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I had not been to Baguio City for quite some time until June of 2016 (last year). And so I took a lot of photos of the roads between Metro Manila and Baguio including the three expressways (NLEX, SCTEX and TPLEX) and Marcos Highway. I have only posted photos of Marcos Highway ( a lot of them) and haven’t come to downloading photos of TPLEX that I have taken during my first time along the entire stretch at the time. To sort of make up for the backlog, I am posting the following photos of Kennon Road that I took almost 7 months ago. I assume most if not all roadworks along Kennon Road that some of the following photos show are already completed. I will no longer write captions for each of the photos but there are many landmarks shown here that can help the reader in his/her sense of direction and orientation. The following photos are of Kennon Road from Rosario, La Union to Baguio.
More photos from that June 2016 trip soon…
Still on Marcos Highway, the following photos complete this feature from my most recent trip to a city dubbed as the summer capital of the Philippines. This is the third part of the series on this major road to/from Baguio City, and sections pretty much show very similar characteristics as the previous ones in the preceding posts. Its been a while since the Part 2 of this series and since then, an additional section of the Tarlac-Pangasinan-La Union Expressway (TPLEX) has been opened further cutting down travel time between Manila and Baguio to 4 hours.
The approach to this curve reveals the uneven terrain on which the road was built.
These row houses and their driveways seem too close to the road
That’s a poorly placed driveway right in the middle of the curve
Many motorists tend to overtake slower moving vehicles via the opposing traffic lane. Here is a bus undertaking a passing maneuver at a curve!
Rockslide – these are frequent along mountain roads such as Marcos Highway. They are even more frequent along Kennon Road and Naguilian Highway.
Yet another section this time showing a reverse curve.
Here are a few more of the big bikes we encountered on our trip down from Baguio. These are of the same group of bikers in Parts 1 and 2.
Many sections of Marcos Highway have excellent sight distance and have usable, paved shoulders.
There is significant truck traffic along Marcos Highway. These, especially the loaded ones, often slow down traffic. In certain cases, trucks form platoons making it difficult to pass them.
I was not surprised to see a school along the highway since there are many communities along the road. This is a good example of standard signs and markings including a pedestrian crossing.
The curve is not a good location for a home.
The pavement at this section is intriguing as the road seems to have had a different orientation in the past. I suspect this was formerly a paved bay (for emergency stops or for loading/unloading passengers) in what used to be an unpaved shoulder.
The section shows also what looks like a bay along the inner (left in the photo) side of the highway. Note that the shoulder is rather narrow along the ridge-side (right).
Curve sections like this offer picturesque views but are actually are treacherous. The barriers are supposed to prevent vehicles from ‘flying’ out of the highway. Their designs should arrest large, heavy vehicles that may lose control and collide with the barriers.
Marcos Highway offers many breathtaking views and excellent sight distance along many portions.
This is the final stretch of Marcos Highway that terminates at the intersection with the Manila North Road, which is part of AH-26.
To open September, I continue on the feature on Marcos Highway. Following are more photos I took on our way back to Manila from a short vacation in Baguio.
Many sections of Marcos Highway have some form of protection against landslides or rock slides. Note the concrete faces fences along the left in the photo.
There are many structures along the highway including houses and stores
The mountain limits sight distance along curves like this.
We encountered this group of motorcyclists heading up to Baguio on what appeared to be what is termed as “big bikes”, that typically are the more expensive ones, too. Other photos in this series will show these motorcycles. I lost count of them while we were traveling the opposite direction.
This seems to be a popular stop for hungry travelers. The location though and its driveway are not at all desirable from the highway engineering perspective.
Combination of signs to guide motorists along this sharp curve.
Curved sections like this one offer breathtaking views of the mountains.
Shoulders may function as space for emergency stops including for breakdowns or changing tires. Full shoulders allow for stopped vehicles to be completely clear of the traveled way. That is, they don’t pose as obstacles that traffic would need to evade.
More examples of poorly located establishments along a curve
The road seems to disappear in the mountains
Conspicuous location for a religious site along the highway
More motorcyclists and their big bikes
Barriers along both side of the highway seem sturdy enough to keep vehicles from flying off the road in case their drivers/riders lose control. This section offers enough to satisfy sight distance requirements and noticeably does not feature double yellows like the other photos in this post.
A residential community along the highway including this big house just clear of the shoulder.
Another community including a home atop the mountain. The barriers appear to be newly constructed along with the PCC paved shoulders. These would have to be painted for them to be visible to motorists especially at night-time or when visibility is poor.
