Most　of　the　accidents　related　to　concrete　formwork　are　triggered　by　improper　construction　operations　and　the　unsound　lateral　pressure　estimations　detailed　in　concrete　formwork　specifications.　In　this　study　a　series　of　experiments　was　conducted　to　reveal　the　effect　of　different　factors　on　lateral　pressure.　The　results　show　that　concrete　slump,　casting　speed,　and　vibration　mode　can　greatly　influence　the　pressure;　and　the　data　obtained　in　the　experiments　differ　greatly　from　the　values　yielded　by　different　specifications.　A　modification　is　proposed　to　the　GB50666　specification　in　order　to　improve　the　accuracy　and　reliability　of　pressure　estimations.　(C)　2016　Elsevier　Ltd.　All　rights　reserved.