Industry News, trenchless projects
Hard Rock Machine crosses Finish Line Nearly Five Months Ahead of Schedule
In mid-May 2018 the national-record-setting 7.9 m (26 ft) Robbins Main Beam TBM at the Jilin Lot 3 Tunnel broke through. A formal ceremony followed to commemorate the stellar performance of the tunneling operation and its early completion. “I have participated in this project from the beginning. The project broke through 147 days earlier than scheduled. The project has achieved the fastest monthly advance rate record–1423.5 m/4,670 ft—for 7 to 8 m (23 to 26 ft) diameter TBMs in China. And the machine has reached over 1000 m (3,280 ft) per month for three consecutive months. I am so proud of these achievements,” said Mr. Wu Zhi Yong, Vice Chief Engineer and Jilin Yinsong Project Vice General Manager for contractor Beijing Vibroflotation Engineering Co. Ltd. (BVEC).
The completion of the 24.3 km (15 mi) tunnel nearly five months ahead of schedule is a monumental achievement considering the difficult ground conditions encountered. Rock types ranged from tuff to granite, sandstone, and andesite with multiple fault zones—conditions requiring nearly continuous ground support. Rock strengths varied widely from 35 to 206 MPa UCS (5,100 to 30,000 psi). The contractor cited a number of factors that contributed to the swift advance rates: “It is the stable and reliable performance of the Robbins machine, and the professional technical skills of the service technicians. The Robbins crew coordination, reasonable working progress arrangements and the sophisticated technology all allowed the project to make the fast advance rate,” said Mr. Wu.
The Robbins Main Beam TBM bored through a total of 24 fault zones utilizing a unique combination of steel McNally slats (extruded through pockets in the TBM roof shield to prevent movement of loose rock), wire mesh, and shotcrete. The TBM was specifically designed to tackle the tough conditions. “Under the variable ground conditions, especially weak, soft, and fractured rock, the optimized system and reasonable design of the machine ensured effective tunneling progress. Robbins’ unique gripper system, continuous propel system, hydraulic drives, roof support and stable cutterhead reduced the wear of cutters.The efficient belt conveyor inside the main beam allowed quick muck removal from the cutterhead to the back of the machine, which ensured the good progress of the TBM,” said Mr. Wu.
The Jilin Lot 3 tunnel is part of the Jilin Yinsong Water Supply Project, which at 736.3 km (457.5 mi) is China’s largest scale water diversion project to date. Once operational the water lines will divert the water from Fengman Reservoir at the upper reaches of Di’er Songhua River to central regions of Jilin Province experiencing chronic water shortages. These regions include the cities of Changchun and Siping, eight surrounding counties, and 26 villages and towns under their jurisdiction. The project will optimize water resource distribution, improve regional eco-systems, and ensure better food production and water safety for the people of Jilin Province.
Image 1: The record-setting Robbins TBM broke through nearly five months ahead of schedule on China’s Jilin Lot 3 Tunnel.
Image 2: A formal ceremony revealed the Robbins Main Beam TBM during its final breakthrough in mid-May 2018.
Image 3: The 7.9 m (26 ft) diameter Robbins Main Beam TBM overcame 24 fault zones and difficult variable rock conditions to achieve a national record of 1,423.5 m (4,670 ft) in one month.
Industry News, trenchless projects
Trenchless Technology Center at Louisiana Tech University Awarded Project to Measure Styrene and Other Compounds to Capture Variation in Emissions During Pipe Rehabilitation Using the Cured‐In‐Place Pipe (CIPP) Method
(Marriottsville, Maryland, June 15, 2018) – After a careful and thorough review of multiple responses to a request for proposal to provide a comprehensive evaluation of air emissions from steam-cured cured-in-place pipe (CIPP) installations and potential impacts on workers and the surrounding community, NASSCO today announces their award of the research project to the Trenchless Technology Center (TTC) at Louisiana Tech University.
The project is Phase 2 of a larger study and calls for measurement of styrene and other organic compounds at six CIPP installation sites, representing different pipe diameters (8”, 12”, and larger), and lengths, in order to capture variation in emissions. Measurements will be conducted before, during, and after curing at the termination manhole, as well as various locations in the surrounding outside area and inside nearby buildings. Worker exposure will also be measured via personal exposure monitors. Finally, dispersion modeling will be conducted to estimate compound concentrations at a large number of locations for a wide variety of meteorological conditions. Measured and modeled concentrations will be compared to appropriate health-based action levels to determine if any potential health risks exist for workers or citizens in the surrounding communities.
