A memorial for the 361 miners who died in the worst mining disaster in America’s history. Credit: Associated Press
Mining is one of the most dangerous occupations there is. Every year, hundreds of miners die in accidents from collapses, explosions, and fires. The good news is that mining accidents and the deaths associated with them have declined drastically in the past 40 years, and even more so in the past 100+ years. The bad news is that mines are still highly dangerous. According to the MSHA (Mine Safety and Health Administration), 1907 was the “deadliest year in U.S. coal mining history…when an estimated 3,242 deaths occurred.” In that year, 361 people were killed in the United States’ worst mine explosion ever, near Monongah, West Virginia. In May of this year, 301 miners were killed in Turkey’s largest mining explosion, which is especially alarming considering the upgraded mining health and safety regulations that have been established and improved upon since the 1970’s.
Mining disasters have declined significantly since the industry started. Credit: MSHA.gov
A “mining disaster” refers to a mining incident which kills 5 or more people. From 1976 to present, fewer than 20 total mining disasters have occurred in the United States, compared with 526 mining disasters that occurred between 1901 and 1950. Statistics from MSHA and other government agencies show that U.S. mining fatalities and accidents in general have declined significantly, but accidents still occur alarmingly frequently in other parts of the world. China remains one of the deadliest mining countries, resulting in more than a thousand deaths last year, despite recent safety gains. China also claims the deadliest mining disaster in the world’s history, having killed 1,549 miners in April, 1942. But recent mining events are prevalent, too. For example, Chile’s 2010 mining accident trapped 33 miners underground for 2 weeks (luckily, 31 of them survived). Just two weeks ago, 5 miners died in a mine collapse in Bosnia, and in August, another 25 passed away in a rebel-held mine in the Central African Republic town of Bombari. Several other mine accidents have occurred in the past decade, many of them this year.
Corroded columns like these can mean disaster for a mine.
So is there anything that can be done to make the world’s mines safer? As a matter of fact, there is. At HJ3, we’ve helped improve the safety of several mines in the Southwest United States by strengthening their concrete and steel structures. Many modern mine collapses are due to vibrations from large equipment, so strengthening their support systems can drastically reduce the risk of collapse from these vibrations. Many of the world’s mines are over 100 years old, and the concrete beams and columns that support them have corroded due to the constant exposure to vibration, moisture, sulfuric acid, and the mines’ own elctrowinning processes.
A corroded column (left) is restored with HJ3’s CarbonSeal system (right).
Some of the mines that HJ3 has reinforced were so badly degraded that they risked being shut down by MSHA. With a layer of CarbonSeal™’s glass composite and carbon fiber fabrics, the columns and beams in these degraded mines have been restored, providing greater strength than the mines have seen in the past 100 years. Since HJ3’s composite systems are 1o times stronger than steel and highly chemical-resistant, they’re ideal for reinforcing corroded structures that are exposed to harsh mining conditions. And since the systems come as a lightweight, flexible fabric, they’re ideal for narrow or otherwise difficult-to-get-into spaces.
Do you know of a mine that could use some structural strengthening? Join HJ3 in our quest to save lives and resources everywhere! Contact us at email@example.com for more information.
A gas explosion in Harlem earlier this year killed 8 and injured 48. Credit: NY Daily News
Gas Pipeline explosions in the United States have occurred at an alarming rate, especially in the past 10 years. Every other day, a gas leak destroys property, injures several people, and sometimes kills others. The decade’s most catastrophic explosions have claimed more than 135 lives, injuring 600 others and racking up a $2 billion bill from damages. The main culprit? The old, corroded gas pipelines that weave their way beneath America’s cities.
Cast iron and bare-steel pipes tend to catch most of the blame for the gas leak explosions, and rightfully so. Many of the pipes that feed natural gas to more than 67 million homes, schools, and businesses across the United States are over 100 years old. Cast-iron and unprotected steel are very susceptible to rust and corrosion, and the older the pipe is, the greater the likelihood of a leak. And when leaking gas from one of these pipes accumulates in a building or basement, it can explode with an earthquake-like force, instantly. Considering that more than 85,000 miles of cast-iron and bare-steel gas pipes are still in operation, much of it concentrated in heavily-populated areas like New York, Boston, and Detroit, something needs to be done to prevent more devastating explosions.
