P/E MARKET: High-tech bridge inspections

March 10, 2011

The Maine Department of Transportation (MEDOT) has one of the most robust underwater bridge inspection programs in the country. In order to comply with state and federal inspection requirements, a 12-person professional dive team conducts bridge inspections on every bridge that relies on underwater structural support. Of the state’s 3,000-plus bridges, more than 500 require underwater inspections.


The Maine Department of Transportation (MEDOT) has one of the most robust underwater bridge inspection programs in the country. In order to comply with state and federal inspection requirements, a 12-person professional dive team conducts bridge inspections on every bridge that relies on underwater structural support. Of the state’s 3,000-plus bridges, more than 500 require underwater inspections.

But strong currents and restricted visibility often create difficult and even dangerous conditions for the divers. As a result, MEDOT turned to a high-tech alternative: hydrography. Substructure Inc., Portsmouth, N.H., conducted high-resolution multibeam surveys of three bridges that span the Kennebec River in Bath and Richmond, Maine. Initial “baseline” surveys were completed in June 2009, and follow-up “current-conditions” surveys were conducted in July 2010 to obtain comparative hydographic survey and scour data.

Before each survey, Substructure established a real-time kinematic (RTK) differential global positioning system (DGPS) base station over a known control point to ensure high resolution, accuracy and consistency. From there, the company’s custom-made vessel, the Orion, conducted the surveys using a host of high-tech equipment, including an R2Sonic 2024 and Reson 8125 multibeam echo sounders. In addition, Orion was equipped with an Applanix 320 POSMV vessel motion re7ference and navigation unit, Odom Digibar speed of sound profiler and Hypack/Hysweep hydrographic data acquisition and processing software.

During the actual surveys, the multibeam transducer was rotated outward 30° so data could be acquired almost up to the water surface. This let Substructure maximize data coverage around the structural supports. The data collected from the surveys is useful for depicting overall bathymetry around the site and also shows a general outline of the bridge supports.

Additionally, Substructure was able to create numerous high-resolution point-cloud datasets of all of the valid multibeam soundings around each structural support.

While the acoustic surveys were not meant to replace periodic “hands-on” inspections, the new method provided a quick, easy and safe way to monitor erosion and depositional changes over time.

Brushless breaker

The Hilti TE 3000-AVR is an electro pneumatic breaker that boasts the power of an air tool, at the same weight level, without the need for an air compressor. It weighs 65 lb and delivers 50 ft-lb of impact energy, making it ideal for heavy breaking applications and demolition work at floor level. An active cooling system reduces wear and tear on the motor, electronics and hammering mechanism. The breaker also features a brushless SR motor, which doubles the expected motor life. It also has several vibration-reduction features to reduce operator fatigue.

Cut longer

Husqvarna’s newest power cutter, the K970, features a cleaner, more powerful and more fuel-efficient X-Torq engine. It also was ergonomically designed for the operator. A softer rear handle allows for better grip and hip support, and a vibration dampening system reduces fatigue and extends cutting time. The Active Air Filtration system helps minimize motor wear and extends filter life, while a dust-sealed starter, air purge and decompression valve ensures easy and reliable starts.

Three generators

The SGX line of generators, from Subaru, is available in three models to meet the needs of numerous users, from home­owners to contractors. The SGX3500 utilizes the company’s EX21 7-hp engine, and the 4-gal fuel tank provides eight hours of continuous run time. The SGX5000 uses a 9.5-hp engine and the 7-gal tank allows 9.4 hours of continuous run time. The largest, the SGX7500E, runs on a 14-hp engine that produces 7,300 watts and can operate for seven straight hours. All are made of heavy-duty steel.

Several options

The new Road Wizard mechanical sweeper from Elgin Sweeper has an array of chassis to choose from, including Freightliner, UD, International, conventional or cabover. The sweeper is powered by a liquid-cooled, low-emission Tier IVi engine that provides variable control over sweeper speeds without affecting truck speed. The 132-in. wheelbase results in a 9-ft sweepable inside radius and a 25-ft sweepable outside radius, making it ideal for heavy municipal and construction applications. The redesigned sweeper also has three water tanks, eliminating the need for baffles and boosting capacity to 360 gal.