Phase 1 was a four-month study on the review of published literature pertaining to chemical emissions during CIPP installations using styrene-based resins. The study, completed on April 6, 2018 by researchers at the University of Texas at Arlington (UTA)’s Center for Underground Infrastructure Research and Education (CUIRE), and the Institute for Underground Infrastructure (IKT) in Germany, found that existing studies do not adequately capture worker exposures or levels in the surrounding areas to which workers or citizens may be exposed. The team further determined that spatial variation of concentrations, and variations in concentrations with different meteorological conditions, are not well determined.
Late last year NASSCO formed a workgroup consisting of industry leaders to develop the requests for proposal for both Phase 1 and 2 and to select from the multiple responses to ensure the highest levels of integrity in the final selections. “As the NASTT representative on the workgroup for the CIPP Emission Testing project, I am delighted with the selection of TTC as the most meritorious candidate for this important research,” said Mike Wilmets, NASTT Executive Director. “For nearly 30 years, TTC has contributed novel and significant work to further the advancement of the trenchless industry. This will be an exciting assignment with definitive results and will undoubtedly have a far-reaching impact on worksite safety.”
As NASSCO’s new Executive Director, Sheila Joy shares the critical need to partner with other industry organizations for important initiative such as this. “One of my top priorities is to join forces with associations and organizations such as NASTT, WRc, WEF, NUCA and others so that we may have a unified voice and serve our industry to the best of our ability. We all share the same goal when it comes to the safety of our workers and communities, and this study is a perfect example of how unification will reveal the information we need to make smarter decisions for our industry as a whole.”
For questions or additional information, please contact NASSCO at 410-442-7473 or visit nassco.org.
Industry News, trenchless products
GSSI, the world’s leading manufacturer of ground penetrating radar (GPR) equipment, announces the new StructureScan™ Mini LT – the latest member of GSSI’s popular all-in-one concrete inspection GPR systems. With all the capabilities of previous versions of the StructureScan Mini, the new StructureScan Mini LT features a lower price point that makes it even more affordable.
Rugged, compact, and flexible, StructureScan Mini LT is ideal for locating rebar, conduits, post-tension cables, and voids. It can help identify structural elements, including pan deck and concrete cover, and can also provide real time determination of concrete slab thickness. StructureScan Mini LT is the perfect entry-level concrete inspection system, and backed by a two-year warranty.
The integrated all-in-one concrete inspection tool comes with an antenna, positioning system, and control unit combination. It features an easy-to-use interface and six-button control options. With its 1.6 GHz antenna, the StructureScan Mini LT offers superior target resolution, reaching depths of 20 inches (50 centimeters).
Featuring a rugged and compact design, StructureScan Mini LT is IP 65-rated to withstand a jobsite’s toughest conditions. Users get first-in-class data visualization with a high-resolution 5.7-inch full color display with an easy user interface and different operation modes tailored for beginner to advanced use. The StructureScan Mini LT also makes it easy to customize the data display with a variety of color adjustments. Real-time migrated data, onscreen reference markers and multiple display modes are also available. Other useful features include an ergonomic handle, positioning lasers, and 4-wheel drive.
About GSSI
Geophysical Survey Systems, Inc. is the world leader in the development, manufacture, and sale of ground penetrating radar (GPR) equipment, primarily for the concrete inspection, utility mapping and locating, road and bridge deck evaluation, geophysics, and archaeology markets. Our equipment is used all over the world to explore the subsurface of the earth and to inspect infrastructure systems non-destructively. GSSI created the first commercial GPR system over 45 years ago and continues to provide the widest range and highest quality GPR equipment available today.
Industry News, trenchless people, trenchless projects
Robbins XRE completes the First TBM-driven Tunnel in Albania
On May 3, 2018 a 6.2 m (20.3 ft) diameter Robbins Crossover (XRE) TBM broke through into an underground chamber, marking the completion of the first TBM-driven tunnel in Albania. The TBM, operated by contractor Limak, was also the first Crossover machine to operate in Europe, and bored through geology including ophiolite, sandstone, breccia and siltstone flysch.
“The cutterhead and cutters have achieved outstanding performance,” said Engin Gur, TBM Manager for Limak. The TBM achieved rates as high as 648 m (2,126 ft) per month in April 2018, and as much as 37.4 m (122.7 ft) in one day. The Crossover TBM did not encounter high-pressure water and was thus used in hard rock Double Shield mode throughout tunneling.
