640 research outputs found
The Effects of Biogeotextiles on the Stabilization of Roadside Slopes in Lithuania.
Soil erosion, Water erosion, Soil conservation, Geotextiles, Geotextile mats, Roadside slopes, Vegetation cover, Biogeotextiles , Palm mat geotextiles - Borassus aethiopum - Mauritia flexuosa - Buriti mats - BORASSUS Project - LithuaniaBiogeotextiles constructed from the leaves of Borassus aethiopum and Mauritia flexuosa are investigated at the Kaltinėnai Research Station of the Lithuanian Institute of Agriculture, which is participating in the EU-funded BORASSUS Project. Biogeotextiles are potentially excellent biodegradable and environmentally-friendly materials useful for soil conservation. Field studies on a steep (21–25°) roadside slope in Lithuania suggest biogeotextile mats are an effective and sustainable soil conservation technique. Biogeotextiles have a potential as a biotechnical soil conservation method for slope stabilization and protection from water erosion on steep industrial slopes and may be integrated with the use of perennial grasses to optimize protection from water erosion. The investigations demonstrated that a cover of Borassus and Buriti mats improved the germination and growth of sown perennial grasses. The biomass of perennial grasses increased by 52.0–63.4% under cover of Borassus mats and by 18.6–28.2% under cover of Buriti mats. Over 2 years, the biogeotextiles (Borassus and Buruti, respectively) decreased soil losses from bare fallow soil by 90.8% and 81.5% and from plots covered by perennial grasses by 87.9% and 79.0%, respectively
Evidence for improved urban flood resilience by sustainable drainage retrofit
The rapid growth of cities under modern development pressure has resulted in surface water flooding becoming an increasing hazard and future climate change uncertainties may exacerbate this threat still further: retrofitting sustainable drainage systems to attenuate stormwater runoff has been advocated as part of an integrated solution required to address this problem. Many of these adaptations not only enhance a community’s resilience to flooding, but may also offer additional benefits in terms of improved environmental amenity and quality of life. The evidence base for sustainable drainage is critically evaluated in respect of the implications for urban planning, as applied to existing housing stocks and business properties in urban areas worldwide. It is concluded that this approach can make a substantial contribution towards urban resilience as part of an integrated approach to managing extreme storms. This will be of interest to urban planners and designers considering the implementation of integrated flood risk management
Guest editorial: Building Performance and Sustainable Infrastructure: Unsustainable Return to Practice
The abrupt decline in global carbon emissions experienced during the pandemic was not sustainable. Overwhelmingly, this is evidenced by the advanced economies’ swift return to close to pre-pandemic levels and, of greater concern, the total global use of fossil fuels has rebounded to their highest level in history (IEA, 2021; Jackson et al., 2022). Unfortunately, post-pandemic, the anthropic life threating activities have resumed
Assessing the accessibility of the Wolverhampton interchange, UK
© 2015, Thomas Telford Services Ltd. All rights reserved. The UK Disability Discrimination Act (DDA) of 2005 requires transport service providers and local authorities to make reasonable infrastructure adjustments to accommodate the needs of disabled transport users. This paper presents the findings of a study that aimed to evaluate the extent to which the recently developed Wolverhampton Transport Interchange project meets the requirements set out in the Disability Discrimination Act. The study involved the implementation of a questionnaire survey of disabled users and semistructured interviews with stakeholders of the project. Site audits on three transport interchanges were undertaken for assessing the services offered and for enabling a comparative study. The paper presents the perceptions of users with various disability types regarding the infrastructure offered and concludes that the legislation had made an impact on improving the accessibility for disabled users, but what is needed is a process of rationalisation. Data from the transport interchange providers showed evidence of reasonable adjustments to meet the needs of the disabled, but obstacles to full compliance remained and further improvements could be made in order to enhance the services offered to the disabled users
Experimental evaluation of changes in strain under compressive fatigue loading of brick masonry
© 2017 Elsevier Ltd Assessing the long-term performance of masonry structures and their response to increased loading conditions are critical to safety and maintenance. A series of laboratory tests have been carried out on brick masonry to assess its performance under long-term fatigue loading. The relationship between stress levels and number of cycles to failure was identified under compressive loading, together with stress-strain evolution at various stress levels. Strain evolution shows distinctive characteristics for the three stages of deterioration and increased strain for increased number of cycles. Experimental results provide useful data for developing analytical prediction models for the fatigue deterioration of masonry structures
Critical BIM qualification criteria for construction pre-qualification and selection
© 2017 Informa UK Limited, trading as Taylor & Francis Group. Despite emerging research on Building Information Modelling (BIM) capability, there remain no studies that specifically look at criteria for the pre-qualification and selection of construction supply chain (CSC) firms for BIM projects. As a consequence, there is insufficient theoretical insight and empirical justification for critical BIM qualification criteria for the CSC context. In order to bridge this knowledge gap, a study was conducted to ascertain the most critical BIM capability attributes, as well as relevance to the pre-qualification and selection of suitable CSC firms for BIM-enabled projects. The relative importance of these criteria was determined based on their perceived influence on overall BIM delivery success on recent BIM-enabled projects. A sequential exploratory mixed methodological research design was adopted involving semi-structured interviews (n = 8) and a Delphi survey (n = 25) of experts, as well as a survey of CSC firms (n = 64) on BIM-enabled projects. The findings reinforce the criticality of past BIM experience in delivery success. Furthermore, it revealed that while technological infrastructure-related capacities (such as software and hardware availability) are perceived as very important qualification criteria, their actual contribution to delivery success is not as high in comparison to criteria related to previous BIM experience. This study provides insights on prioritising BIM capability criteria based on evidence on their contribution to delivery success in practice rather than their perceived importance as capability metrics
