Underground soil and thermal conductivity materials based heat reduction for energy-efficient building in tropical environment

Alam, Muhammad Raisul; Zain, Muhammad Fauzi Mohd.; Kaish, A. B. M. A.; Jamil, Maslina

doi:10.1177/1420326x13507591

Cited by 28 publications

(10 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Moreover, the habitat in which a species is most commonly encountered might not always experience temperature close to their thermal limit, such as for species living in the leaf-litter layer of closed-canopy forests. For instance, in our results, the lowest CT max value observed, independently of the ramping rate used is of 38.3 °C, which remains 0.5 °C superior to the highest air temperature on record within Hong Kong (Hong Kong observatory), and in the absence of direct solar radiations, soil temperatures are similar or inferior to air temperature (Alam et al , 2015). Thus, for some habitats or microhabitats, temperatures measured in the field cannot be translated directly to a maximum temperature threshold.…”

Section: Discussioncontrasting

confidence: 44%

Critical Thermal maximum measurements and its biological relevance: the case of ants

Leong

Tsang

Guénard

2020

Preprint

View full text Add to dashboard Cite

Upper thermal limit (UTL) is a key trait in evaluating ectotherm fitness. Critical Thermal maximum CTmax, often used to characterize the UTL of an organism in laboratory setting, needs to be accurate to characterize this significant and field-relevant threshold. The lack of standardization in CTmax assays has, however, introduce methodological problems in its measurement and incorrect estimation of species upper thermal limit; with potential major implications on the use of CTmax in forecasting community dynamics under climate change. In this study we ask if a satisfactory ramping rate can be identified to produce accurate measures of CTmax for multiple species.We first identified the most commonly used ramping rates (i.e. 0.2, 0.5 and 1.0 °Cmin−1) based on a literature review, and determined the ramping rate effects on CTmax value measurements in 27 ant species (7 arboreal, 16 ground, 4 subterranean species) from eight subfamilies using both dynamic and static assays. In addition, we used field observations on multiple species foraging activity in function of ground temperatures to identify the most biologically relevant CTmax value to ultimately develop a standardized methodological approach.Integrating dynamic and static assays provided a powerful approach to identify a suitable ramping rate for the measurements of CTmax values in ants. Our results also showed that among the values tested the ramping rate of 1 °Cmin−1 is optimal, with convergent evidences from CTmax values measured in laboratory and from foraging thermal maximum measured in the field. Finally, we illustrate how methodological bias in terms of physiological trait measurements can also affect the detection of phylogenetic signal (Pagel’s λ and Bloomberg’s K) in subsequent analyses.Overall, this study presents a methodological framework allowing the identification of suitable and standardized ramping rates for the measurement of ant CTmax, which may be used for other ectotherms. Particular attention should be given to CTmax values retrieved from less suitable ramping rate, and the potential biases that functional trait based research may induce on topics such as global warming, habitat conversion or their impacts on analytical interpretations on phylogenetic conservatism.

show abstract

Section: Discussioncontrasting

confidence: 44%

Critical Thermal maximum measurements and its biological relevance: the case of ants

Leong

Tsang

Guénard

2020

Preprint

View full text Add to dashboard Cite

show abstract

“…In tropical climates, ground soil temperatures may range from around 15 C to 25 C, and so can be much cooler than the ambient air temperature. 28 Floor slabs in contact with the ground might, therefore, be effective in cooling a building by acting as heat sinks and potentially provide radiant cooling. This hypothesis was tested was removing the floor insulation from the building model that was developed for the Passivhaus building.…”

Section: Simulation Resultsmentioning

confidence: 99%

Applying the Passivhaus standard to a terraced house in a hot and humid tropical climate – Evaluation of comfort and energy performance

