An Jirapong Wachirathamrojn creator Pichai Nimityongskul Chairperson Thanakorn Pheeraphan Co-Chairperson Nii, Kazuyoshi Examination Committee Takewaka, Koji Examination Committee Royal Thai Government I Human Resource Development Program (Phase II) Scholarship Donor text series technical report th Bangkok Asian Institute of Technology 2001 continuing eng 108 leaves The accelerated strength of concrete cured with microwave energy is measured to estimate the 28-day compressive strength of normal concrete containing fly ash. The optimal microwave curing process involving heating duration, power, delay time, early age test time and later age test time, is determined first and then is employed to establish the 28-day strength estimation equation. Test parameters include the amount of fly ash replacement, namely 0%, 10%, 20% and 30% by weight of cement and mix proportions. The n01mal concrete mix proportions are designed according to the ACI mix design by using OPC Type I, Mae-Moh fly ash, river sand and limestone. The compressive strengths of 3"x6" specimens with various fly ash replacements and mix proportions are tested at the possible early age at 6.5 hours for microwave-cured specimens and at 28 days for normally cured specimens. A simple equation involving only 6.5-hour strength and percent of fly ash replacement can then be established for 28-day strength estimation. Based on the established equation, the estimation yields the average and maximum percentage of error at 5 and ±12. A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering, School of Civil Engineering Thesis (M.Eng.) - Asian Institute of Technology, 2001 Concrete Curing Strength of materials Concrete Additives Asian Institute of Technology. http://203.159.5.9/ait-thesis/detail.php?q=B09441 http://203.159.5.9/ait-thesis/detail.php?q=B09441 010713 20260817162920.0