“The TBM performed very well, as did a Robbins-supplied adit conveyor that operated in a 180-degree continuous curve. It was impressive,” said Max Walker, Robbins Field Service Superintendent. Several field service personnel remained onsite throughout operation of the TBM to provide guidance and trouble-shooting.
The machine was launched in November 2016 following Onsite First Time Assembly (OFTA), which enabled the machine to be initially assembled at the jobsite. The crew ramped up production slowly over the next 230 m (755 ft). “Ground conditions were good and we did very few cutter changes—only 20 cutters were used during the bore,” said Walker. Two-stage grouting was carried out as the TBM bored and lined the tunnel in three 8-hour shifts. “The personnel on this project have created a friendly work environment; they’ve made it enjoyable coming to work each day. They’re good guys to work with,” he added.
While the TBM did not need to be sealed, the unique machine design took into account a predicted high risk of water inflows. The Crossover XRE machine used a belt conveyor and not a screw conveyor for muck removal, so the muck chute needed to be able to be sealed off in the case of an inrush of water. The bulkhead was thus designed with a large sealing gate just above the belt conveyor. These pressure-relieving gates could also be used in a semi-EPB mode: As the pressure built in the cutting chamber, the gate would then be opened by the pressure, and material would spill onto the belt. As the pressure lowered, the gates would then automatically close, again sealing off the chamber. In extreme cases, the gates could be sealed and the probe/grout drills could be used to drill, grout, and seal off water. Additionally, the gripper shoes and inner telescopic shield were designed with inflatable seals to further protect against inrushes of water.
With the breakthrough now complete, grouting will continue behind the TBM segments. No additional lining will be added, and the tunnel is expected to become operational by May 2019.
The 6.7 km (4.2 mi) long Moglicë headrace tunnel is part of the Devoll Hydropower Project, a Build-Own-Operate-Transfer (BOOT) scheme to construct two hydropower plants along the Devoll River, named Moglicë and Banja. The project is owned by the Norwegian power company Statkraft AS. The completed Devoll Hydropower Project will increase Albania’s electricity production by 17% and will have an installed capacity of 242 MW.
Image 1: A 6.2 m (20.3 ft) Robbins Crossover (XRE) TBM broke through at the Moglice Headrace Tunnel in Devoll, Albania on May 3, 2018.
Image 2: The breakthrough of the Robbins Crossover (XRE) TBM marks the completion of the first TBM-driven tunnel in Albania.
Image 3: The TBM bored a 6.7 km (4.2 mi) headrace tunnel for the Devoll Hydropower project, advancing at rates of up to 648 m (2,126 ft) per month.
Image 4: Robbins Field Service personnel assisted contractor Limak throughout the project with guidance and trouble-shooting.
Industry News, trenchless products
ECHO Utility Engineering and Surveying focuses on a specific aspect of Utility Engineering: Subsurface Utility Engineering.
Subsurface Utility Engineering (SUE) refers to a branch of engineering that involves managing certain risks associated with utility mapping at appropriate quality levels, utility coordination, utility relocation design and coordination, utility condition assessment, communication of utility data to concerned parties, utility relocation cost estimates, implementation of utility accommodation policies, and utility design.
ECHO purchased a Vac-Tron AIR 373 SDT vacuum excavator in 2017 and shared the benefits this unit has created for the company.
Project Descriptions
Locating existing subsurface utilities data.
Solution
Vac-Tron Low Profile AIR 373 SDT unit with customized accessories. This unit is powered by an 83 HP Yanmar diesel engine that delivers unmatched power and performance. Hand built in the USA from the ground up including the durable I-Beam trailer assembly. The low profile trailer keeps the components of the unit easily accessible while making the unit safe to tow and a much smoother ride. The AIR unit comes equipped with a hydraulic rear door, which opens fully so the operator can completely empty the contents. For operator safety, the door is controlled by push buttons located on the side of the unit. The AIR unit offers the patented filtration system with 0.5-micron filtration that is unmatched by competitors. It also comes standard with a reverse pressure system and a heavy-duty trailer with Dexter torsion axles.
Results
ECHO has been using the Vac-Tron AIR unit for over a year now. The main efficiency has been getting into tight places and safely onto curbs with the Low Profile unit. “It allows us to get to projects that we normally wouldn’t be able to do,” says President of ECHO UES, Jerry Comellas. “One of the projects we worked on was in a covered garage and if it wasn’t for this unit there is no way we could have accomplished the project because of the low clearances. This was a $48,000 project and is revenue that we wouldn’t have been able to have otherwise.”