Corroded cast-iron gas pipe. Credit: San Diego.gov
But what? The Pipeline and Hazardous Materials Safety Administration has been urging gas utilities to replace their aging pipes for decades. While replacement efforts are underway for many cities, they’ve proven to be slow-going and very expensive. From 2004-2013, 10,000 miles of cast-iron pipe, and 17,000 miles of bare-steel pipe have been replaced, but a daunting amount remains: 30,000 more miles of corroded cast-iron and 56,000 miles of bare-steel pipe still need replacement. Utility companies in New York plan to replace their aged pipes with a more corrosion-resistant material like plastic, at a rate of 65 miles of pipeline per year. The cost of this replacement is estimated to be about $215 million per year, with a grand total price tag of $10 billion to replace all of the aged pipes. Pensacola, Florida, has 4 times the national average of cast iron and bare-steel pipelines, and they plan to replace some 20 miles per year; if they follow that schedule, the work won’t be finished until 2067. At that point, more pipeline will have corroded and need to be replaced as well.
Considering the astronomical costs associated withe replacing these pipes, I can’t help but wonder where all that money is going to come from. As it stands, the United States alone faces a $6 trillion degraded-infrastructure deficit, and that deficit will only climb as time passes and more pipelines and other structures continue to corrode. What America really needs is an alternative methodto pipeline replacement.
A natural gas pipeline is repaired with HJ3’s carbon fiber systems.
A gas pipe wrapped with HJ3’s CarbonSeal system withstood a 5200 PSI blast test
And luckily for us, there is an alternative, and it costs a whole lot less than replacement. Enter HJ3, The Strongest Name in Carbon Fiber™. Our CarbonSeal™ system has already successfully repaired several corroded gas pipelines, providing an extra 30 years of service life and a strength that’s 10 times greater than steel. By simply wrapping the corroded pipelines with our patented carbon fiber systems, we’ve helped several utility companies save millions of dollars and months of downtime. Since carbon fiber is corrosion-resistant, it requires no maintenance after being installed, and since it’s a flexible fabric, full excavation and pipe removal isn’t necessary. In burst tests, a CarbonSeal™-wrapped pipe successfully withstood 5200 PSI; typical pressures in a gas pipeline range from 200-1500 PSI. If HJ3’s carbon fiber systems are used to repair just a small fraction of the corroded pipelines in America, we can reduce the risk for explosion, potentially saving valuable lives and preventing catastrophic damage everywhere.
Want more information about HJ3’s carbon fiber systems and how they can save you 60-90% versus pipeline replacement? Contact us today at firstname.lastname@example.org.
Many thanks to USA Today, who inspired this blog and indirectly contributed information via their 9/24/14 article, “Danger Under Our Streets”.
Bridges are an essential part of transportation infrastructure everywhere. But as they age, bridges have a tendency to corrode from de-icing salts, carbon dioxide in the atmosphere, and water seeping in through tiny cracks. While this corrosion is very dangerous, and can lead to a bridge’s collapse, the damage is often only visible at a very advanced stage, usually creating a very expensive repair bill. If only there was a way to detect corrosion before it reached this advanced stage…oh wait, there is?
Yes, actually, and it’s been in use for the last 25 years. The process involves a device with an electrode attached to a wheel, which, when rolled across the surface of reinforced concrete, measures the concrete’s potential difference. Large differences indicate that the steel rebar within the concrete in those areas has already started to corrode. The problem with this technology is that the wheel is attached to a stick, and then rolled manually over the concrete surface, which means that many areas, such as the supporting pillars and undersides of high bridges, remain out of reach.
C2D2, a corrosion-detecting robot, was developed in Switzerland. Credit: Swiss Federal Institute of Technology (ETHZ)
To solve this problem, a team from Switzerland’s Institute for Building Materials joined forces with the Institute of Robotics and Intelligent Systems. Their goal was to develop a robot that could detect corrosion in all areas of a bridge, especially those that are inaccessible to humans. Furthermore, they wanted their robot to be able to detect corrosion at its earliest possible stage, thereby reducing the repair bill and the likelihood of a future collapse. To accomplish this goal, they built a robot that could not only move along the ground, but could also climb walls and traverse ceilings. The robot’s movement is based on Vortex technology, in which a propeller is attached to the underside of the robot and rotates fast enough for a mobile suction cup to stick the robot to walls and ceilings. Wheels then propel the robot along bridge surfaces, steered by a remote control.
