Mechanical and Microstructural Investigation of Geopolymer Concrete Incorporating Recycled Waste Plastic Aggregate.

The effective use of waste materials is one of the key drivers in ensuring sustainability within the construction industry. This paper investigates the viability and efficacy of sustainably incorporating a polylactic acid-type plastic (WP) as a 10 mm natural coarse aggregate (NA) replacement in geopolymer concrete. Two types of concrete (ordinary Portland cement-OPC and geopolymer) were produced for completeness using a concrete formulation ratio of 1:2:3.

The use of portable XRF as a forensic geoscience non-destructive trace evidence tool for environmental and criminal investigations.

Hand-held, portable X-Ray fluorescence instruments (pXRF) provide a means of rapid, in-situ chemical characterisation that has considerable application as a rapid trace evidence characterisation tool in forensic geoscience. This study presents both a control test study which demonstrates optimisation of the data collection process, alongside a range of individual forensic case studies, including heavy metal contamination, conflict archaeology, forensic soil characterisation, and verification of human remains, which together validate the technique and provide some comparison between field-based and laboratory-based pXRF applications. Results highlight the time-efficiency and cost-effectiveness of in-situ, field-based pXRF analyses for material characterisation when compared with other trace evidence methods.

Petrological and geochemical characterisation of the sarsen stones at Stonehenge.

Little is known of the properties of the sarsen stones (or silcretes) that comprise the main architecture of Stonehenge. The only studies of rock struck from the monument date from the 19th century, while 20th century investigations have focussed on excavated debris without demonstrating a link to specific megaliths. Here, we present the first comprehensive analysis of sarsen samples taken directly from a Stonehenge megalith (Stone 58, in the centrally placed trilithon horseshoe).

Ancient DNA, lipid biomarkers and palaeoecological evidence reveals construction and life on early medieval lake settlements.

Direct evidence of ancient human occupation is typically established through archaeological excavation. Excavations are costly and destructive, and practically impossible in some lake and wetland environments. We present here an alternative approach, providing direct evidence from lake sediments using DNA metabarcoding, steroid lipid biomarkers (bile acids) and from traditional environmental analyses.

Identification and analysis of man-made geological product particles to aid forensic investigation of provenance in the built environment.

Small (sub-mm) fragments of construction materials derived from geological products are common components of soil and dust samples from urban and industrial environments. These particles increase the complexity of a soil through the admixture of man-made materials with natural minerals within the soil matrix. One application of such indicators is in nuclear security investigations, where there is a requirement to determine the origin and process history of a nuclear material discovered outside of regulatory control.