More photos of Marcos Highway soon!
The 23rd Annual Conference of the Transportation Science Society of the Philippines (TSSP) was held at the University of the Philippines (UP) Diliman last August 8, 2016. It was hosted by the National Center for Transportation Studies (NCTS), which for some time was practically inactive in its dealings with the society. The conference was a very successful one with more than 170 participants, mostly students from the undergraduate programs of Mapua Institute of Technology (MIT), De La Salle University (DLSU) and UP Diliman.
The Proceedings of the 23rd Annual Conference contains 22 technical papers, which I have already listed in a previous post showing the technical program for the conference. The link is to the current website of the TSSP hosted by NCTS. Those wishing to have copies of the papers may download them directly from the link. Meanwhile, those interested in the presentations should contact the authors. Their contact information are stated in the paper and it is ethical to get the nod of the authors for their presentation file as these still fall under what can be defined as their intellectual property. I am aware of people who tend to get presentation slides and then pass them of as their work when they use the slides or the data/information therein. There are proper ways for citations of references and sources but sadly such ways are not observed by many.
A highlight of our recent road trip to and from Lucena, Quezon via the Rizal – Laguna – Quezon route is the impressive roadside views of the new Pillila Wind Farm. The array consists of 27 turbines, more than the number in Bangui, Ilocos Norte. Following are a few photos of the turbines of the farm which has a total capacity of 5.2 Megawatts. I noticed though that many of the turbines were not running so the capacity is likely not reached and the output highly varies depending on the season and time of day.
There are two access points from the national highway to the wind farm. Via these access roads, one can get near the wind turbines to get photos including ‘selfies’ with the turbines as background, just like those trending photos posted on social media taken at the Bangui Wind Farm.
The Philippines needs more of these clean energy sources. The promotion and spread of such types of energy generation should be able to reduce our dependence on fossil fuels. This would be good in the long run and also for transportation since there are already many initiatives for electric vehicles. E-vehicles are not necessarily zero contributors to air quality and ultimately to climate change if we consider the sources of electricity when these vehicles re-charge their batteries.
A prominent architect was always posting on his social media account about how much of what’s wrong with our infrastructure (especially transport-related) are due to engineers. It was a sad commentary particularly because he wasn’t mentioning anything about the involvement and responsibility of architects in the planning and design of infrastructure. For most projects that fall under the category of ‘planned development’ including mixed use developments like the Eastwoods, BGCs, Nuvalis, MOAs, and other similar projects are planned and designed mainly by a team of architects. Highways and streets are part of these projects and often, engineers are given the task of detailing and in certain cases, analyzing and ending up with the responsibility to justify designs provided to them. So for those types of projects funded or led by the private sector, its probably the architects who have much say in the plans and designs and who should be scrutinized for their shortcomings in as far as sustainable or “green” criteria are involved.
It is a whole different story, however, for public roads, especially those that are classified as national roads. The reality is that many DPWH engineers need to re-tool, learn and practice principles of sustainable infrastructure design. This includes incorporating green or environment-friendly design principles, which includes consideration of the landscape. We met some DPWH engineers in one seminar before on sustainable transport who thought environmentally sustainable transport (EST) was simply environmental impact assessment (EIA) and who proudly claimed they already knew about the topic. I think many engineers and planners in government need to unlearn many things and dissociate their minds from a lot of what they have come to accept as standard, acceptable or correct that are actually sub-par, archaic or flawed. Kapag nakasanayan na at matagal nang ginagawa o ginagamit ay napagkakamalang tama at angkop kahit na sa katotohanan ay hindi.
A good appreciation of history and heritage also appear to be scarce these days whenever the DPWH is involved. Proof of this are the road widening projects in Leyte and Iloilo that now threaten many ancestral houses that are located along the national roads. Many contend that road widening is unnecessary because congestion has not set in along many of the sections that have been widened or are candidates for such projects. It can be seen along many widened roads along Tarlac and Pangasinan, for example, that the problem is not really congestion but poor enforcement of transport and traffic regulations. Such include tricycle operations, roadside parking, and encroachments on the road right of way (RROW).
In most cases its pure and simple analysis that needs to be conducted first. Are roads really congested and requiring additional lanes? The evidence does not seem to support many cases of road widening as data on congestion from the DPWH Atlas itself requires validation on the ground. A recent World Bank study, for example, found that for many national road sections reported as congested in the Atlas, the opposite is true when validated on the ground. Such issues with data that are used as basis for decisions whether sections need to be widened are serious and lead to a waste of funds as well as negative impacts on heritage or historical structures.