Performance of Sustainable Road Pavements Founded on Clay Subgrades Treated with Eco-Friendly Cementitious Materials
Clays encountered during road construction are mostly weak and result in major pavement failures due to their low California bearing ratio (CBR) and high swelling potential. In this study, sustainable and eco-friendly waste materials including brick dust waste (BDW), ground granulated blastfurnance slag (GGBS), recycled plastic (RP) and recycled glass (RG) at varying proportions of 11.75% and 23.5% were used as partial replacement for cement and lime in clay treatment. After determining the water content by conducting Atterberg limit and compaction test, A CBR and swell characteristics of treated and untreated clay were also conducted. A road pavement design was conducted using the Design Manual for Road and Bridges (DMRB) as a guide to determine the performance of treated clay with varying CBR values. A road pavement failure analysis was also conducted to understand the defect formation within pavement structures supported by eco-friendly treated clay. The embodied carbon of treated clay was calculated and a life cycle cost analysis (LCCA) of flexible pavement with treated clay and road with imported materials was conducted. The results show a liquid limit of 131.26 and plastic limit of 28.74 for high plasticity index (clay 1) and liquid limit of 274.07 and a plastic limit of 45.38 for extremely high plasticity index (clay 2). An increase in CBR values from 8% and 9% to 57% and 97% with a reduction in swell values from 4.11% and 5.03% to 0.38% and 0.56% were recorded. This resulted in a reduction in pavement thickness and stresses within the road pavement leading to reduced susceptibility of the pavement to fatigue, rutting and permanent deformation. Very low embodied carbon was recorded for eco-friendly treated clay and a high life cycle cost (LCC) with clay removed and replaced with imported materials compared with clay treated using eco-friendly waste materials. The study concluded that carbon and overall construction costs can be reduced using waste materials in road construction. Owners and operators can save money when clay is treated and used in road construction instead of removing clay and replacing it with imported materials
Architects Requirements of Decision Support Tools to deliver Low Impact Housing Design in the UK: Insights and Recommendations
The construction industry is facing increasing pressure to address environmental performance earlier in the design process. For United Kingdom (UK) buildings, design is perceived to be the key in delivering the low carbon agenda. Hence, a fundamental change to designers’ approach in designing for low impact buildings is needed. A mixed method approach comprising of questionnaires to sustainable architectural practices were combined with interviews of architects in practice and academia. This is necessary to identify the gaps in the current use of Building Performance Energy Simulation (BPES) tools as design- decision support for architects, towards recommending the requirements of new generation architects’ friendly tools for the early and detail stages of the design process to deliver the sustainable housing design in the UK. The results indicate a limited number of architects use BPES tools; that is, until the later stage of the design process. Moreover, there is need to focus on tool development for architects decision-making process, especially at the conceptual stage, where major decision are taken. Thus, the study focuses on recommending requirements of architects’ friendly tools, fit for their design-decision making at various stages of the design process. As architectural design decisions vary significantly in terms of accuracy, flexibility, and the level of detail, the study recommends that: at the early stages of the process, where relatively minimal information is available, flexibility and approximation in BPES tools is more approximate to support design decisions. Nevertheless, as the design develops, and more information becomes available, precision and higher levels of detail in BPES tools are required. Keywords: Building Performance Energy Simulation Tools, Decision Making, Low Impact Buildings, Royal Institute of British Architects, Sustainability
Integrated delivery of quality, safety and environment through road sector procurement: The case of public sector agencies in Ghana
Poor quality, safety and environmental (QSE) performance within Ghana's road sector has been cited as a major challenge in the procurement of infrastructure. This study evaluates the applicability and level of integrated consideration of QSE in the delivery of roads through procurement by public sector agencies in Ghana. Integrated delivery is explored on the basis of theoretical and empirical evidence of an existing synergistic relationship among QSE in the management and delivery of projects. A mixed methodological design was adopted to investigate two public road agencies through a questionnaire survey and interviews of technical staff with procurement responsibilities. This was done concurrently with soliciting professional perspectives on the subject. Procurement is widely regarded as paramount to the delivery of better QSE in the Ghana road sector. However, the level of synergistic consideration is low, which is attributable to an over-reliance on traditional procurement arrangements as a result of non-supportive local procurement regulatory frameworks. It is further established that a general lack of know-how and experience in the use of modern and integrated procurement arrangements prevent effective management and realisation of QSE beyond the current focus on time and cost through procurement processes within public road sector agencies
Strain evolution of brick masonry under cyclic compressive loading
Long-term fatigue tests in compression were performed on low-strength brick masonry prisms under laboratory conditions at different maximum stress levels. The maximum and minimum total longitudinal deformations with the loading cycles were recorded. The experimental results revealed that fatigue life is divided into three distinct stages. The recordings were further analysed to develop an analytical expression for the prediction of the development of strain during the fatigue life of masonry. A set of three mathematical equations were proposed to predict the three characteristic stages of fatigue. The developed expressions, related the normalised total longitudinal strain with the normalised maximum applied stress. The proposed model provides good agreement with the mean available data at any maximum stress level and could be used to to evaluate the remaining service life, plan maintenance works minimising life-cycle costs and prevent premature failures Continuity of the curves at the intersection points in terms of slope and numerical values ensures accuracy of the method and results to a differentiable function
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