In vitro evaluation of the effect of SP200 lubricant on compressive strength of lightweight concrete with Leca aggregate and Powdered silica

Document Type: Original Article


1 Expert at the Building Materials Institute of the Apadana Institute of Higher Education, Shiraz, Iran.

2 Instructor of Civil Engineering Department, Islamic Azad University, Eghlid Branch, Shiraz, Iran.



In today's advanced world and due to advances in various scientific fields of concrete industry has also evolved and light concrete production is a result of these advances. It has had its advantages, many efforts have been made in the past to improve the quality and efficiency of concrete, and today the use of additives helps us to achieve this goal. The additive in this study is lubricant based on polycarboxylate brand SP200 and Powdered silica. The use of silica is also widely used in advanced countries due to its pozzolanic properties. In this study of 20 mixing designs, 2 of which were used as control sample and 18 with SP200 super-lubricant and microsilica powder, the results show that in the first mixing design with 0.49 water / cement ratio the highest compressive strength of The 7 and 28 days  is related to M / 35/5 sample which has 0.35% super-lubricant and 5% microsilica powder And in the second mixing scheme with water / cement ratio of 0.55, the highest compressive strength is related to the sample of  M /35/10 It contains 0.35% super-lubricant and 10% Powdered silica.  The use of silica and super-lubricant in the manufacture of lightweight concrete has increased the compressive strength of lightweight concrete in some of the samples.