C2D2 can climb up walls and ceilings, detecting bridge corrosion everywhere. Credit: Swiss Federal Institute of Technology (ETHZ)
The robot, which was originally named “Paraswift”, was actually designed 4 years ago, with the intention of being used by Disney for its ability to film from all angles. Now, “Paraswift” has been renamed “C2D2″ – Climbing Corrosion Detective Device. The technology is similar to the original electrode-on-a-wheel model, but this robot’s electrode is affixed to the underside of C2D2, and a pink ball with a camera is attached to the top. The camera enables the robot to record surroundings, allowing its controllers to identify and avoid potential obstacles, and the pink color makes C2D2 easier to locate. The robot has already successfully detected corrosion on a number of bridges in Switzerland, but the team has more plans before C2D2 has completely met their expectations. By mid-2015, they hope that a navigation system will replace the manual steering, enabling the robot to identify and overcome obstacles entirely on its own.
C2D2 will likely prove a very valuable tool in the fight against infrastructure corrosion, but it’s not the first robot that’s been designed for this purpose. Redzone Robotics has been building robots to inspect mid-sized sewer lines since 2013. The company’s robots find corrosion, debris, and deformations inside sewer pipes, then relay the information to operators who can dispatch maintenance crews. Rolls Royce has been making pipe-inspecting robots since 1991, and they have proven especially valuable for inspecting pipes in nuclear power plants. Other pipeline-inspecting robots have the ability to coat pipe interiors, decreasing pipeline leaks in gas and hazardous chemical pipelines. And HiBot, a Japanese robotics company, has built self-propelled robots to inspect high-voltage overhead power lines for internal corrosion.
The HJ3 Civil carbon fiber system is great for repairing corroded bridges.
It’s no mystery that corrosion is destroying the world’s infrastructure. Unfortunately, as more structures continue to corrode, our available funding to repair them can’t keep up, and our $4 trillion spending gap grows. But with continued technological developments like C2D2 to detect corrosion early, and HJ3’s Civil carbon fiber systems to repair corroded bridges before they collapse, we’re working towards closing that spending gap, one bridge at a time.
If you’d like more information about HJ3’s carbon fiber systems and how they can save you money on corroded bridge repairs, write us today at email@example.com.
The Nacimiento Pipeline is 45 miles long and provides water to 5 California communities. Photo Credit: San Louis Obispo County
The Nacimiento Water Project, touted as “the saving grace to many local communities’ dwindling water supplies” is a $176 million project designed to increase water supplies for 5 communities within San Louis Obispo County in California. The project includes a 45-mile water pipeline that carries water from Nacimiento Lake to Atascadero, Cayucos, Paso Robles, San Louis Obispo, and parts of Templeton, and was finished being built and installed in 2010. Since its initial installation, however, the pipeline has already been shut down three times due to leaks, dents, and collapse; the most recent shutdown has taken the pipeline out of commission since June of this year, resulting in a lack of water from this source for all five communities for most of the summer.
The pipeline was shut down after county workers noticed that water was seeping up onto an access road near the Nacimiento River. San Louis Obispo County hired excavators and divers, who dug 20 feet underground and cut into the 30-inch diameter pipeline, using a video camera to find the source of the leak. After patching that leak, the pipe still failed a subsequent pressure test, encouraging investigators to look for more leakage. They found at least 5 more cracks in the pipe. The cause of the cracks is yet to be determined, but authorities have narrowed it down to three possibilities: faulty material used in the construction of the pipeline, a problem with the welds, or damage incurred while actually installing the pipeline. Investigations are currently ongoing, but county officials say they have found a temporary repair method that should get the pipeline running again while they determine a more permanent solution. Since July, 2014, the county has spent $134,000 on emergency contract work to investigate the problem, but at this point, the leaks are small and not causing any serious issues. Additionally, any water that leaks out goes directly into the Paso Robles Groundwater Basin.
Nacimiento Lake feeds the 45-mile pipeline. Photo Credit: San Louis Obispo County.
