Selection of Materials and Techniques for Use in Sealing GeotechnicalInvestigation Holes

摘要

Site investigations typically involve drilling or pushing holes to installsampling or sensing devices or to collect samples from beneath a site. Environmental regulations, generally administered by the states, require that all potential pathways be permanently sealed to preserve the integrity of any existing natural geological barriers protecting groundwater. A wide variety of grouts are available, and this research effort was undertaken to select and adapt grouts that can provide highly impervious, permanent seals. Special attention was given to finding grouts that had low viscosities and long pot lives required to successfully use the grouts with the through the rod grouting systems now available in some penetrometer units. Laboratory and field tests were undertaken with grouts prepared from sucrose retarded portland cement, calcium sulfate based cement, and calcium hydroxide activated slag.