Bench-scale testing of grouts for geo-slice peels

Geo-slicing is a novel in situ sampling technique developed in Japan to identify evidence of paleoseismicity in soil deposits not conducive to trenching. To preserve and enhance the stratigraphic features of the geo-slice sample, a "peel"is created from the vertical slice of the soil profile by laying a reinforcing cloth and a grout or adhesive over the slice. After the adhesive dries, the cloth is removed from the slice. A thin layer of soil remains attached to the cloth, creating the peel. The peel can then be examined for paleoliquefaction features such as dikes and sills of sand that are generally devoid of bedding structures. Previous geo-slicing studies used a highly toxic Japanese grout. To conform to modern environmental regulations, it is necessary to identify a less-hazardous grout that still produces a satisfactory peel. A bench-scale study of multiple adhesives for creating geo-slice peels was performed. Adhesives are evaluated for their efficacy in creating a relief that enhances the bedding structures of the soil slice and for other properties such as flexibility and hazard level. Of the eleven adhesives evaluated herein, flex seal liquid was identified as most suitable for creating geo-slice peels.