Ibaraki, Japan's Bridges: Route 293 Bridge across the Satogawa (2)

June 2011 (36.536 Degrees, 140.540 Degrees) Satogawa Bridge

A view showing the temporary Bailey Bridge put up after the earthquake, the undamaged pedestrian bridge, and the old Satogawa Bridge with the girders moved off their bearings. Ibaraki Prefecture must be like a big green sponge. It is so soggy and wet that it is the only location during the 2011 earthquake where bridges got damaged due to liquefaction.

Ibaraki, Japan's Bridges: Route 293 Bridge across the Satogawa (2) by Mark Yashisnky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Ibaraki, Japan's Bridges: Route 293 Bridge across the Satogawa (1)

June 2011 (36.536 Degrees, 140.540 Degrees) Satogawa Bridge

The Satogawa Highway Bridge is a 189.2 m seven span reinforced concrete T girder bridge (with drop-in spans) that carries Route 293 over the Satogawa River. There is an undamaged pedestrian bridge just to the north and also a temporary Bailey Bridge to the north of that because the highway bridge was closed after the earthquake. The piers moved towards the river due to lateral spreading that damaged the bearings. 

Ibaraki, Japan's Bridges: Route 293 Bridge across the Satogawa (1) by Mark Yashisnky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Ibaraki, Japan's Bridges: The Joban Expressway across the Nakagawa

June 2011 (36.422 Degrees, 140.432 Degrees) Nakagawa Bridge

There are three bridges that cross at this bend of the Nakagawa. We already looked at the utility bridge and at Kunita Bridge but the biggest structure is the Nakagawa Bridge carrying the Joban Expressway. It is made up of a three span and a four span frame and has stocky pier walls with hammerhead caps supporting a steel box girder superstructure. Unlike the Kunita Bridge, this bridge was considered an evacuation route, it was retrofitted before the 2011 earthquake, suffered no damage, and continued to carry traffic.

Ibaraki, Japan's Bridges: The Joban Expressway across the Nakagawa by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Ibaraki, Japan's Bridges: Kunita Bridge across the Nakagawa (2)

June 2011 (36.418 Degrees, 140.434 Degrees) Kunita Bridge

A repaired column on the Kunita Bridge. This damaged column was epoxy grouted and then wrapped in a fiber composite. It looks like the soil around the column liquefied during the earthquake. 

I often go to Google Earth to find information about the bridges that I put in my blog. When I was looking for information about bridges in Tokyo, Google Earth was crowded with information but there was no information for any of the bridges crossing the Nakagawa in Ibaraki. 

Ibaraki, Japan's Bridges: Kunita Bridge across the Nakagawa (2) by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Ibaraki, Japan's Bridges: Kunita Bridge across the Nakagawa (1)

June 2011 (36.418 Degrees, 140.434 Degrees) Kunita Bridge

The Kunita Bridge is a six span double steel box girder bridge built in 1976 that carries Route 63 (between the utility bridge and the Joban Expressway) across the Naka River. The bridge sits on short and tall pier walls and the short pier walls were damaged during the earthquake. The damage was repaired by injecting epoxy grout into the smaller cracks and removing crumbled concrete and placing casings over the larger column damage. The bridge had moved tranversely during the earthquake and the expansion joint on the west side was replaced with a steel plate. Most of the steel bearings were damaged and so the girders were still sitting on steel blocks when we visited the bridge site.

Ibaraki, Japan's Bridges: Kunita Bridge across the Nakagawa (1) by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Ibaraki, Japan's Bridges: Utility Bridge across the Nakagawa

June 2011 (36.416 Degrees, 140.434 Degrees) Nakagawa Utility Bridge

Continuing northeast we arrived at the Naga River and a pretty utility bridge. I like the tower legs that seem ideally suited to carry the triangular cross-section of the superstructure. Imagine building a separate cable-stayed bridge to carry a waterline when there are two nearby highway bridges that could carry it for free. 


I'm fond of playing SimCity on my computer where I always have to be careful not to spend all my money on infrastructure. My impression is that Japan is willing to spend a lot more money on infrastructure than we do in the United States. 