The DPWH still needs to do some re-inventing and should actually take the lead in many initiatives. Among these are those pertaining to what are being referred to as “complete streets.” Last week, there was an article in newspapers where the DENR called for pedestrian and bike lanes along roads. The call was not specific to national or local roads but it is something that the DPWH should have already anticipated and working at for roads under it jurisdiction given the outcomes of the International Road Assessment Program (iRAP) project that covered several thousand kilometers of national roads that pointed to the need to improve roads to improve safety for pedestrians and cyclists. It is a matter of having progressive or dynamic rather than reactive or static stance at the DPWH and this requires more than just the rudimentary engineering background for the agency to take road planning, design and construction to another level.
Following is a Position Paper prepared by the Institute of Civil Engineering and the National Center for Transportation Studies to clarify some issues pertaining to truck overloading. The position paper was presented to the Technical Working Group under the House of Representatives Committee on Transportation, which is handling the issue.
This position paper was crafted to clarify some issues pertaining to truck overloading and the implementation of the national law (R.A. 8794) from a technical standpoint, and based on an independent assessment of the concerns put forward recently.
Among the issues raised were on the maximum axle load of 13.5 tons, the computed maximum gross vehicle weight (GVW), and the implications of their enforcement on the transport of goods and the trucking industry.
In the absence of extensive data from measurements on actual roads and bridges in the Philippines, reference is frequently made to tests and studies by the American Association of State Highway and Transportation Officials (AASHTO), which are adopted by many other countries.
2. Maximum axle load
For benchmarking purposes, an 8.2-ton axle is referred to as the equivalent single axle load or ESAL. One (1) ESAL is equivalent to a damage potential of 1.0 based on road tests conducted by AASHTO. Damage potential increases very rapidly as the axle load increases. The maximum axle load of 13.5 tons is equivalent to 60 times the damaging potential of an ESAL or 8.2-ton axle load.
The designation of a 13.5-ton maximum already takes into consideration the practice of overloading. (Note that the original maximum single axle load was 8.0 or 8.2 tons.) The 13.5 tons is based on studies conducted by the DPWH back in the 1990s (Philippine Axle Load Study or PALS), which determined the maximum single axle load that may be allowed without compromising the integrity of structures such as bridges. The study measured the weights of trucks throughout the country to establish typical weights for different types of trucks.
For tandem axles, a different maximum load is prescribed due to established findings by AASHTO that two closely spaced axles have a much greater combined damaging potential than two single axles that are far apart. To keep the damaging potential in check, AASHTO has established that in the case of tandem axles, each axle in the tandem should have a maximum load that is 20% less than the maximum allowed for single axles. Thus, the maximum axle load for tandem axles in the Philippines is 10.8 tons, for a total of 21.6 tons for the tandem.
A similar process of reduction is applied to tridem axles and so on, where the damaging potential changes as a function of the proximity of the axles to each other.
3. Maximum gross vehicle weight
The maximum gross vehicle weight (GVW) computation is partly based on the maximum single axle load. Thus, it is clear that a higher maximum single axle load leads to higher maximum GVW.
The GVW is computed based on the optimum distribution of loads for different types of vehicles. This optimum distribution considers the maximum allowable axle loads as discussed above (AASHTO, 1987) as well as the loading characteristics of bridges, for example as as detailed in the AASHTO LRFD Bridge Design Specifications (2004).
Further, the optimum loads also take into account the stability of the vehicle as it travels along highways and bridges.
The experience in the U.S. where a compromise was reached between government and the private sector concerning maximum GVW is possible because the weights are based on a maximum single axle load of 9.1 tons and the optimum distribution of load for different types of trucks.
4. Consequences of overloaded vehicles
In the previous sections, the impacts of overloading on road infrastructure such as pavements and bridges were taken into consideration. Overloaded vehicles, particularly trucks, can have detrimental effects on highway safety and traffic operations, too.
Highway safety and traffic operations
Overloading would particularly have impacts on the following handling and stability aspects for trucks, affecting safety in highways:
- Rollover threshold
- Steering sensitivity
- Low-speed off-tracking
- High-speed off-tracking
Meanwhile, impacts on traffic operations include:
- Speed on upgrades
- Expressway/highway merging, weaving, and lane changing
- Downhill operations
- Intersection operations
- Traction ability
- Longitudinal barriers
The above factors have been analyzed and are the subject of a special report by the Transportation Research Board of the U.S. (TRB, 1990). It has been established, for example, that involvement in fatal road crashes increases as the GVW range increases. Also, it has been established that increased truck weights lead to greater reductions in speed and difficulties in merging, weaving and lane changing, and require greater sight distances for safe stopping.
