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The enhanced carbon footprint of the construction sector has created the need for CO2 emission control and mitigation. CO2 emissions in the construction sector are influenced by a variety of factors, including raw material preparation, cement production, and, most notably, the construction process. Thus, using biobased constituents in cement could reduce CO2 emissions. However, biobased constituents can degrade and have a negative impact on cement performance. Recently, carbonised biomass known as biochar has been found to be an effective partial replacement for cement. Various studies have reported improved mechanical strength and thermal properties with the inclusion of biochar in concrete. To comprehend the properties of biochar-added cementitious materials, the properties of biochar and their effect on concrete need to be examined. This review provides a critical examination of the mechanical and thermal properties of biochar and biochar-added cementitious materials. The study also covers biochar’s life cycle assessment and economic benefits. Overall, the purpose of this review article is to provide a means for researchers in the relevant field to gain a deeper understanding of the innate properties of biochar imparted into biochar-added cementitious materials for property enhancement and reduction of CO2 emissions.

Many of those working on construction sites are exposed to demanding work loads; construction workers lift and carry heavy materials and work in awkward postures. Occupational injuries and accidents due to poor ergonomics are more common in the construction industry and many times lead to human tragedies, disrupt construction processes and adversely affect the cost, productivity, and the reputation of the construction industry. In Sweden, it is reported that concrete workers have the highest relative work-related musculoskeletal injury frequency. Therefore, the use of ergonomic production methods to prevent this can have a significant human, social and financial impact. Research introduced here presents a case study of comparative analyses of ergonomic situations for concrete workers performing concrete casting processes. Three different ergonomic risk assessment methods were used to assess the physical strain, hand-arm vibration and noise affects risks involved in concrete casting work tasks. The combination of technical and managerial factors results in a system where workers are as efficient and safe as possible during their work tasks, and thus, makes the construction work environment sustainable. The aim of our research is to find practical methods to evaluate and compare two different concrete casting methods from an ergonomic perspective. The focus is on the production of cast-in-place concrete bridge constructions where the traditional concrete casting method is compared with the SCC (Self-Compacting concrete) casting method. To be able to identify work-related musculoskeletal injury risks due to concrete casting work tasks, QEC (Quick Exposure Check for musculoskeletal risks), PLIBEL (Checklist for identification for Ergonomics Hazards) and ErgoSAM (Ergonomic production technology method) methods were used. Ergonomic risks analysis methods QEC, PLIBEL and ErgoSAM have all shown capabilities to evaluate construction work activities and thus determine whether a construction work activity constitutes a musculoskeletal risk to the worker or not before any ergonomic intervention is introduced. As a result the present ergonomic risks emanating from work methods used in the traditional concrete placing can be significantly reduced with the use of self-compacting concrete (SCC) that eliminates awkward work postures, noise and hand arm vibration, thereby reducing if not eliminating musculoskeletal injuries among concrete workers during their concrete casting work tasks.

Maltreatment perpetrated by fathers may entail distinct characteristics and threats, and therefore differing effects from maltreatment perpetrated by mothers alone. This study examines the extent to which father perpetration of maltreatment is associated with variability in subsequent adolescent health outcomes relative to mother-alone maltreatment. A sample of youth ( N = 377) with recently completed Child Protective Services investigations concerning reports of maltreatment attributed to fathers and/or mothers was drawn from the second National Survey of Child and Adolescent Well-being. Youth were 11-17 years old ( M = 13.8, SD = 2) at 18-month follow-up. Predictor variables (baseline) included caseworker-reported perpetrator (father vs mother alone), maltreatment type and severity, and co-occurring risk factors (prior reports of maltreatment, caregiver substance use, serious mental health problems, and recent arrest or detention, and intimate partner violence). Outcome measures were youth-reported sexual risk behavior (the number of past-year sexual partners), substance use severity (use of illicit drugs other than marijuana, number of substances used, and CRAFFT raw scores), and parent-to-adolescent physical aggression (minor, moderate, and severe) at 18-month follow-up. Structural equation modeling assessed the effects of father perpetration on outcomes. Father perpetration was prospectively associated with more parent-to-adolescent aggression ( β = 0.16, p = .034) and less sexual risk behavior ( β = −0.17, p = .017) than mother-alone perpetration. Findings suggest protective effects of father perpetration relative to mother-alone perpetration on sexual risk taking but greater risk on further victimization by parents. Future research is needed to replicate findings and examine potential youth gender differences.