Home » Highway Engineering (Page 2)
Category Archives: Highway Engineering
We did some studies a few years ago on the state of pavement engineering in the Philippines. Among the things we found was that conditions for the proper curing of concrete used for pavements of national roads are not usually met. This applied mainly for both Portland Cement Concrete Pavements (PCCP), which was the main subject of our study but also applied to Asphalt Concrete Pavements (ACP) as well as we documented practices for both types of pavements.
Last year, the traffic along Ortigas Avenue Extension was hellish for quite some time between the Rosario Bridge and Cainta Junction. One time, we eventually inched our way past De Castro, and lo and behold this scene while it was raining:
Rollers (pison) making a pass at the asphalt laid by a paving machine. Note the wet roads due to the heavy rains that afternoon.
Workers patching up the edges of the overlay as a foreman and what appears to be engineers directing them. That’s a asphalt paver in action. Note the already wet asphalt? That will have implications over the short term; often resulting in distress way ahead of the intended life of the ACP.
Dump trucks lined-up carrying aggregates for the asphalt overlay; occupying one lane of Ortigas Avenue Extension.
The queues from the westbound side stretched from Countryside to Junction. Since the intersection was already affected by the spillover, the section from Junction to Brookside was also congested.
The situation I described above is something that could have been managed other ways but would still result in severe traffic congestion as at least 2 lanes were occupied by construction (one being paved and another for staging). There were also other incomplete drainage works that exacerbated the situation. So as far as traffic management goes, I thought the contractor did the best it could given the conditions. However, I question the asphalt overlay work during heavy rains. The implications is the reduction in the intended or design life of the ACP (i.e., reduced life most likely due to the rainwater and wet conditions with the bitumen not being able to bind the aggregates as effectively as desired. And so that means the aggregates tend to loosen up more quickly resulting in the deterioration of the pavement and lead to more costly maintenance of roads.
A new bridge had been under construction beside the older Barkadahan Bridge. Instead of expanding the existing bridge, the proponents decided to build another bridge likely so as to reduce disturbance of traffic along the already congested first bridge. This is the same strategy for the bridge across the Pasig River in Nagpayong/Napindan that will reduce the potential bottleneck for when C-6’s expansion is completed. Unfortunately, the bridges don’t seem to include provisions for exclusive bicycle lanes that are clearly incorporated along much of C-6.
I took this photo as we were in queue at the approach to the intersection of Highway 2000 and the Manggagan Floodway’s East Bank Road. The new bridge can be seen here bearing eastbound traffic. The alignment at the intersection has not been addressed and so requires through traffic to basically swerve towards the entry to Highway 2000.
Here’s the intersection and the newly opened bridge. Note the vehicles coming towards my position as they follow a trajectory from the bridge to the narrow exit leg of Highway 2000.
Instead of a single lane along each direction, the two bridges now allow for at least 2 lanes of traffic either way. I say at least because a case can be made for 3 lanes to be indicated (there are no lane markings yet). The issue here though is that there is significant truck traffic crossing the bridge and two trucks traveling beside each other easily occupies the entire bridge. Thus, maybe a wide two lanes can be designated for both bridges with an opportunistic third lane forming depending on the traffic.
We conclude the month of October with the following recommended readings:
- Designing Walkable Urban Thoroughfares: A Context Sensitive Approach, An ITE Recommended Practice, 2010
- Model Design Manual for Living Streets, 2011
- Smart Transportation Guidebook, Planning and Designing Highways and Streets that Support Sustainable and Livable Communities, 2008
While these are guidelines and manuals developed and published in the United States, the principles and much of the content and context are very much applicable here.
As an additional reference, here is the latest version of functional classifications for streets that is supposed to be context-sensitive:
- Stamatiadis, N., A. Kirk, D. Hartman, J. Jasper, S. Wright, M. King, and R. Chellman. 2017. An Expanded Functional Classification System for Highways and Streets. Pre- publication draft of NCHRP Research Report 855. Transportation Research Board, Washington, D.C.
