Joint Rotations and End Moments for a Continuous Beam
This program will compute the joint rotations and the member end-moments ofa continuous beam subjected to generalloading.

The various program options include:

1. Column specifications

* .Number of columns

.* Columns of the same height

.* Columns of differing heights

2. Cross section elements

.* Constant cross section elements

.* Variable cross section elements

For variable cross section beams, the stiffness matrix should be such that:

In the case of variable cross section columns, the' A' member end corresponds to that connected to

the beam joint.

Program Notes

This program is designed to handle systems with up to 10 joints. This can be modified by changing the
DIM statements as follows:

DIM L(N), Kl(N), K2(N), K3(N)

DIM Ql (N), Q2(N)

DIM A(N), B(N), C(N), D(N)

where N is the maximum number of joints.

Example

Compute the bending moment at point 2 of the continuous beam for the two load cases shown:

Downloads:

Basic program - liberty basic - lbjremcb.bas

Test Case:

JOINT ROTATIONS AND END MOMENTS FOR ACONTINUOUS BEAM

***STRUCTURE DEFINITION***
NUMBER OF SPANS = 2

TYPE OF STRUCTURE
1: NO COLUMNS
2: EQUAL HEIGTH COLS.
3: DIFF'T HEIGTH COLS.

TYPE = 1

MEMBER TYPE
1: CONSTANT CROSS SECT.
2: VARIABLE CROSS SECT.

TYPE = 1

ELASTIC MODULUS =1

***BEAM GEOMETRY***
> SPAN 1
LENGTH = 10
MOMENT OF INERTIA = 1

> SPAN 2
LENGTH = 15
MOMENT OF INERTIA = 2

***L0AD SPECIFICATION***
L0ADCASE 1
ANY JOINT L0ADS (Y/N) ?N
ANY SPAN L0ADS (Y/N) ?Y

***SPAN L0ADS***
> SPAN 1
DISTRIBUTED L0AD = 1
NUMBER OF POINT L0ADS = 0
> SPAN 2
DISTRIBUTED L0AD = 3
NUMBER OF POINT L0ADS = 0

SOLUTION FOR L0AD CASE 1
**************************
***JOINT ROTATIONS***
JOINT 1 ROT= -30.5059524
JOINT 2 ROT= 102.678571
JOINT 3 ROT= -156.808036

***MEMBER FORCES-**
> SPAN 1
LEFT MOMENT= 0
RIGHT MOMENT= 43.3035714
> SPAN 2
LEFT MOMENT= -43.3035714
RIGHT MOMENT= 0

MORE L0AD CASES? (Y/N) N


***ANALYSIS COMPLETE***