Dispersal of a termiticide foam beneath concrete slabs

Abstract

A 1% (AI) chlorpyrifos termiticide foam was applied beneath concrete slabs through holes spaced 30 and 45 cm apart, and 10, and 20 cm from a wall. Application was made to slabs with no void between the underside of the concrete and the top of the gravel fi11, and to slabs with a 4 cm void between the concrete and gravel. Foam was appiied at the rate of 15 liters/3 linear m with a straight-tip nozzle. After 24hr 5g samples of the top 2.5 cm of soil were taken from four locations: directly beneath the application hole, at the wall in front of the application hole, equal distance between two application holes, and at the wall, equal distance between two application holes. A continuous band of insecticide-treated soil resulted from the foam application using the three hole spacings. There was no significant difference in the amount of chlorpyrifos in the soil at the four samp]ing locations for the three hole spacings, and for slabs with and without a void beneath the slab. 'I"he water layer wa's discarded, and the hexane layer was added to the hexane layer from the previous separation, along with 20 ml of distilled water, This mixture was gently agitated for 30 sec and allowed to set for IO min. The water layer was discarded, the hexane layer

Rice Straw on Apparent Density of Foam Concrete

“…However, its composition is not so rigid and fixed. In many cases, it can be changed according to the target requirements and some other things can be added, such as chopped fibers and organic polymer [10]. Rice straw was added in this experiment.…”