Reader’s Response, Draft #3

The article “Porous Asphalt Is King of the Road,” on the website Pave Green (n.d.), stated that porous asphalt is advantageous to the environment, enhances safety and is cost-effective. Porous asphalt is manufactured such that gaps are present for water to pass through and to a filtration bed underneath. As a result, it prevents flooding, filters contaminants in the water and enhances water standard. The article also mentioned that water spatter from vehicles vanishes, hence improving visibility for motorists, and reducing traffic accidents. Maintenance during winter is low, in view that minimal salt is required to remove snow on roads since snow liquefies at a faster rate on porous asphalt. Consequently, the use of pollutive de-icing agents is eliminated. The article also stated that porous asphalt costs about the same as standard asphalt. However, the overall construction cost is lower due to the reduced need for building of pipes and ground excavation.

While the article addressed the boons offered by porous asphalt (PA) by mentioning the material’s extensive usage in the US and its contribution to road safety in winter, its susceptibility to climate change sullies its own reputation. There are several factors of climate change that can negatively affect PA’s behaviour, thus undermining the article’s claim to PA’s ‘King of the Road’ status.

One major factor of climate change that can affect PA is the increase in moisture due to heightened precipitation. Though the article noted the comparable functionality of PA pavements to storm drains, it overlooked a consequence of moisture on the material itself. Makkonen et al. (2007) forecasted that the most affected area where precipitation is likely to rise in Europe due to increased heavy rain spells, is in northern European regions in contact with the Atlantic Ocean, and mountainous and elevated areas. The impact of additional precipitation on PA will be dependent on the ability of the underlying mixture of the pavement. If this mixture is not well prepped and becomes impermeable, water underneath the surface will swell and cause scouring, which is the loss of soil, of the lower layer mixture (Solaimanian et al., 2003). Most importantly, stripping, which is the functional deterioration of a pavement mixture by the loss of adhesive bond between asphalt binder and aggregate surface due to moisture, will occur. This will threaten the strength and durability of the layer. In due time, PA pavements in these highly precipitated areas will incur damage as a result of climate change.

Another factor of climate change that can affect PA is the increase in temperature. The article hinted on PA’s attribute in withstanding sub-zero temperatures, albeit without mentioning the effects of temperature increases. Thodesen and Hoff (2010) said that temperature rise may cause PA pavements to deform permanently if the pavement temperatures exceed the design temperatures. This may lead to uneven road compaction and the release of trapped water from within the air void structure. They also concluded that continued temperature fluctuations can also lead to cyclic loading of the saturated pavement, hence leading to the development of heightened pore pressures and stripping in the layers underlying the porous section of the pavement when using porous pavements.

In conclusion, what the article did not mention regarding the careful attention given toward the behaviours of PA in light of climate change should not be overlooked. Ultimately, as with all other pavement types, the success of PA is dependent upon proper design and construction. When properly designed and built, the PA surface can be a viable option when working in tandem with an integrated pavement system to serve a more deserving recognition for the title of ‘King of the Road’.

(606 words)

References

Makkonen, L., Ruokolainen, L., Räisänen, J., & Tikanmäki, M. (2007). Regional climate model estimates for changes in Nordic extreme events. Geophysica, 43(1-2), 19-42. Retrieved February 19, 2018, from https://www.researchgate.net/profile/Lasse_Makkonen/publication/254947036_Regional_Climate_Model_Estimates_for_Changes_in_Nordic_Extreme_Events/links/02e7e534eb3c8e7ff7000000.pdf

Pave Green. (n.d.). Porous Asphalt Is King of the Road. Retrieved February 4, 2018, from http://www.pavegreen.org/index.php?option=com_content&view=article&id=58%3Aking-of-the-road&catid=35%3Aporous-asphalt&Itemid=110

Solaimanian, M., Harvey, J., Tahmoressi, M., & Tandon, V. (2003). Test Methods to Predict Moisture Sensitivity of Hot-Mix Asphalt Pavements. In Moisture Sensitivity of Asphalt Pavements – A National Seminar (pp. 77-110). San Diego, California, USA: Transportation Research Board. Retrieved February 19, 2018, from http://onlinepubs.trb.org/onlinepubs/conf/reports/moisture_seminar.pdf

Thodesen, C., & Hoff, I. (2010, June). Study of Water Effects on Asphalt and Porous Asphalt (Research Report No. 5). Retrieved February 4, 2018, from http://www.cedr.eu/download/other_public_files/research_programme/eranet_road/call_2008_climate_change/p2r2c2/08_Deliverable-N5.pdf

Interpersonal Conflict

Air dicincang tidak akan putus. It is a Malay proverb which has a similar meaning to the English proverb ‘Blood is thicker than water,’ which is used to emphasise one’s belief that family connections are always more important than other types of relationship. I too, value familial relations and I usually make it a point to perform familial duties first before others.