Ibaraki, Japan's Bridges: Utility Bridge across the Nakagawa by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Ibaraki, Japan's Bridges: Rokko Bridge across Kitaura Lake (4)

June 2011 (36.086 Degrees, 140.540 Degrees) Rokko Bridge

A last look at the partially collapsed Rokko Bridge (on our left) and the new bridge being constructed on our right. Geotechnical engineers often measure the width of cracks on the river bank to determine how much lateral spreading occurred during an earthquake. However, if there was lateral spreading at this site, it must have occurred in the middle of the lake.

Perhaps there was just a loss of bearing capacity during the earthquake that allowed the pile bents to sink below the water's surface. My feeling is that this is an old, locally owned bridge that wasn't designed or retrofit to the standards of Japan's highway bridges.

Ibaraki, Japan's Bridges: Rokko Bridge across Kitaura Lake (4) by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Ibaraki, Japan's Bridges: Rokko Bridge across Kitaura Lake (3)

June 2011 (36.086 Degrees, 140.540 Degrees) Rokko Bridge

The Rokko Bridge is so skinny that I would imagine most people used a wider bridge to cross the lake (there are several locations where the bridge is wider to accomodate passing vehicles).

The approach settled about a meter but the pile bents held the bridge up (except where they disappeared in the middle of the lake). You can see the new bridge they were building at the time of the earthquake on the right. If you go to Google Earth, you can see that the new bridge now looks complete while the old bridge still is sitting with three spans missing. Maybe the authorities are considering what to do (if anything) about the old bridge.

Prof Fujino had us pose in front of the dropped spans for a group photo with his colleagues. It may seem a little strange posing in front of a collapsed bridge, but it took considerable effort for us (especially me) to get to this spot. There were only two bridges that collapsed due to ground shaking during the 2011 Tohoku Earthquake and the other bridge was in Fukushima Prefecture (where we weren't allowed to go).

Ibaraki, Japan's Bridges: Rokko Bridge across Kitaura Lake (3) by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Ibaraki, Japan's Bridges: Rokko Bridge across Kitaura Lake (2)

June 2011 (36.086 Degrees, 140.540 Degrees) Rokko Bridge

The Rokko Bridge lost two piers and three spans during the Tohoku Earthquake. Apparently the pipe piles weren't driven deep enough through the liquefiable soil. The bridge crosses a very long lake and so we had an hour’s drive to look at both approaches. There is a new bridge being built across the lake, but for now there is a long detour for people using Route 354.


A driver was going across the bridge and drowned when he drove off the bridge. He must have come from the north because the south approach had over a meter of settlement. The photo below shows details of the damage to the end diaphragm and bearings as the spans in the center of the lake were dragged away during the earthquake.

Ibaraki, Japan's Bridges: Rokko Bridge across Kitaura Lake (2) by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Ibaraki, Japan's Bridges: Rokko Bridge across Kitaura Lake (1)

June 2011 (36.086 Degrees, 140.540 Degrees) Rokko Bridge

The Rokko Bridge is a 405 m long steel girder bridge on piers composed of four battered steel piles.  The approaches settled (see photo below) and the bridge lost two piers and three spans during the Tohoku earthquake. This was similar to the damage that occurred to the Showa Bridge during the 1964 Niigata earthquake and probably had the same cause: loss of strength and stiffness of the soil due to liquefaction.

Ibaraki, Japan's Bridges: Rokko Bridge across Kitaura Lake (1) by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Ibaraki, Japan's Bridges: Kitaura Bridge across Kitaura Lake

June 2011 (36.033 Degrees, 140.565 Degrees) Kitaura Bridge

Continuing northeast we arrived at the Kitaura Bridge. It is a 1296 m long viaduct with five tied arch spans that crosses Kitaura Lake. The bridge carries Prefectural Route 186 on two lanes and a wide sidewalk. For some reason the bridge was planned in 1971, construction began in 1976, but the bridge wasn't opened until 1995. It suffered damage to the steel pot bearings during the 2011 Tohoku earthquake. The arch spans moved enough to pull the anchor bolts that restrained the bearings out of the concrete. 

Ibaraki, Japan's Bridges: Kitaura Bridge across Kitaura Lake by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 United States License.