While the pipeline has been billed as the “largest public works project ever”, designed to provide millions of gallons of drinking water to the communities, its shutdowns have prevented communities the additional water supply they were promised. And considering the drought that California has endured this year, now is the time that they need that water the most. But since the lake is only one of several sources that provides the area with water, County District Supervisor Frank Meacham seems more concerned about water supplies to cover next year’s drought: “the concern is going into the next year, and if there’s another year of drought, will we have enough water at that point?” Prior to June’s shutdown, the city had been using the pipeline water allocations to recharge wells, filtering the lake water into pooling systems on top of the Salinas riverbed to offset summer shortages. The lacking ability to follow that same process this summer, combined with the lake’s significant water level drop, has resulted in Meacham’s (and others’) concerns.
This latest leak comes as yet another piece of bad news that has seemed to follow the pipeline since its inception. During construction, 3 pipeline workers were killed in two different incidents. In August, 2010, a segment at the pipeline’s intake site at Nacimiento Lake collapsed, forcing an 8-month shutdown just after it was completed, and later, the pipeline was shut down again due to a dent and subsequent rupture that occurred in a segment near Santa Margarita. Clearly, the project needs a permanent, reliable solution to prevent any more shutdowns.
The HJ3 Civil System repaired this steel drinking water pipe in a matter of hours.
HJ3 is able to provide that solution. Our patented carbon fiber has already repaired thousands of feet of pipeline, often in emergency repair situations. And considering that our systems meet NSF 61 standards for potable water, they’re completely worry-free. Once applied, HJ3’s systems are resistant to corrosion and chemicals, requiring no future maintenance or excavation whatsoever. And they install quickly and easily; in another California county, HJ3 was called upon to fix a steel drinking water pipe that had corroded to the point of developing through-holes. Rather than replacing the entire section of pipe, HJ3’s Civil™ system successfully repaired the degraded pipe in just a few short hours.
This large-diameter PCCP was successfully repaired with the HJ3 Civil carbon fiber system.
And in Miami, HJ3’s Civil™ system also repaired more than 750 linear feet of corroded PCCP in only 3 days, where 7 sections of pipe in their sewer system were found to be leaking. Not only did the city prevent 2 weeks of downtime from having to excavate, remove, and replace the damaged pipe, but they also saved $1 million by repairing the PCCP with carbon fiber instead. Furthermore, repairing water pipelines instead of replacing them prevents hundreds of thousands of gallons of water from being wasted, several tons of carbon dioxide emissions from polluting our atmosphere, and tons of steel and concrete from filling our landfills due to the production of new pipeline.
If you want more information about HJ3’s Civil™ systems and how they will repair your own problematic pipelines, write us today at firstname.lastname@example.org.
September is National Preparedness Month, which is convenient considering the extreme weather disasters that we’ve been struck with this summer. FEMA, NWS, and NOAA have compiled a handy checklist to help you and your family prepare for extreme weather. We can’t outsmart Mother Nature, but we can be aware of what she’s doing and prepared for whatever she throws at us.
Build a Kit. Have basic food, water, and first aid supplies in a prepared kit that can be stored and easily found if an emergency is imminent.
Prepare Medications. Stock enough essential medications to last 3-5 days, and pack them ahead of time.
Have a Radio and Extra Batteries Handy. When the power is out, you’ll still want to be informed about the conditions outside. A solar-powered cell phone charger might be a good idea, too, but keep in mind that cell phone reception will likely be minimal.
Make copies of important documents. Make copies of such documents as birth certificates, insurance policies, and other personal papers to time-sensitive documents in case the originals are destroyed.
Inform Everyone of your Plan. Every immediate family member should have clear instructions of the emergency plan. Make sure to also inform a relative or family friend who is not in the nearby area.
Keep Extra Cash on Hand. If the power goes out, ATM’s and credit card machines probably won’t work. Have some emergency cash in your kit or readily available.
Fill Up your Gas Tank. In extreme cases, gas supplies can be limited. If a storm is approaching, fill up ahead of time in case you need to evacuate.
Less than a week after Hurricane Norbet took its toll on Baja California and the Southwest United States, Hurricane Odile has swept through the same area, causing major damage and flooding for many parts of Mexico. And now, it’s on its way to the same area that was drenched in record-setting floodwaters just last week. And in the midst of cleaning up after these two hurricanes, Hurricane Eduoard on the Atlantic Coast has strengthened to a Category 2 hurricane of its own. While Eduoard is expected to stay far out into the ocean, posing no potential threat to land, one thing is clear: Hurricane Season is upon us.
