• This is a journal article. It was published in the journal, Transportation Fleming, Frost, and Lambert 2 ABSTRACT The use of a portable lightweight deflectometer (LWD) for construction quality control or material investigation for earthworks and road construction is increasing around the world. This paper reviews the LWD as a field evaluation tool, discusses the test variables and data quality and concludes both on its usefulness and also its limitations for a variety of earthwork and road assessment scenarios. The paper aims to provide a state of the art reference document for LWD users, consultants, material specifiers, contractors and clients. It reviews data from road foundations (subgrades, granular capping and sub-base) and fully constructed in-service (thinly surfaced) roads, to demonstrate the flexibility of the LWD but also show that its determination of 'stiffness modulus' may differ from that of the conventional Falling Weight Deflectometer (FWD) to a varying extent. A series of laboratory investigations are presented that demonstrate the sensitivity to uniformity of plate/surface contact, and also limitations in the interpretation of peak displacement from the device. In conclusion, a good understanding of the device workings and careful specification of the test variables are required to both analyse the data correctly and permit comparison between data sets. The device is concluded to be a useful and versatile field quality control and pavement investigation tool, if an understanding of the device issues is considered by data users. INTRODUCTIONThis paper reviews the use of portable falling weight deflectometers (PFWDS) and the behaviour of the Lightweight Deflectometer (LWD) in detail. In this paper the term PFWD means any portable device for measuring a stiffness of material insitu, and the term LWD refers to the specific type of PFWD commonly known in Europe as the Prima, manufactured by Carl Bro (previously manufactured by Keros). The LWD is increasingly used for investigations of road construction materials and quality control. A background to the LWD development, a review of field data with a focus on correlation with the Falling Weight Deflectometer (FWD), and then specific laboratory investigations are presented. This paper is intended for reference by LWD users, consultants, material specifiers, contractors and clients.

To introduce a performance specification, pavement foundations must be designed using analytical methods incorporating the laboratory measured parameters of resilient elastic modulus and resistance to permanent deformation of the subgrade and foundation materials. This paper presents results from a program of repeated load triaxial tests performed on a range of fine-grained subgrades prepared in a number of states to evaluate these parameters for various design conditions. The results highlight several difficulties in measuring small strains on 'undisturbed' soils over a large strain range and in predicting and modeling long-term behavior.However testing at higher strains has shown that the deviator stress at which the cumulative permanent deformation starts to increase significantly, termed the 'threshold stress', approximates to 50% of the deviator stress at failure. In addition, the resilient modulus of the soils is shown to approach a low asymptotic value at higher deviator stress. Comparison between elastic and plastic behavior shows that the deviator stress at 'threshold' coincides with the stiffness asymptote. Using these correlations a simplified mechanistic design method for pavement foundations is proposed.

Resilience of the UK transport infrastructure network can be expressed as the imbalance between the physical condition of the network and the transport demands the network experiences. Forecasting changes of resilience in the long term (e.g. the 2050s) requires a structured, multi-disciplinary approach. The Engineering and Physical Sciences Research Council funded Futurenet project developed a model architecture to formalise such an approach and this paper addresses one component: the assessment of the influence of physical processes on asset condition. This requires the development of new, integrated physical-based models that respond to detailed inputs of forecast weather events (e.g. UK Climate Projections 2009). The results are plotted onto the infrastructure network for visualisation. Subsequent combination with user demand will then enable determination of network resilience at a range of spatial scales. The project has highlighted the need for better datasets, more sophisticated physical-based models and further analyses of complex feedbacks and interactions between physical processes and also with user behaviour.

Strigolactones (SLs) are the most recently discovered phytohormones, and their roles in root architecture and metabolism are not fully understood. Here, we investigated four MORE AXILLARY GROWTH (MAX) SL mutants in Arabidopsis thaliana, max3‐9, max4‐1, max1‐1 and max2‐1, as well as the SL receptor mutant d14‐1 and karrikin receptor mutant kai2‐2. By characterising max2‐1 and max4‐1, we found that variation in SL biosynthesis modified multiple metabolic pathways in root tissue, including that of xyloglucan, triterpenoids, fatty acids and flavonoids. The transcription of key flavonoid biosynthetic genes, including TRANSPARENT TESTA4 (TT4) and TRANSPARENT TESTA5 (TT5) was downregulated in max2 roots and seedlings, indicating that the proposed MAX2 regulation of flavonoid biosynthesis has a widespread effect. We found an enrichment of BRI1‐EMS‐SUPPRESSOR 1 (BES1) targets amongst genes specifically altered in the max2 mutant, reflecting that the regulation of flavonoid biosynthesis likely occurs through the MAX2 degradation of BES1, a key brassinosteroid‐related transcription factor. Finally, flavonoid accumulation decreased in max2‐1 roots, supporting a role for MAX2 in regulating both SL and flavonoid biosynthesis.

A Workplace Parking Levy (WPL) scheme raises a levy on private non-domestic off street parking provided by employers. In April 2012 Nottingham became the first UK City to implement such a scheme with the revenue generated hypothecated for funding transport improvements. The lag between the introduction of the WPL and the opening of related public transport improvements represents an opportunity to study the impact of a WPL on congestion as a standalone measure. In order to achieve this it is necessary to consider changes to variables external to the WPL, which also impact on congestion, which may obscure any beneficial impact of the scheme. An autoregressive time series model which accounts for the impact of these exogenous variables is used to evaluate the impact of the introduction of the WPL on congestion. Delay per Vehicle Mile is used as the dependent variable to represent congestion while the number of Liable Workplace Parking Places (LWPP) is used as a continuous intervention variable representing the introduction of the WPL. The model also contains a number of economic, transportation and climatic control variables. The results indicate that the introduction of the WPL as measured by the number of LWPP has a statistically significant impact on traffic congestion in Nottingham. Additionally, external explanatory variables are also shown to impact on congestion, suggesting that these may be masking the true impact of the scheme. This research represents the first statistical analysis of the link between the introduction of a WPL and a reduction in congestion.