Ibaraki, Japan's Bridges: Suigo Ohashi (利根川 水郷大橋) across the Tonegawa

June 2011 (35.909 Degrees, 140.491 Degrees) Suigo Bridge

Continuing east we arrived at the Suigo Bridge, a 535 m long cable-stayed structure over the Tonegawa. Three parallel cables suspended from a tower support two traffic lanes and sidewalks on each side of the tower. The bridge was completed in 1977 and won the Tanaka Prize like many other Japanese bridges we've studied in this blog.


It look likes the river banks were damaged by the earthquake and are covered to prevent erosion. Work is also occurring on the bridge, perhaps a new riding surface. The bridge is just west of the Yokotone Lock Gates at the confluence of the Yokotonegawa and the Tonegawa. This is at the boundary between Ibaraka and Chiba Prefectures.

Ibaraki, Japan's Bridges: Suigo Ohashi (利根川 水郷大橋) across the Tonegawa by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Ibaraki, Japan's Bridges: Kouzaki Bridges across the Tonegawa (2)

June 2011 (35.9105 Degrees 140.396 Degrees) Kouzaki Bridges

A few months after the Great Tohoku Earthquake, Professor Fujino at the University of Tokyo took me to see some of the bridges in Ibaraki Prefecture. I thought the rivers running through Tokyo were green oases until we drove into Ibaraki.

The Tonegawa was an ancient river that constantly flooded Tokyo until it was finally diverted east through Chiba Prefecture into the Pacific. After the recent earthquake (and the Fukushima nuclear power plant disaster) carp caught in the river were found to have increased amounts of radioactive cesium.

The Kouzaki Roadway Bridge is a long steel girder bridge that includes three tied arch spans on single column bents with hammerhead caps over the Tonegawa River. The arch spans are 48.8m, 49.2m, 48.8m and the approach spans are 79.2m. There is a parallel steel girder pedestrian bridge. Both bridges were built in 1967.

The roadway bridge was retrofitted quite recently with concrete casings around the columns and dampers, restrainers, and shear keys around the bent caps. During the earthquake, the site experienced liquefaction that damaged the piles, caused considerable movement of the spans, and cracks and spalls to the restrainer connections. The bridge was closed in May (two months after the earthquake) so it could be repaired. It is thought that the retrofit prevented unseating during the earthquake.

Ibaraki, Japan's Bridges: Kouzaki Bridges across the Tonegawa (2) by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License.

Tokyo Japan's Bridges: Metropolitan Expressway #7 Bridge across the Kyu Nakagawa

March 2012 (35.695 Degrees, 139.848 Degrees) Metropolitan Expressway Bridge

My last photo from a canoe on the Nakagawa Canal is of the same view from my June 4th blog, only without me in the photo. The Metropolitan Expressway is a long viaduct that carries the Komatsugawa Route in a east-west direction through southern Tokyo. An enormous city must have almost unlimited resources to squeeze in as many bridges as possible above ground, leaving more room for parks, walking paths, and surface streets.

Tokyo Japan's Bridges: Metropolitan Expressway #7 Bridges across the Kyu Nakagawa by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Tokyo, Japan's Bridges: Momiji & Sakura Bridges across the Kyu Nakagawa (7)

March 2012 (35.693 Degrees, 139.848 Degrees) Sakura Bridge

A final look back at the Sakura and Momiji Bridges. I hadn't noticed before but the striped concrete triangles on the river piers are on opposite sides of the two bridges. Also, you can see that the river piers are much more elaborate than the piers on the opposite embankment. Finally, I noticed that those corbel things are only on one side of the bridge (on the outside girders facing the other bridge).

Tokyo, Japan's Bridges: Momiji & Sakura Bridges across the Kyu Nakagawa (7) by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Tokyo, Japan's Bridges: Momiji & Sakura Bridges across the Kyu Nakagawa (6)

March 2012 (35.693 Degrees, 139.848 Degrees) Sakura Bridge

A look at the slope paving, a pier on the embankment, and the girders under the Sakura Bridge. The bays between the girders are painted a darker color, they have trays in every other cell, and they carry a variety of utilities. It appears that each box girder is supported by a single pot bearing and it also looks like they may be doing some work at the pier.