Hurricane Norbet was the 10th hurricane of 2014. It is responsible for at least 5 deaths in Mexico and the United States, and damage reports have estimated the total economic losses in the US and Mexico to exceed $100 million. It reached its peak intensity on September 6, when it was a Category 3 Hurricane with 120-mph winds that tattered coastal Mexican cities like San Carlos. Record-setting rainfall drenched Phoenix and surrounding areas.
Destruction from Hurricane Odile. Credit: BBC News
Hurricane Odile has seemed to follow in Norbet’s footsteps, bringing 125-mph winds when it landed near Cabo San Lucas. Thousands of tourists and locals were forced to hunker down in luxury hotels that were converted into shelters. And even then, some shelters were destroyed by winds, forcing those people into hotel stairwells for several hours. Hundreds of homes have been destroyed, especially in poorer neighborhoods, and some hungry citizens are looting grocery stores for food and other goods. Trees and power lines were knocked down throughout Cabo San Lucas, and nearly 239,000 people are without power. But while 30,000 tourists have been put up in temporary shelters and 135 minor injuries have been reported, Hurricane Odile has luckily not taken any lives or caused any serious injuries.
Hurricane Odile weakened to a Category 1 on Monday, and then downgraded to a tropical storm on Monday night, but dangerous flash floods and landslides are being warned for the Southwest United States. Some 6-12 inches of rain could fall between Wednesday morning and Thursday night in southern Arizona, with 10 inches or more possible on mountain slopes.
A few years ago, HJ3 was featured on the Discovery Channel’s hit show, SmashLab. On the show, a mobile home was wrapped with HJ3’s carbon fiber and put up against Category 5 hurricane winds. The winds were so strong that they forced the mobile home off of its anchors, sending it tumbling; what’s truly remarkable is that even while it’s rolling, the mobile home stays fully intact. HJ3’s carbon fiber really is strong enough to prevent a house from falling apart in strong hurricane winds! But don’t just take my word for it, check it out for yourself!
HJ3 has been strengthening corroded bridges with carbon fiber for a while now, and the results have been impressive. Throughout the years, carbon fiber has really proven itself to be an innovative rehabilitation material, but we never seem to hear about bridges that are actually constructed with carbon fiber reinforced polymers (CFRP). But why? It seems logical that if reinforced concrete structures could be protected from corrosion right off the bat, the structure’s life expectancies should surpass 70 or 80 years, doubling or even tripling the life expectancies of current designs, right? So have we not heard of these bridges because they don’t yet exist? Well, as it turns out, there are several bridges all over the world that were initially constructed with CFRP materials.
CFRP cable strands and tendons were used in the construction of the Bridge Street Bridge. Credit: michigan.gov
The first CFRP bridge to be built in the United States was the Bridge Street Bridge (aptly named, don’t you think?), in Michigan. It was designed and built by researchers at Lawrence Technical University in 2003, and replaces traditional black steel reinforcement with a combination of stainless steel and carbon fiber materials. The carbon fiber components include both straight and bent bars (for non-tensioned reinforcement), as well as pre-tension carbon fiber strands (used in a manner similar to steel pre-tensioning strands in concrete beams), prestressing CFRP tendons and non-prestressing carbon fiber composite cable strands (to replace steel bars and tendons), as well as carbon fiber mesh fabric. 11 years after its construction, Michigan governor Rick Snyder has commended the success of the bridge, referring to it as “the bridge of the future.”
Lifting the CFRP bridge deck into position took less than 30 minutes. Credit: fiberline.com
CFRP bridges are also prevalent in Europe. While many of them are footbridges, used primarily for pedestrians and bicyclists, their success will likely transition into more road bridges in the near future. One such road bridge, The West Mill Bridge, in Oxford, UK, has been described as “one of Europe’s most advanced highway bridges” for its CFRP construction, even though it’s only 10 meters long.
