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Editing Charts with the mouse
When editing chart ranges, to either change the limits of the range, or select a new column, I have been in the habit of either selecting a range and editing the text in the Formula Edit Bar, or right clicking, choose “select data”, and using the Select Data Dialog.
But there is an easier way:
Select a graph range and the data columns are highlighted:
The ranges can now be extended by simply dragging the corner to the required row:
The selected column can then be dragged across to another column:
Repeat for each data range:
and the job is done.
IP2 and IP2_py
The IP2 spreadsheet provides functions to calculate:
- Intersection points of 2D lines or polylines
- Intersection points of 2 circles, or a line and a circle
- Intersection circle of two spheres and intersection points of 3 spheres
- 3D centre point of a circle or arc
- Perpendicular distance from a point to a line or polyline.
- Maximum distance between any two points from a list
- Convert rectangular to polar coordinates and polar to rectangular
- Intersection point of 2 lines in 3D space
- Intersection of 2 planes and related functions
- Perspective projection of 3D lines
- One way and two way table interpolation
- Rotation between local and global coordinates, 2D and 3D
Since the last release:
- The IPSSS function (intersection of 3 spheres) has been corrected
- The py_Glob_to_Loc and py_Loc_to_Glob functions have been converted to Excel Python
- The file has been saved in two versions, one including the Python functions and the other VBA only.
The new version may be downloaded from IP2.zip (including full open source code).
The Python functions require Python and Numpy to be installed. Then simply copy the contents of the zip file to any convenient directory.
Reinforced Concrete Moment Curvature – Development over time
I recently noticed that in the RC Design Functions spreadsheet the TimeCurve function had stopped working. The function calculates the development of reinforced concrete section curvature over time, and was previously presented in Reinforced Concrete Moment-Curvature – 3; Restrained Shrinkage and Creep and Reinforced Concrete Moment-Curvature – 4; Development of curvature over time.
In the course of fixing the problem I took the opportunity to add some further refinements:
- The function previously did not allow for changes in the cracking stress over time, or for the effect of creep on the cracking strain. It now either calculates a cracking strain, which may include a proportion of the creep strain, or a cracking strain can be specified for each time step.
- The tension-stiffening factor calculation has been revised to take account of the effect of creep and shrinkage on the cracking moment.
- The output table has been rearranged and extended to include:
- The virtual prestress stress, as well as strain.
- The adjusted concrete elastic modulus.
- The cracking moment.
- The depth of the Neutral Axis
- The concrete stress at the top and bottom face
- The concrete strain including creep at the top and bottom face, and the cracking strain.
The updated spreadsheet (including full open-source code) may be downloaded from:
RC Design Functions spreadsheet
Examples of the function results, compared with experimental data, will be included in the next post on this subject. The screen-shots below show input and results for a typical beam loaded to just below the cracking moment, with cracking occurring as a result of the combined action of shrinkage and creep. Click any image for a full-size version:
Function input documentation:
Typical section properties input and output graph:
Time related data input:
Note that the function may be used anywhere in the spreadsheet. To display all the results it must be entered as an array function, using Ctrl-Shift-Enter. See Using Array Functions and UDFs for details.
Output results columns 1 to 9:
Output results columns 10 to 17:
Posted in Beam Bending, Concrete, Excel, Newton, UDFs, VBA
Tagged creep, development over time, Excel, moment curvature, RC Design Functions, Reinforced Concrete, shrinkage, TimeCurve function, UDF, VBA
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