Use of recycled and secondary aggregates in concrete: deformation properties

The characteristics of recycled and secondary aggregates: coarse recycled concrete aggregate (RCA), fine glass cullet aggregate (GCA) and fine copper slag aggregate (CSA), and their effects on concrete deformation properties: elastic modulus, creep and shrinkage, have been studied. A novel Analytical Systemisation method was developed for the analysis and evaluation of the results sourced from 713 studies, undertaken by 960 authors from 537 institutions in 46 countries during 1972–2017, forming a data matrix having over 400,000 data points. Aggregate physical properties were found to be affected by the crushing process, more so for RCA than GCA and CSA. It was found that RCA reduces the resistance of concrete to deformation, whilst GCA and CSA result in no change or an improvement. The change in the deformation was shown to be affected by aggregate content, concrete strength and other factors. Most of the existing models were found not to consider the aggregate effect in estimating the deformation of concrete. Three new empirical models, essentially based on aggregate stiffness in the form of aggregate absorption, aggregate content and its ratio to cement content, have been developed for estimating the deformation of concrete made with aggregate suitable for use in structural concrete

Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

Correction to: Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

The original version of this article unfortunately contained a mistake

Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

Crystalline Admixtures for Autonomous Healing in Concrete: The Past, Present and Future

International Conference on Structures, Material and Construction27Springer Lecture Notes in Civil Engineerin

Use of copper slag and washed copper slag as sand in concrete:a state-of-the-art review

This paper provides the gist of the systematic review undertaken, involving evaluation, analysis, repackaging and modelling of all the literature that could be sourced on the subject. Copper slag (CS) and washed copper slag (WCS), as to be expected, have essentially similar basic physical (although WCS is usually finer than CS) and chemical characteristics and therefore they can be treated as one material. In-depth analysis of 2192 test data sourced from the literature showed that, given all the basic material characteristics, CS/WCS can be used as the sand component for making all strength grades of concrete and giving similar (or in some aspects better) performance to the corresponding concrete made with natural sand. The special attribute of CS/WCS for lowering the mix water demand has been used by the authors to develop two simple models for utilising the potential water savings and estimating the strength gains that can be realised when designing concrete with CS/WCS for given strength at a specific age. It is demonstrated that the water-saving potential of CS/WCS can be used to make other recycled and secondary materials more acceptable for use in concrete. </jats:p

POTENTIAL USE OF PLASTIC WASTE AS NATURAL SAND IN MORTAR AND CONCRETE

CEB-FIB International congress 202