The West Mill Bridge is “one of Europe’s most advanced highway bridges” Credit: Composites UK
Built in 2002, the bridge utilizes composites in its load-carrying beams, side paneling, and bridge deck. The bridge’s edge beams, footpath, and two crossbeams at each end are constructed of concrete, while its crash barrier is made of steel. The wearing surface itself is actually a polymer concrete as well. All load-carrying elements are made from polyester, glass, and carbon fibers, and the entire bridge was built at a temporary factory, located at the bridge site. After construction was finished, it took less than 30 minutes to lift it and set it into position. Building a bridge with CFRP components comes with several advantages:
Short construction phase
Resistant to water, de-icing salt, and frost
Much longer service life
Minimal maintenance costs
Low operation costs
Less traffic problems due to maintenance
Reduced mass, allowing for smaller cranes, simplified transportation, easier installation, and reduced assembly time and cost
Resistant to chemicals from spillages
New aesthetic possibilities
More efficient geometrically
Want more information about using carbon fiber for bridge repair or construction? Email us today! email@example.com
Corrosion has been blamed for an oil spill that occurred in Wyoming this past May. A backhoe initially nicked a 6-inch underground pipeline, which, over time, resulted in corrosion until the pipeline eventually ruptured. Reports indicate that it’s unclear just how much time passed between initial backhoe damage and when the spill actually took place. 25,000 gallons of crude oil were spilled into the ground in Wyoming’s Powder River Basin, traveling for more than 2 miles before being blocked by a temporary dam, which was put in place to prevent the spill from pouring into the Powder River.
The 25,000 gallon crude oil spill was cleaned up by burning. Credit: kansascity.com
Cleanup efforts “went very well,” according to Bureau of Land Management environmental coordinator Bob Dundas. Initially, the BLM was planning to use vacuum trucks to clean up the spill from the Casper-based Belle Fourche Pipeline, but later decided that burning the spill was a more efficient disposal manner.
The spill is reported to have occurred on federal and state-owned land; no private property was affected. Even though high levels of petroleum remained in the soil for a few weeks following the spill, area groundwater is also said to have been uncontaminated.
While this spill isn’t exactly a disaster, per se, it could have been prevented. After the back-hoe nicked the pipeline, a simple repair would have prevented the corrosion which lead to its ultimate demise. And while traditional repair methods are costly and time consuming, often requiring steel welding and/or total replacement, there are other options available that don’t require replacement at all.
HJ3’s CarbonSeal system is perfect for pipelines of all sizes. Here, a natural gas pipeline has been repaired with HJ3’s carbon fiber.
HJ3’s CarbonSeal™ carbon fiber repair systems provide an innovative approach to repairing nicked or otherwise damaged pipelines. Carbon fiber composites are approved by the American Society of Mechanical Engineers (ASME) in their standard for repairing pressure equipment and piping. Carbon fiber is actually 10x stronger than fiberglass systems, so less material is needed. The installation is quick, requiring only minimal downtime. And the overall price is competitive. ASME/PCC-2 compliant HJ3 Composite Technologies CarbonSeal systems have been used to repair thousands of linear feet of pipe since the original standard was created in 2008. HJ3’s systems in particular save owners up to 90% on repairs compared to replacing their pipe.
Pipeline ruptures are preventable. As more and more oil refineries and individuals become aware of carbon fiber repair options, spills like this one will become less and less prevalent, but regular inspection of pipelines is key to providing a solid solution.
Want more information about repairing your corroded pipelines? Email us at firstname.lastname@example.org.
Flooding along Arizona’s highways caused road closures and significant damage. Credit: AZCentral.com
On Monday, Southern Arizona experienced its wettest day in recorded history. Remnants from Hurricane Norbet mixed with pre-existing monsoon humidity to cause more than 3.25 total inches of rainfall in one day. The region typically sees 2.71 inches of rain for the entire monsoon season, but on Monday alone, 2.96 inches had already fallen by 8:30 am, and the downpour didn’t let up all day. Two people were killed while trying to escape the rushing waters, and more than 10,000 homes and businesses were left without power. Whole sections of interstates were washed away in Phoenix, and here in Tucson, high waters in the Santa Cruz River have threatened the structural integrity of all bridges along that river. The damage from Monday’s flood continues to mount as saturated soils create instability all around us. And as the damage climbs, so does the repair bill. On top of the countless homes and businesses that will have to be restored, bridges and entire sections of road will have to be rebuilt. But this isn’t the first time that floods have caused so much damage to our transportation infrastructure, and sadly, it won’t be the last.