Electric lifter

By utilizing AC motors and transistor controller technology for both the traction and hydraulic systems, the Hyster E30-40XN electric lift truck reduces maintenance costs. It delivers a lifting capacity of 3,000 to 4,000 lb and can perform in a wide variety of material-handling applications. The Hyster-designed thermal management system continuously monitors controller and motor temperature and automatically adjusts truck performance to protect critical components. It also features improved break-pedal layout and an auto deceleration system that reduces operator fatigue.

Tough crusher

Inertia Machine Corp.’s new 5066 Tracker Primary HIS Crusher is engineered to deliver capacities of up to 700 tons per hour at lower costs. Since it is track-mounted, the crusher also offers trailer-free transport. The crusher features a 14-cu-yd nonheaping hopper and a large, 42- x 64-in. feed opening on the Inertia 5066 HS Impactor. The 5066 Tracker is built for the toughest, high-impact applications, such as aggregate or concrete and asphalt recycling. The machine is powered by a 400-hp John Deere Tier III diesel engine and a 125-kW generator.

Fewer cracks

The Sealate T-70/MX-30 is a specially formulated, high-molecular-weight methacrylate (HMWM) resin system. The low viscosity allows it to penetrate deep into fine cracks by gravity alone and then seal them. Once the material has cured, the high bond strength heals the cracks and restores the concrete strength to reduce crack propagation.

Low tail swing

With its near-zero tail swing, the Doosan DX235LCR crawler excavator can work next to buildings and in confined spaces without sacrificing performance or stability. The excavator’s 3.75-in. tail swing means that it can work on roadways and rail lines without blocking traffic. A power boost increases the bucket and arm breakout force by about 5%, making it the highest of any excavator in its class, and it can reach a max of 32 ft 3 in. The machine is designed to be quiet, since the noise level at the operator’s ear is only 71 dB(A), and at ground level it is 103 dB(A).

Gas detector

The Altair 4X Multigas Detector operates with only MSA XCell Sensors for combustible gas, O2, H2S and carbon monoxide (CO). It is compatible with the Altair 4 Galaxy Test Stand and provides exclusive optional MotionAlert and InstantAlert features. It also has a standard three-year warranty, four-year sensor life, faster response time, increased stability and its calibration takes less than 60 seconds.

Cool helmet

Gateway Safety’s Serpent Ventilated Safety Helmet offers maximum head injury protection while also helping minimize heat buildup under the helmet’s shell. The CoolSense airflow system, along with six vents along the peak of the helmet, helps release heat and keep workers cool. This helps prevent workers from overheating or becoming fatigued. A brow pad also absorbs moisture and perspiration. The helmet weighs just 13.1 oz and adjusts to fit 65?8- to 81?4-in. head sizes.

Ergonomic eyewear

The new Smith & Wesson 44 Magnum line of protective eyewear, from Kimberly-Clark Professional, is designed to be stylish, safe and comfortable for maximum compliance. They were created with several ergonomic features for long-term performance and all-day comfort. For example, they are made of a cut-to-shape, distortion-free, one-piece lens. Also, the nosepiece is flexible and easily conforms to different nose shapes. Vents on the temples also help increase airflow. They are available in several lens tints for different light settings.

Brighter light

The Furyo, by Schreder Lighting USA, uses the Philips CosmoPolis lamp and ballast system to offer a high-tech light alternative. It features an IP66-rated Sealsafe optical unit with easy access, and the body is constructed with a self-cleaning protector made from tempered glass. A multilayer HIR reflector also increases luminance by 20% compared with current anodized reflectors. Maintenance time is reduced to a minimum, since the lamp can be accessed safely and quickly from the front without tools.

Sponsored Recommendations

The Science Behind Sustainable Concrete Sealing Solutions

Extend the lifespan and durability of any concrete. PoreShield is a USDA BioPreferred product and is approved for residential, commercial, and industrial use. It works great above...

Proven Concrete Protection That’s Safe & Sustainable

Real-life DOT field tests and university researchers have found that PoreShieldTM lasts for 10+ years and extends the life of concrete.

Revolutionizing Concrete Protection - A Sustainable Solution for Lasting Durability

The concrete at the Indiana State Fairgrounds & Event Center is subject to several potential sources of damage including livestock biowaste, food/beverage waste, and freeze/thaw...

The Future of Concrete Preservation

PoreShield is a cost-effective, nontoxic alternative to traditional concrete sealers. It works differently, absorbing deep into the concrete pores to block damage from salt ions...