International Journal of Sustainable Built Environment最新文献

The use of geosynthetic in soil and coastal engineering is increasing and improving due to improvements in its engineering properties and fabrication techniques. While some geosynthetic coastal structures have attained advanced stage in terms of applications and efficiency, others still lack well-structured design formulas and specifications on a sound scientific basis, hence continued experimental works for the better understanding of the hydraulic performance, stability and modes of failure of these structures. Coastal areas are dynamic with unique geomechanical feature such as soil instability, which in any case, may affect the overall performance of coastal defence structures constructed on soft soil or weak foundation. This paper reviews the developments and applications of geosynthetics in soil stabilization and protection of coastal areas with emphasis on shoreline protection. Relevant empirical research data are presented as well as the present and likely future challenges in the use of geosynthetics in soil stabilization and coastal defence structures.

In order to arrest the incidence of global warming brought about by the emission of greenhouse gases notably CO₂ into the atmosphere, the use of materials that can substitute the material responsible for greenhouse gases is being promoted world-wide. One of these is rice husk ash (RHA) which has been found suitable by researchers to partially replace Portland cement in the production of concrete. This paper presents a comprehensive and up-to-date review of the work of numerous researchers on structure and properties of concrete containing rice husk ash (RHA) as partial replacement of ordinary Portland cement. Some of the findings are: (i) controlled incineration is required to produce RHA with structure that can result in structural concrete, (ii) the use of RHA resulted in increased water demand, (iii) up to 10% cement replacement with RHA will result in strength development comparable to the control specimens, and (iv) the use of RHA in concrete result in impervious RHA-concrete microstructure to agent of degradation like, sulphate attacks, chloride ingress, etc., as well as good shrinkage properties, and thus produce durable concrete when used. However, some areas such as the bending and shear responses (and allied properties) of reinforced concrete slabs and beams with RHA are presently not yet covered by researchers; they are therefore recommended for future investigation.

An attempt has been made to study the subsurface groundwater discharge (SGD) in the coastal Cuddalore region of south east India. Measurement for Radon, water level, Electrical Conductivity (EC) and pH in surface water for a total of twenty hours by hourly interval has been attempted and further correlated with tidal values calculated by WX Tide 32 software. The SGD measurements were made by using a modified seepage meter. The study reveals a match with water level variation and tide with minor variation due to influx of surface water. Saline discharges, fresh groundwater discharges and surface water mixing processes were identified along the coast. Lower SGD (37.24–79.16 cm/day) was observed during fresh groundwater discharge.

Purpose

The purpose of the paper is to establish links between Indoor Environment Quality (IEQ) factors that affect occupant productivity and Global Sustainability Assessment System (GSAS) building rating system. The paper analyses the current state of GSAS using a desktop study, survey and brainstorming session organised in a workshop with GSAS Certified Green Professionals (CGP).

Methodology/design/approach

The study was conducted in three steps. First, a comprehensive literature review was conducted to identify IEQ factors that influence occupant productivity in offices. The second step was a desktop analysis of current GSAS building rating system to identify criteria and submittals that may help to increase occupant productivity. It was followed by a facilitated workshop of GSAS CGPs that included a survey and a brainstorming session to highlight the current state of GSAS rated building performances on occupant productivity. The workshop was attended by 41 CGPs in Doha, Qatar.

Findings

The paper highlighted that GSAS needs to be updated to increase occupant productivity in GSAS rated buildings. A periodic post-occupancy survey in GSAS buildings should be mandated to ensure better occupant productivity. The paper also presented various methods to make GSAS rated buildings more occupant-friendly.

Originality/value

This study is the first study to analyse green building guidelines in the context of occupant productivity, especially in Qatar.

This paper evaluates the economic, environmental, and social benefits of large-scale energy efficiency programs for new and existing buildings in Qatar. Using data obtained from detailed energy audits, several proven energy efficiency measures have been analyzed through optimized based analysis to assess their impact on the energy performance for both new and existing buildings in Qatar. Moreover, a bottom-up analysis approach is considered to quantify the multiple benefits for implementing large-scale building energy efficiency programs for the building stock in Qatar. In particular, a more stringent energy efficiency code for the new constructions and three energy retrofit levels for the existing buildings are considered in the analysis. A novel macro-economic analysis using the concept of energy productivity is used to assess the cost-benefit of large-scale energy efficiency programs in Qatar. It is determined that the implementation of a government funded large-scale energy retrofit program for the existing building stock is highly cost-effective in Qatar. In particular, it is found that a large-scale energy efficiency retrofit program of existing buildings can provide a reduction of 11,000 GWh in annual electricity consumption and 2500 MW in peak demand as well as over 5400 kilo-ton per year in carbon emissions. In addition, over 4000 jobs per year can be created when this large-scale energy retrofit program is implemented over 10-year period.