It seems late but there seems to be no really significant changes to the state of Circumferential Road 6 as the rains seem to have slowed down work on sections of the highway. We took these photos 3 weeks ago showing the nice 2-lane/2-way section on the side of the Laguna de Bay that’s been opened to general traffic. Previously, most vehicles had to use the beat-up, crater-plagued older section of what was a dike road. We were heading to SLEX via Bicutan so we were able to take a lot of photos for the entire stretch of C-6. I won’t be annotating all the photos anymore but suffice it to say that the series starts just after the Napindan Bridge in Pasig and ends prior to Taguig City’s bayside park at Lower Bicutan. Vehicles bound for C-5 or BGC via Ruhale Street should get off the newer section and negotiate a short but very bumpy road that’s not a good experience if you’re using a car. Just after the Ruhale “exit” all vehicles would have to return to the old road and have to be patient with the bad conditions of the pavement on both sides of the road.
The Transportation Science Society of the Philippines (TSSP) holds its 24th Annual Conference tomorrow, July 21, 2017. It will be held at the National Center for Transportation Studies at the University of the Philippines Diliman, Quezon City. More than a hundred participants are expected to attend this 1-day affair.
The final program for the conference may be found in the following link:
The theme for this year’s conference is “Improving Quality of Life in Urban and Rural Areas Through Inclusive Transportation.” This is also the theme for the panel discussion in the morning. The afternoon will feature four parallel technical sessions where 18 papers will be presented.
The keynote lecture will be delivered at the start of the conference by Prof. Tetsuo Yai of the Tokyo Institute of Technology, who is also the current President of the Eastern Asia Society for Transportation Studies (EASTS) under whose umbrella the TSSP is part of. TSSP is a founding member of EASTS and actually preceded EASTS by a year.
I have not used Circumferential Road 6 in a while. And so a couple of weeks ago, I was happy to see that work has resumed on the sections at Lupang Arenda in Taytay, Rizal, which is also known as Sampaguita Street. Here are some photos of the wide C-6 section. I guess there’s an opportunity here to have service roads on either side of the highway in order to manage/control local traffic. C-6, after all, is a highway and is designed for typical national highway speeds (i.e., 60 kph). The adjacent land use, however, requires slower traffic mainly due to safety concerns.
Cordoned-off section where a contractor is preparing the sub-base prior to placing the steel reinforcement and pouring concrete
Another photo of the section showing form works for the slab. Note the parked vehicles along the side on the left.
Some sections are already flooded from the heavy rains
The completed section towards Nagpayong, Pasig is a wide 4 lanes. At left is a nice view of the Laguna de Bai.
Section to Nagpayong near the boundary of Taytay, Rizal and Pasig City.
That’s a habal-habal (motorcycle taxi) terminal on the left and in front of a parked jeepney.
Two very important things about C-6 though. One concerns the Barkadahan Bridge over the Manggahan Floodway, which is too narrow for the traffic that cross it. There’s a new bridge beside it that seems to be taking too long to build. And then there’s the long stretch from Nagpayong, Pasig to Lower Bicutan, Taguig which remain in bad condition. The new section along the lakeside is already usable for Pasig-bound traffic but needs to be allowed to carry two-way traffic for the older section to be rehabilitated. C-6 is becoming a major alternative route for a lot of travelers from Rizal to and from Makati and Taguig (esp. BGC). It needs to be improved immediately as it can help decongest the Ortigas Ave. – C5 route that most Rizalenos use to go to their workplaces.
Last May, we went to a zoo in Rodriguez (formerly Montalban), Rizal. Using Waze for directions to the zoo, the app took us to a submersible bridge across the wide Marikina River from the main highway (M.H. Del Pilar) to the mainly residential area where the zoo was located. Following are photos of the submersible bridge and the newer more conventional bridge located a little further down the highway.
Submersible bridge connecting Barangay San Rafael with Barangay San Isidro
The “all-weather” bridge as seen from the submersible
There are many bridges like this submersible one across the country. Many were built as weirs or dams that could be used as bridges when the water level allowed it but could let water pass above it during wetter days. Incidentally, there’s one along a popular alternative route between Quezon City and Marikina in Tumana. That bridge can be impassable during times of heavy rains.