“Vac-Tron’s customer service has been outstanding, getting us setup quickly, as our business works really fast, and catering to some of the refinements we made on the unit made it a pleasure to work with Vac-Tron,” Jerry concluded.
Check out the full video interview with ECHO and the unit in action here. For more information on Vac-Tron Equipment and its full fleet of vacuum excavators, please visit them online at www.vactron.com or call 1-352-728-2222.
Industry News, trenchless products
Over 500 water, wastewater and reuse pipeline installations completed
Overview
Texas municipalities have long been known for their use of trenchless installation methods. Engineers and contractors have been taking advantage of the social and economic benefits of trenchless installation for many years. Until 2004, the primary pipe material used for trenchless applications in water, sewer and water reuse projects was high-density polyethylene (HDPE). With the introduction of Fusible PVC® pipe, owners, design engineers and contractors now have the alternative of a thermally butt-fused PVC pipe system with all of the advantages and familiarity of AWWA C900/C905 PVC pipe. With PVC pipe already widely used in many utility systems, Fusible PVC® pipe allows utilities to maintain material continuity when constructing trenchless installations or direct bury applications requiring a fused thermoplastic pipe system.
A growing list of Texas municipalities and utilities have achieved significant savings by utilizing Fusible PVC® pipe systems while realizing the benefits of a leak-free, fully-restrained, fused PVC pipe system that is easy to maintain. Many municipalities that
have installed Fusible PVC® pipe have become repeat customers and have incorporated the technology into their standard specifications. Whether drilling in clay and sand along the Gulf Coast, or rock formations in North Texas, Fusible PVC® pipe has
demonstrated its ability to handle installation challenges.Over 500 water, wastewater and reuse pipeline installations completed Fusible PVC® pipe offers many advantages that lower overall project and maintenance costs, including:
- Inside diameter (ID) matches the ID of bell-and-spigot PVC pipe, so there is no need to upsize to maintain hydraulics
- Tensile strength of 7,000 psi is 2.5 times higher than the other thermoplastic pipe option
- Superior strength to weight ratio for equivalent ID and pressure class
- Hydrostatic design basis with 2.0 factor of safety
- Standard ductile iron pipe size outside diameter allows seamless connection compatibility with standard ductile iron fittings
Underground Solutions, Inc. provides infrastructure technologies for water, wastewater
and power cable conduit applications. Underground Solutions’ Fusible PVC® pipe
products, including Fusible C-900® pipe, Fusible C-905® pipe and FPVC® pipe, utilize
patented technology to produce a fused monolithic, fully-restrained, gasket-free, leakfree piping system ideal for trenchless (horizontal directional drilling, pipe bursting and sliplining) or conventional “open-cut” installations and are available in 4-inch to 36-inch diameters. The combination of standard fittings and lower weight with higher flow for a given pressure class versus other thermoplastic pipes ensures that Fusible PVC® pipe brings greater economy to most pipeline projects.
Photo: Single HDD pull of 5,545 LF of 18-inch Fusible C-905® pipe in Corpus Christi
Hard Rock Machine crosses Finish Line Nearly Five Months Ahead of Schedule 
The completion of the 24.3 km (15 mi) tunnel nearly five months ahead of schedule is a monumental achievement considering the difficult ground conditions encountered. Rock types ranged from tuff to granite, sandstone, and andesite with multiple fault zones—conditions requiring nearly continuous ground support. Rock strengths varied widely from 35 to 206 MPa UCS (5,100 to 30,000 psi). The contractor cited a number of factors that contributed to the swift advance rates: “It is the stable and reliable performance of the Robbins machine, and the professional technical skills of the service technicians. The Robbins crew coordination, reasonable working progress arrangements and the sophisticated technology all allowed the project to make the fast advance rate,” said Mr. Wu.
The Jilin Lot 3 tunnel is part of the Jilin Yinsong Water Supply Project, which at 736.3 km (457.5 mi) is China’s largest scale water diversion project to date. Once operational the water lines will divert the water from Fengman Reservoir at the upper reaches of Di’er Songhua River to central regions of Jilin Province experiencing chronic water shortages. These regions include the cities of Changchun and Siping, eight surrounding counties, and 26 villages and towns under their jurisdiction. The project will optimize water resource distribution, improve regional eco-systems, and ensure better food production and water safety for the people of Jilin Province.