A bridge collapses in California during a massive flood. Credit: redding.com
In 1927, a flood in Vermont killed 84 people, left another 9,000 homeless, and destroyed 1,250 bridges. An 1891 flood in Arizona collapsed a railroad bridge across the Salt River, causing provisions to run short during the 3-month repair process. A 20-day flood in Oregon and Northern California in 1964 killed 19 and destroyed more than 20 major highway and county bridges, causing hundreds of millions of dollars in damages. But while many of these disasters occur without warning, preemptive efforts can prevent such terrible damage to our infrastructure.
Severe corrosion on the bridge columns.
One DOT recently decided to use carbon fiber to preemptively strengthen one of their highway bridges. Tiny cracks had developed as a result of vibrations from daily traffic passing overhead. Over time, water and oxygen had seeped into the cracks, causing them to expand and corrode the concrete and reinforcing steel rebar within. The bridge had more than 60 corroded concrete columns; the columns were so corroded, in fact, that whole sections of concrete had fallen off, exposing corroded rebar all along. The DOT realized that their bridge would collapse if something wasn’t done to strengthen it soon. They chose to repair the bridge with HJ3’s carbon fiber. Before installing the HJ3 Civil™ system on the bridge columns, all the damaged concrete was removed with chipping hammers. The exposed rebar was cleaned to near-white and protected. Wood forms were constructed around the columns to encase a high-strength grout that was poured in place. Finally, the resurfaced columns were primed, wrapped with HJ3’s carbon fiber fabric, and layered with a protective topcoat.
Restored columns are strong and corrosion-free.
The HJ3 Civil™ system successfully restored the columns’ shear and tensile capacities in only three weeks. The DOT saved 50% compared to replacement costs, and the entire repair was completed with minimal road closures. Thanks to HJ3’s system, the bridge is now corrosion-resistant, preventing the need for future maintenance. Furthermore, repairing their bridge instead of replacing it saved months of downtime, as well as preventing more than a million gallons of water from being wasted in the construction of new columns.
If you have a bridge that requires strengthening, let us know! Shoot us an email at Info@hj3.com.
Manholes are often overlooked by the common passerby, but their importance to the every-day workings of society shouldn’t be. The EPA estimates that there are about 20 million manholes in the United States – that’s about one manhole per every 400 feet of pavement! While manholes are most commonly used for allowing access to sewer lines for maintenance and repair, they are also used to gain access to water, electric, telephone, and natural gas facilities. Keeping these manholes in good condition is vital for the continued success of our cities. Unfortunately, however, many of our manholes are overlooked when sewer system maintenance is performed, which has resulted in serious decay. An estimated 20% of the manholes in the U.S. are between 30 and 50 years old, and more than 3 million are so badly degraded that they require immediate rehabilitation or replacement.
The cementitious liner that had previously been used to repair these corroded manholes in 1996 cracked and failed.
In Pima County, Arizona, 21 manholes originally built in the 1940’s had been previously rehabilitated with a competitor’s cementitious liner, which had failed. As the liner eroded, it started to lose bond adhesion to the substrate, and fragments fell into the sewage stream, threatening the county’s sewage processing system. The manholes required removal of the failed liner, strengthening, and protection from Hydrogen Sulfide Gas.
After removing the eroded liner, the surface of the manholes was sanded with a grinder. The concrete was resurfaced with Quick-Set grout, and all cracks were sealed with a low-viscosity crack injection polymer. The CarbonSeal™ carbon fiber was saturated and installed, and a vinyl ester topcoat was layered over the carbon fiber to protect it from future erosion due to Hydrogen Sulfide gas.
HJ3’s CarbonSeal™ is applied to the interior of the manholes.
HJ3’s vinyl ester topcoat will protect the manholes from Hydrogen Sulfide gas and future erosion.
HJ3’s carbon fiber system saved the county 80% compared to the cost of replacing all 21 manholes. Furthermore, since HJ3’s system repaired the manholes without causing any road closures at all, the county saved months of downtime and prevented almost 62,000 gallons of water from being wasted due to the manufacture of new manholes.
Want more information about CarbonSeal™ and how it can repair your manholes? Contact us today at email@example.com.