Modification of trucks
The modification of trucks here pertains to the addition of at least one axle with the objective of increasing the GVW while also decreasing the loads of the axles, in order to comply with maximum axle limits.
Any modifications on trucks, especially the addition of axles, should comply with traffic safety standards including those pertaining to handling and stability. Thus, modified trucks should comply with the specifications of the manufacturer or with established standards, if any, for the modification in question.
Any modifications should also be subject to inspections. Problems will arise if there are no standards. In such cases, the manufacturer or experts in the industry should be consulted. The LTO should defer to the recommendations and disapprove any modifications that are not complying with standards or recommendations by qualified persons especially the manufacturer.
In the absence of comprehensive studies on such modifications, data on road crashes or breakdowns (e.g., flat tires, broken axles) need to be collected in order to establish their frequency, determine how serious these tend to be, and ascertain what the crashes or breakdowns are attributed to. This would require detailed information on crashes and breakdowns over a period of, say, 2 to 5 years for statistical significance.
5. Conclusions and Recommendations
The 13.5 tons designated as the maximum single axle load in the Philippines already incorporated the practice of overloading and thus becomes non-negotiable considering that the DPWH has already taken into consideration the maximum loads that can be withstood by highway structures especially bridges in the country. This maximum single axle load is notably higher than the allowance in the US and most other countries.
The following are recommended for further consideration:
- State the allowable maximum axle loads in terms of single axle, tandem axles, tridem axles and so on, in order not to create confusion on the interpretation of the allowable maximum loads.
- Establish standards, type approval system, and monitoring system for truck modifications, in order to ascertain compliance with safety and stability standards.
- Conduct studies on actual axle loads and GVWs on a more regular basis, say every 5 years, by the DPWH, in order to establish a database from which allowable maximum axle loads and GVWs may be updated in aid of legislation.
- Conduct impact assessments.
The U.S. Department of Transportation (2000) recommendations that may be relevant in the impact assessments include:
- Infrastructure costs – including implications on road pavements, bridges and geometrics
- Safety impacts – including crash/accident rates, public perception, vehicle stability and control, and vehicle comparisons
- Traffic operations – impacts on road capacity and speeds
- Energy and environment – impacts on fuel consumption and vehicle emissions
- Shipper costs – impacts on cost of transporting goods
Impact assessments are essential in order to establish directions for determining the benefits and costs attributed to various scenarios that are currently being discussed at the TWG level. Such benefits and costs will serve as inputs in aid of legislation to improve on the provisions of R.A. 8794 and its Implementing Rules and Regulations.
Design standards particularly for road pavements and bridges in the Philippines are mainly based on AASHTO standards and specifications. The AASHTO standards and specifications are based on AASHTO design vehicles along with their prescribed weight/load distributions. It follows, therefore, that anyone adopting the AASHTO design standards and specifications like the DPWH should also adopt the AASHTO design vehicle specifications. Otherwise, the application of standards and specifications for design will be flawed, resulting in sub-standard infrastructure.
As a general rule, if the Philippines is to adopt a different set of load distributions, maximum axle loads, and gross vehicle weights for its trucks, the country should likewise develop or revise its design standards and specifications to match local experience or setting. This would require comprehensive studies to be led by civil engineering experts in the Philippines and patterned after similar studies conducted elsewhere including the United States.
AASHTO (1987) Guide for Maximum Dimensions and Weights of Motor Vehicles and for the Operation of Non-Divisible Load Oversize and Overweight Vehicles, Washington, D.C.
AASHTO (2004) LRFD Bridge Design Specifications, 3rd Edition, Washington, D.C.
Department of Transportation, U.S. (2000) Comprehensive Truck Size and Weight Study, Federal Highway Administration, Washington, D.C.
Transportation Research Board (2007) Legal Truck Loads and AASHTO Legal Loads for Posting, NCHRP Report 575, National Cooperative Highway Research Program, Washington, D.C.
York, J. and Maze, T.H. (1996) Applicability of Performance-Based Standards for U.S. Truck Size and Weight Regulations, Semisequicentennial Transportation Conference Proceedings, May 1996, Iowa State University Institute for Transportation.