What is Removal of Formwork The removal of formwork also called as strike-off of forms in which concrete is poured. The formwork should be removed only after when concrete component achieves its sufficient strength. The care should be taken during the removal of formwork to ensure the stability of the remaining formwork.
Factors Affecting Concrete Formwork Striking Times: The time of removal of formwork depends on how quickly concrete members gains its sufficient strength and it depends on the following factors. Grade of concrete – As the rich grade of concrete, the rate of development of strength is higher and thus concrete gain the strength in a shorter time. Grade of cement – a Higher grade of cement offers a quick setting and it gains strength in a shorter time. Type of Cement – Cement type used in concrete also affects the strength development of concrete. For example, Compare to ordinary Portland cement rapid hardening cement has higher strength gain in shorter. Low heat cement requires more time for setting compare to OPC. Temperature – High temperature of concrete and surrounding at the time of placing concrete makes it achieve higher strength in shorter times. During winter, the strength gaining process becomes slower. Size of the concrete member: Size of the concrete member also matters in strength gaining process. Large-sized concrete section members gain strength in a shorter time than smaller sections. How Long Should Concrete Cure Before Removing Forms
Time of Removing Formwork as per ASTM: Sr. No
Type of Cement
Time of De-shuttering