A typical week’s routine for me is set according to my activities and duties. Weekends, for instance, are spent for voluntary community activities, and Thursday and Friday nights are mandatory periods with the family. Thankfully, my parents respect my routine and the time allocated for them, and they also help me ensure that I do not lapse in my responsibilities to others. But sometimes, prioritising can be a tricky act.

A few weeks ago, an urgent need for assistance from a friend for a communal activity on both family nights placed me in a tight situation. Usually, if I had to skip on any family night, I would inform my parents earlier that I would not be home. They would normally be understanding about it. However, this time was different. I had to skip two consecutive family nights. Despite informing the day before of my absences, my parents became upset when I reminded them on Thursday in our ride home. They angrily said that I had not prioritised our family night by spending time with others on almost every night and day. I was taken aback by their response. I replied saying that I had pre-informed them regarding this one-off schedule change. They then insisted that I tell my friend to reschedule that activity to other nights. In reply, I said that it was unreasonable of them to make that request from someone who urgently needed my assistance and that it was impossible to reschedule the activity. Amidst this tension, we remained silent throughout the rest of the ride.

If you were in my position, how would you handle this situation?

Reader’s Response, Draft #2

The article “Porous Asphalt Is King of the Road,” on the website Pave Green (n.d.), stated that porous asphalt is advantageous to the environment, enhances safety and is cost-effective. Porous asphalt is manufactured such that gaps are present for water to pass through to a filtration bed underneath. As a result, it prevents flooding, filters contaminants in the water and enhances water standard. The article also mentioned that water spatter from vehicles vanishes, hence improving visibility for motorists, and reducing traffic accidents. Maintenance during winter is low, in view that minimal salt is required to remove snow on roads since snow liquefies at a faster rate on porous asphalt. Consequently, the use of pollutive de-icing agents is eliminated. The article also stated that porous asphalt costs about the same as standard asphalt, however, the overall construction cost is lesser due to the reduced need for building of pipes and ground excavation.

While the article addressed the boons offered by porous asphalt (PA) through its extensive usage in the US and contribution to road safety in winter, the absence of reference to the material’s long term design considerations as a result of climate change, makes the article less than satisfactory in upholding PA’s status as ‘King of the Road’.

A major factor of climate change that can affect PA is the increase in moisture due to heightened precipitation. Though the article noted the comparable functionality of PA pavements to storm drains, it overlooked a consequence of moisture on the material itself. Makkonen et al. (2010) forecasted that the most affected area where precipitation is likely to rise, due to increased heavy rain spells, is in northern European regions in contact with the Atlantic Ocean, and mountainous and elevated areas. The impact of additional precipitation on PA will be dependent on the ability of the underlying mixture of the pavement. If this mixture is not well prepped and becomes impermeable, water underneath the surface will swell and cause scouring – loss of soil – of the lower layer mixture (D’Angelo & Anderson, 2003; Solaimanian et al., 2003). Most importantly, stripping – functional deterioration of a pavement mixture by the loss of adhesive bond between asphalt binder and aggregate surface due to moisture – will occur, thus threatening the strength and durability of the layer. In due time, PA pavements in these highly precipitated areas will incur damage as a result of climate change.

Like any other conventional asphalt mixtures, PA can also be affected by temperature increase because of climate change. The article hinted on PA’s attribute in withstanding sub-zero temperatures, albeit without mentioning the effects of temperature increases. Thodesen and Hoff (2010) said that temperature rise may cause PA pavements to deform permanently if the pavement temperatures exceed the design temperatures. This may lead to uneven road compaction and the release of trapped water from within the air void structure. They also concluded that continued temperature fluctuations can also lead to cyclic loading of the saturated pavement, hence leading to the development of heightened pore pressures and stripping in the layers underlying the porous section of the pavement when using porous pavements.

In conclusion, what the article did not mention regarding the careful attention given toward the behaviours of PA in light of climate change should not be overlooked. Ultimately, as with all other pavement types, the success of PA is dependent upon proper design and construction. When properly designed and built, the PA surface can be a viable option when working in tandem with an integrated pavement system to serve a more deserving recognition for the title of ‘King of the Road’.

