Sep 11, 2017
Custom Robbins Machine finishes on a High Note under Low Cover
The TBM, known an XRE—a Crossover (X) between Rock (R) and EPB (E) TBMs—navigated fault zones, variable ground, low cover, and more to achieve a national record of 57 m (187 ft) in one day as well as maximum rates of 231 m (758 ft) in one week and 702 m (2,303 ft) in one month.
“The XRE has a great advantage as it is designed to work in open and/or closed mode (EPB); allowing it to excavate the tunnel either in soil or in rock. We’ve verified that its performance was very efficient,” said Ing. Juan Alberto Herrera Moro y Castillo, TEP II Section Chief for owner CONAGUA, Mexico’s National Water Commission.
“The benefits of the design are in its exceptional thrust power and in the ease of changing the cutterhead torque. This makes the process much easier should the machine become stuck in difficult ground,” said Alberto Martinez, head of the tunneling department for RECSA.
The XRE machine was launched in August 2015 to bore the 5.8 km (3.6 mi) long wastewater tunnel. The machine was set up in a hard rock configuration and mounted with 20-inch diameter disc cutters. Early in 2016 the TBM hit the first of several contact zones, a 30 m (98.4 ft) wide fault of fractured and blocky rock. While the excavation through the contact zone was slow going, progress picked up again in the more competent andesite rock. After an intermediate breakthrough in March 2016 into an 80 m (262.5 ft) deep shaft followed by inspection and maintenance, the TBM continued on.
While boring in fractured andesite rock in autumn 2016, the TBM encountered a naturally occurring cavern believed to be the result of either a rock fall in a transition zone, or an old, underground lake body that had eroded the rock away. The cavern was estimated at 90 cubic meters (3,200 cubic ft) in size, including about 57 cubic meters (2,010 cubic ft) of unstable floor area. The TBM was stopped and immediate measures were taken to stabilize the ground in front of the machine with polyurethane foam before filling the cavern with a mixture of pea gravel and grout.
“We were able to do this without causing damage to property owned by neighbors in the zone bordering the path of TEP II, or to the road or the urban infrastructure installed in that area,” explained Ing. Francisco Miguel Lopez, Jobsite Manager TEP II for contractor Aldesa.
Now that tunneling is complete, the tunnel will receive a secondary concrete lining of 35 cm (14 in) thickness before going into service. The wastewater tunnel will overhaul the current system in western areas outside of Mexico City and serve to prevent recurrent flooding in Valle Dorado. In particular, the tunnel will benefit the cities of Cuautital Izcalli, Tlalnepantla, and Atizapan de Zaragoza, which altogether are home to 2.1 million inhabitants.
Mar 16, 2018
Mongolia is among those greatly struggling to keep their supplies of fresh water flowing. Since 2006, Fraunhofer researchers have been working hard to establish a sustainable water management system in the Mongolian city of Darkhan and the surrounding area. Their ...
Mar 15, 2018
Innovative satellite imagery technology helps cities efficiently locate underground leaks within aging piping systems stemming the loss of valuable drinking water.
Mar 14, 2018
ProStar was issued a key Canadian patent that covers a computer implemented method for calculating tolerance zones for utility assets. The patented method helps to prevent damages to utilities and the environment during construction, maintenance and groundbreaking activities as well ...
Mar 13, 2018
Jeffrey Kightlinger, general manager of the Metropolitan Water District of Southern California, issued the following statement following the state’s announced decision to stage the development of California WaterFix:
Mar 12, 2018
The consortium led by VINCI Construction, together with Spie batignolles, has been awarded a major contract as part of the Grand Paris Express programme. The RATP (1) has selected this consortium to execute works package GC02 of the future Line ...
Mar 09, 2018
Positions support HNTB’s growing number of tunnel and underground projects in the Western United States.
Mar 08, 2018
Challenging ground conditions are no match for talented team and their TBM.
Mar 07, 2018
American Water Works Company, Inc. is the largest publicly traded U.S. water and wastewater utility company.
Mar 06, 2018
Trenchless Pipe Bursting Manufacturer, TRIC Tools, introduces David Huff as its National Sales Manager.
Mar 05, 2018
Environment Minister Theresa Coffey has told British Water members that departure from the EU gives UK companies “new opportunities beyond Europe.”
Mar 02, 2018
Pipe Restoration Technologies, LLC, makers of the ePIPE, Lead-Free Leak-Free™ and LeadSmart® product lines, announced that it has been granted U.S. patents #9889469 and #9889470.
Mar 01, 2018
The first exhibitor announcements at the IFAT Media Dialog already showed: IFAT 2018 will cover all aspects of modern water and wastewater management. Expanded by two additional halls, which are fully occupied already, the World's Leading Trade Fair for Water, ...