0);  % 2N downward at point 0% Torquesprob.AddMoment(10,8);   % ACW 10Nm at point 8prob.AddMoment(-15,12); % CW 10Nm at point 12% Distributed Loadsprob.AddDistLoad([5, 2], [1, 3]);    % Linear profile upwards from 1m to 3m and prob.AddDistLoad([2, 5], [3, 5]);    % Linear profile upwards from 3m to 5m and prob.AddDistLoad([-4, -2],[14, 16]); % Linear profile downwards from 14m to 16mprob.AddDistLoad([-2, -4],[16, 18]); % Linear profile downwards from 16m to 18m% Solve the problemprob.Solve()%%     Example(6)%Problem NameName = 'Wikipedia';Length = 50; Supports = 50;prob = SFBMProb(Name, Length, Supports);prob.Source = "https://en.wikipedia.org/wiki/Shear_and_moment_diagram#Calculating_shear_force_and_bending_moment";%Set Unitsprob.ForceUnit = 'k';prob.LengthUnit = 'ft';% Concetrated Loadsprob.AddPointLoad(-10,0); prob.AddPointLoad(25.3,10); prob.AddPointLoad(-3.5,25); % Torquesprob.AddMoment(-50,37.5); % Distributed Loadsprob.AddDistLoad([-1,-1], [10,25]);  % Solve the problemprob.Solve()