Sigalingging

Chow

Sharples

2020

Building Services Engineering Research and Technology

View full text Add to dashboard Cite

In a hot and humid tropical climate, natural ventilation brings high levels of moisture into dwellings that, together with occupant activity, can result in very elevated internal relative humidity levels. Coupling these high relative humidities with high internal air temperatures creates occupant thermal discomfort, which is typically ameliorated in the tropics using energy-intensive air conditioning systems. This paper has investigated the potential benefits for thermal comfort and energy usage of applying the German Passivhaus standard to tropical dwellings. By creating a super insulated and air-tight envelope, the Passivhaus standard reduces fabric heat transfer, controls air infiltration and provides low-energy comfort. Applying this approach to a tropical terraced house might be effective but could, potentially, have an adverse impact on mechanical cooling demand. This study took an actual terraced property in Jakarta, Indonesia and thermally modelled its performance as insulation and airtightness levels were incrementally improved up to the Passivhaus standard. Field measurements in the dwelling of air temperature and relative humidity were used to validate the thermal model of the existing house. The validated model then tested the feasibility of meeting the Passivhaus energy standard for cooling in the modified tropical house. Simulation allowed the effects of air conditioning (AC) and dehumidifiers on thermal comfort and cooling loads to be investigated. The research develop the Passivhaus building model that had the floor insulation removed to let the ground floor act as a thermal sink and potentially provide radiant cooling. Analysis revealed that the building’s predicted air temperatures were affected in a beneficial way by having the Passivhaus without floor insulation. Practical application: Cooling in hot and humid tropical region is an energy-intensive approach. Design approaches that can bring comfort and save energy for the occupant are essential. The success of Passivhaus standard in mild climate might be transferable to bring comfort in tropical housing. Best practice can be developed by analysing the Passivhaus building performance in hot and humid tropical region.

show abstract

“…There is a diurnal (daily) cycle, as well as a superimposed seasonal cycle (Figure 9). In the diurnal cycle, the temperature variation in the soil tends to be shallower (20-50 cm, e.g., [32]) whereas in the seasonal cycle temperature variations can go up to 10m depth [33]. This is mainly because much of the heat conducted through a soil profile is utilized to change the local temperature of the soil and there is a decrease in energy flux with depth.…”

Section: Impact Of Climate Change and Practical Implicationsmentioning

confidence: 99%

The Role of Soil Stabilisation in Mitigating the Impact of Climate Change in Transport Infrastructure with Reference to Wetting Processes

2021

View full text Add to dashboard Cite

Cost efficient and robust transport systems are of critical importance to future economic prosperity as well as for the society’s social and environmental well-being. However, current performance shortcomings in the transport infrastructure formations induced by extreme climatic events cause excessive maintenance requirements with increased costs and disruptions to commuters and loss of productivity in the freight services. This is particularly important in locations where soils are sensitive to moisture changes caused by extreme climatic events. In this paper the role of soil stabilisation in halting volumetric deformation and associated reduction in shear strength derived from the wetting processes (e.g., rainfall periods) is examined for an expansive soil. Two stabilizers commonly used in road construction are examined, i.e., hydrated lime and Portland cement. An additional non-traditional stabiliser composed of a blend of ground granulated blast furnace slag and hydrated lime is also considered. A series of one-dimensional swelling and direct shear box tests were conducted adopting vertical stresses relevant for pavements and simulate wetting process that can take place after a period of rainfall. Results indicate that while all stabilizers contribute to a reduction of swelling and smaller losses in shear strength upon wetting, the blend of blast furnace slag and hydrated lime is the most favourable in terms of carbon footprint.

show abstract

Underground soil and thermal conductivity materials based heat reduction for energy-efficient building in tropical environment

Cited by 28 publications

References 9 publications

Critical Thermal maximum measurements and its biological relevance: the case of ants

Critical Thermal maximum measurements and its biological relevance: the case of ants

Applying the Passivhaus standard to a terraced house in a hot and humid tropical climate – Evaluation of comfort and energy performance

The Role of Soil Stabilisation in Mitigating the Impact of Climate Change in Transport Infrastructure with Reference to Wetting Processes

Contact Info

Product

Resources

About