Is you question whether or not the current equations and limitations noted in ACI 347-04, Formwork for Concrete, are validated by direct experimental or field results?
Or is your question, where can you find an equation to approximate lateral pressure due to placing concrete in a column or wall form?
For the second question, as noted above, the equations can be found in ACI (American Concrete Institute) documents 347-04 (Current revision, changed from 347-01) and SP-4, Guide to Formwork for Concrete, which includes ACI 347-04 as an appendix in the current printing, which I believe is the seventh edition.
If you question is to the validity of the equations and chemistry coefficients, my personal experience without instrumentation has found good results with more than acceptable finish when following the equations to determine a pour pressure and less than desireable results, with significant pillowing of the facing materials and increased form failures when the equations are not followed.
With regard to studies and instrumented forms, in place testing has been done by one of my companies competitors which indicates a strong correlation to the recommended equations and serves to validate their use in my work.
Please reply if further clarification can be provided.
From somewhere else... the spreadsheets are extremely well done. It takes a little searching on the concrete.org website, though.
Dik
Lateral pressure calculations are also performed in the spreadsheet program made available to ACI by William C. Epstein, professor of construction management at California State Polytechnic University, San Luis Obispo. To use the spreadsheets, go to