Tokyo, Japan's Bridges: Momiji & Sakura Bridges across the Kyu Nakagawa (6) by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Tokyo, Japan's Bridges: Momiji & Sakura Bridges across the Kyu Nakagawa (5)

March 2012 (35.693 Degrees, 139.848 Degrees) Sakura Bridge 

A view of the decorations on a pier of the Sakura Bridge. It looks like the pier was built of alternating courses of smooth and rough faced masonry blocks with a striped concrete overlay covering part of the wall. Or perhaps the whole thing was produced using elaborate forms around poured concrete?

Note that the bottom of the pier has been stained by the different water levels of the river. I guess there's not much a designer can do about stains other than making the pier the same color so it's less obvious.

The striped concrete makes a triangle across one side of the pier while the sunlight creates a triangle on the opposite side of the pier. Was it the designer's intention to imitate the sun shining on the pier.

The striped concrete appears to overlap at the bottom, similar to a patty of cooked rice partially wrapped in seaweed. However, everything reminds me of food.

Tokyo, Japan's Bridges: Momiji & Sakura Bridges across the Kyu Nakagawa (5) by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Tokyo, Japan's Bridges: Momiji & Sakura Bridges across the Kyu Nakagawa (4)

March 2012 (35.693 Degrees, 139.848 Degrees) Sakura Bridge

A closer view of the Sakura Bridge with its lampposts like dragonfly wings. I wonder if the corbels between the deck and the girders are purely decorative or serve a purpose?

Tokyo, Japan's Bridges: Momiji & Sakura Bridges across the Kyu Nakagawa (4) by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Tokyo, Japan's Bridges: Momiji & Sakura Bridges across the Kyu Nakagawa (3)

March 2012 (35.693 Degrees, 139.848 Degrees) Momiji and Sakura Bridges

Another view of the Momiji and Sakura Bridges across the Nakagawa. The bridges are three span haunched steel box girder structures on decorated pier walls. Just as the nearby buildings seem to capture the salmon color of the girders, the pair of bridges in the background seem to capture the light grey color of the bridges' piers.

Also note the parallel image of each bridge in the water. Bridge designers should consider the reflected shape of their river crossings to create a pleasing double image.

Tokyo, Japan's Bridges: Momiji & Sakura Bridges across the Kyu Nakagawa (3) by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Tokyo, Japan's Bridges: Momiji & Sakura Bridges across the Kyu Nakagawa (2)

March 2012 (35.693 Degrees, 139.848 Degrees) Momiji and Sakura Bridges

We are back at the Momiji and Sakura Bridges. This is a pretty area of Tokyo between the Arakawa and the Nakagawa. The two bridges are part of a big oval track used by mothers pushing strollers (along with runners and bicyclists).


I like how the bridges are the same color as the buildings behind them. I also like the reflections of the bridges in the water. We are far enough away from downtown Tokyo so the landscape architects had a larger canvas to work on. The only blemish is the two buildings covered in the ubiquitous blue tarp.

Tokyo, Japan's Bridges: Momiji & Sakura Bridges across the Kyu Nakagawa (2) by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Tokyo, Japan's Bridges: Funabori Bridge (船堀橋) across the Nakagawa

March 2012 (35.691 Degrees, 139.848 Degrees) Funabori Bridge

The Funabori Bridge crosses the narrow Nakagawa and then continues east across the wide Arakawa as we saw in the blog of May 26th and June 4th. See Google Earth Photo below for location of Funabori Bridge just below the oval walking path and just above the Higashi Ojima train station Bridge across the Nakagawa. The bridge carries Route 50 with four traffic lanes and two sidewalks.

Tokyo, Japan's Bridges: Funabori Bridge (船堀橋) across the Nakagawa by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Tokyo, Japan's Bridges: Higashi Ojima Eki Bridge over the Kyu Nakagawa (2)

March 2012 (35.690 Degrees, 139.848 Degrees) Higashi Ojima Station Bridge

Back to the Higashi Ojima Bridge/Train Station that we last visited at the start of our canoe trip on June 3rd. I was recently reading about homes and businesses crowded onto bridges, but now I can't remember where. I did find a website that addresses buildings on bridges, but it wasn't the one I was reading. Still it is an interesting website with lots of good photos of bridges carrying buildings. I don't quite get what's the advantage of putting your home or business on a bridge though.

Tokyo, Japan's Bridges: Higashi Ojima Eki Bridge over the Kyu Nakagawa (2) by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.