Tuesday, April 21, 2009

Subframe/ Continuous Beam using Excel

This the sample page of the continuous spreadsheet program that I developed. The input is simple and straight forward. The beauty of using spreadsheet is that even if the input is enter incorrectly first time, you could amend it later without going through the entire input process. Output forces are directly printed beside each spans.

The are two buttons command, namely "Span Information" & :Input Load Type". This is where all the macro will be invoked.

Input : 1) By clicking the macro, the input screen would ask for number of span, support conditions, beams span lengths, beam and column sizes in a sequential way.

2) Next step is to invoke the Input Load Type macro.

3) You can input maximum 10 load cases for each spans. Uniformly distributed load, triangular load, point load, trapezoidal load and linear load are all the load cases.

4) No analysis step is needed as analysis will be completed the moment the last load case is completed.

5) The support reactions for Dead Load, Live Load and ultimate load & column moment will also be computed and shown in the spreadsheet.

Next post, I will illustrated the Subframe analysis spreadsheet usingn OpenOffice.

Monday, April 20, 2009

Develop spreadsheet program for Structural Analysis & Design

Over the years, I have developed a comprehensive suite of spreadsheet programs that can carry out reinforced concrete & steel structure analysis and design. The programs generally are in accordance to British Code BS8110 (1985, 1997) and BS5950 (2000). Some of the programs are also available in CSA A23.3-04 code. At the same time, I am also developing all of programs into Canadian RC code CSA A23.3-04 as I intend to move to Vancouver and hopefully can land a job as a structural engineer there.

If you find my spreadsheet programs relevant, you could help me by introducing my blogs to the Canadian engineering consulting firms. In the future few blogs, I will paste some of the screen shots of my programs. If you find my programs relevant and useful, please give me your comment. I would like to improve on them. If you are from the Canadian Civil and Structural Consulting community, I would appreciate you could recommend my blogs to them. It will help me to find job opportunity in the future.

In the next few blogs, I will give a list of the analysis and design programs that I developed and also how to use it. Screenshots of the programs will also be posted for viewers to understand the programs.

My spreadsheet programs were written from the perspective as a practicing engineer. They follow the sequence of design steps and output the results at important checks as per code requirements. Instead of the commercial programs that work like a black box, my programs will allow users to amend the formula so that each user can customize to their needs. At the sametime, some of the spreadsheet programs in the market can be to very detailed in the design calculation (which become too cumbersome to read), I output the key steps and results for manual checking, leaving the routine calculations hidden so that submisson become concise, simple and neat.
In the next few posts, you will find my programs as I explained further.

Some of the programs are :

1) Continuous &Subframe Analysis and Design (Excel & Calc) - This program analyses and design continuous beams or subframe using moment distribution methods. Moments and shear forces envelope are based on BS8110 requirements but the programs can analyse more rigorous loading patterns if needed. The maximum number of span is 10 and can carry out analysis on cantilever ends, fixed ends etc. Excel macro is added to the programs to ease the input of spans and loadings. However, the programs can still work if the macro is disable, it will only be a more cumbersome input steps only. The program had been tested rigirously with commercial software such as SAP2000, Prokon Continuous Beams, TopCad Beam and some textbooks examples. All the results tally exactly.

The program is also writtten in OpenOffice and run perfectly well. In future post, I will denote as (Excel & Calc) for Microsoft Excel format and OpenOffice Calc format.

The design module is an add-on and can be carried out separately from the analysis portion. Currently the design is in BS8110 (1985, 1997). CSA A23.3-04 code is currently implementing.

2) Reinforced Concrete Section Analysis (Rectangular Beams, Rectangular and Circular Column) - (Excel & Calc) Every engineer writes a program to design moment and shear for RC sections once in their work life. I developed more than section design. This is a capacity check of rectangular beam and column and circular column. The analysis is carried out using first principle and reinforcement arrangement can be asymmetric. Macro is written to accelerate the iteration process but without the macro, the program will still work.

Currently, the program is written in both BS8110 and CSA A23.3-04.

3) Beam Design (Excel & Calc) - Design the reinforcement requirements of beam section for bending moment, shear force and torsional force. This is a typical beam design program that is used on daily basis.

The program can design in both BS8110 and CSA A23.3-04.

4) Pilecap Design (Excel & Calc) - Design of pilecap for pilegroup of 2 to 6 piles. The pile arrangement need to be regular in order for the program to work.

5) Box Drain Design (Excel & Calc) - Design of box culvert using coefficient given in Reynold Handbook. The program was tested using SAP2000 plane frame with numerous load patterns and cases. Results proved to be exactly.

6) Retaining wall Design (Excel & Calc) - Design of L shape retaining walls and checking of factor of safety for sliding, overturning and bearing pressure. The soil can be on the heel or toe of the retaining walls making the program very versatile to use.

7) Corbel Design and Deep Beam Design (Excel & Calc - Design corbel and deep beam using strut and tie model.

8) One way and Two Way spanning slab analysis and design (Excel & Calc)

9) Pile Penetration Design (Excel & Calc) - The concept of the pile design varies between different countries and regions. In this part of the world, the concept of Meyerhoff Method is used. The method depends on the SPT values to calculate the skin friction and endbearing capacity. The results have been proven to be reliable as instrumented load tests carried out in the pass 15 years in most project had correlate reasonably well.

10) Steel section design (Excel & Calc) - the program can check the capacity of the steel UB & UC subjected to biaxial bending, axial force and shear.

11) Street Strut Design (Excel & Calc) - The program is use for the design of temporary steel strut to support sheetpile walls, Diaphragm wall and Contiguous Bored Pile wall. It had also taken into account of one-strut failure scenario with reduce factor of safety.

12) Composite Steel Column Design to EC4 (Excel & Calc) - The program can calculate the capacities of concrete encased rectangular and circular steel UB & UC and concrete filled hollow section.

13) Pad footing design (Excel & Calc)- generally a single columns pad design program

14) Eccentricities of piles in a group checking (Excel & Calc) - After pile installation, the eccentricites of piles during installation will create eccentricities in the pilegroup. The program check the group eccentricities for both symmetric and asymmetric pile arrangement.

15) Underground water sump capacities check and surface drain size calculation

There are still many programs that I have not listed out. I the next blog, I will have some of the screenshots to share.