(598 words)

Reference
Thodesen, C., & Hoff, I. (2010, June). Study of Water Effects on Asphalt and Porous Asphalt(Rep. No. 5). Retrieved February 4, 2018, from RoadERA.net website: http://www.cedr.eu/download/other_public_files/research_programme/eranet_road/call_2008_climate_change/p2r2c2/08_Deliverable-N5.pdf

Reader’s Response, Draft #1

The article “Porous Asphalt..,” on the website Pave Green (n.d.), stated that porous asphalt is advantageous to the environment, enhances safety and is cost-effective. Porous asphalt is manufactured such that gaps are present for water to pass through and to a filtration bed underneath. As a result, it prevents flooding, filters contaminants in the water and enhances water standard. The article also mentioned that water spatter from vehicles vanishes, hence improving visibility for motorists, and reducing traffic accidents. Maintenance during winter is low, in view that minimal salt is required to remove snow on roads since snow liquefies at a faster rate on porous asphalt. Consequently, the use of pollutive de-icing agents is eliminated. The article also stated that porous asphalt costs about the same as standard asphalt, however, the overall construction cost is lesser due to the reduced need for building of pipes and ground excavation.

While the article “Porous Asphalt…,” on the website Pave Green (n.d.), addresses the boons offered by porous asphalt (PA) in stormwater management and traffic safety, the lack of information regarding its design constraints and material performance due to climate change, makes the article less than satisfactory in promoting the material’s status as ‘King of the Road’.

A key factor of climate change that affects PA is the increase in moisture due to heightened precipitation. Makkonen et al. (2010) projected that the most significantly affected area where precipitation is expected to increase in Europe, due to increased heavy rain spells, is in northern European regions in contact with the Atlantic Ocean, as well as mountainous and elevated areas. The impact of additional precipitation on PA will be dependent on the ability of the underlying mixtures of the pavement. In the event the underlying pavement is not well compacted and becomes impermeable, water will accumulate under the surface and lead to scouring (loss of soil) of the lower layer mixture (D’Angelo & Anderson, 2003; Solaimanian et al., 2003). Most importantly, moisture causes functional deterioration of a pavement mixture by loss of the adhesive bond between the asphalt cement and the aggregate surface, hence threatening the strength and durability of the layer.

PA, like any other conventional asphalt mixtures, can also be affected by temperature increase due to climate change. In the event of increased temperatures, it is possible that porous pavements will experience permanent deformation if the pavement temperatures exceed the design temperatures. This may lead to uneven road compaction and release of trapped water within the air void structure. Thodesen and Hoff, 2010 concluded that continued temperature variation could also lead to cyclic loading of the saturated pavement, thus leading to the development of increased pore pressures and ultimately increased possibility of moisture damage. In some cases porous pavements retain moisture longer than conventional pavements. Additionally, studies have shown that when using porous pavements stripping occurs in the layers underlying the porous section of the pavement. Therefore, according to Roberts et al., 1996, in the event that a porous pavement solution is used it is of utmost importance for the underlying pavement section to be tested for moisture susceptibility (as cited in Thodesen and Hoff, 2010).

Ultimately, as with all other pavement types, the success of PA is dependent upon proper design and construction. When properly designed and built, the PA surface should be a viable option when working in tandem with an integrated pavement system to serve a more deserving recognition for the title of ‘King of the Road’.

(578 words)

 

Bibliography
Thodesen, C., & Hoff, I. (2010, June). Study of Water Effects on Asphalt and Porous Asphalt(Rep. No. 5). Retrieved February 4, 2018, from RoadERA.net website: http://www.cedr.eu/download/other_public_files/research_programme/eranet_road/call_2008_climate_change/p2r2c2/08_Deliverable-N5.pdf

Article Summary #final

The article “Porous Asphalt Is…,” on the website Pave Green (n.d.), stated that porous asphalt is advantageous to the environment, enhances safety and is cost-effective. Porous asphalt is manufactured such that gaps are present for water to pass through and to a filtration bed underneath. As a result, it prevents flooding, filters contaminants in the water and enhances water standard. The article also mentioned that water spatter from vehicles vanishes, hence improving visibility for motorists, and reducing traffic accidents. Maintenance during winter is low, in view that minimal salt is required to remove snow on roads since snow liquefies at a faster rate on porous asphalt. Consequently, the use of pollutive de-icing agents is eliminated. The article also stated that porous asphalt costs about the same as standard asphalt. However, the overall construction cost is lesser due to the reduced need for building of pipes and ground excavation.

(149 words)

[Revised 19/02/18]