11.08.2022

Update on Sika's MBCC Acquisition – Closing targeted for H1 2023

The UK Competition and Markets Authority (CMA) has decided to conduct an in-depth examination in the UK market related to Sika’s planned acquisition of MBCC Group.  

10.08.2022

LOESCHE Sustainability Report 2021

LOESCHE published its first sustainability report in July 2022. The report refers to the calendar year 2021.  

09.08.2022

First cargo Vessel calls at the Fehmarnbelt Project’s Work Harbour

The first vessel carrying materials for the construction of the Fehmarnbelt has docked. First cargo vessel calls at the Fehmarnbelt project’s work harbour.  

08.08.2022

BHP announces non-binding indicative Proposal to acquire Oz Minerals Limited

BHP has submitted a non-binding indicative proposal to the Board of OZL on 5 August 2022 to acquire 100% of the issued share capital in OZL by way of a scheme of arrangement (the Proposal).  

Market-Place-4.0 Robbins Company

06.08.2022

Landmark Breakthrough for Robbins TBM ‘Big Tex’

A crowd gathers as the Robbins TBM breaks through into a shaft at the Mill Creek Drainage Relief Tunnel in Dallas, Texas, USA. (credits: Robbins)

Main beam holes through to fanfare after changing diameters

On July 25, 2022, a crowd gathered as a large Robbins Main Beam TBM, dubbed ‘Big Tex’, broke through in Dallas, Texas, USA. The machine and its continuous conveyor system, for the Mill Creek Drainage Relief Tunnel, successfully bored 8 km (5 mi) in chalk and shale at up to 498 m (1,634 ft) advance in one month. “I think when you step back and look at what was accomplished by this team as whole … the overall length and size of this tunnel, the TBM conversion, the everyday grind to keep moving forward … it truly is something to be proud of, professionally and personally. No single individual could reach this milestone. It took a great team of skilled individuals. I am fortunate to be a part of it,” said Nick Jencopale, Sr. Project Manager for contractor JV Southland/Mole.

Good advance rates were not the only cause for celebration: the unique project required a planned in-tunnel diameter change of the TBM from its original 11.6 m (38 ft) to a more compact 9.9 m (32.5 ft). The first-of-its-kind conversion process was undertaken 2.8 km (1.7 mi) into the bore and was not done inside a shaft or pre-excavated portal. “The TBM conversion was a unique challenge that we were excited about, and ultimately provided a more efficient method for the desired product compared to the alternative options. Hopefully the successful conversion proved that this option can be considered for future tunnel projects,” said Jencopale.

While there were many detailed steps to the conversion process, precision design of the machine was a key aspect.  “We started with a smaller machine, then we made a kit or second skin that was slightly larger. And then when the time came, we just took that skin off. It was essentially that simple,” said Evan Brinkerhoff, Robbins Field Service Manager. The conversion took about four months and was completed in April 2021.

“The Robbins Main Beam TBM (‘Big Tex’) performed consistently throughout the duration of the tunnel excavation. There were very minor issues and little overall downtime as a result of the TBM itself,” said Jencopale. Due to the relatively favorable ground conditions in much of the tunnel, including low rock strength and low abrasivity, only eight disc cutters were changed during the length of tunnel bored at the larger diameter. At the time of diameter change the full dress of cutters was changed, and since that change only 14 cutters have needed replacing. Crews did encounter some fault zones, and installed rock bolts and wire mesh in the tunnel crown as needed.

With the TBM-driven portion of the tunnel now complete, work can commence to remove the machine from the tunnel and install a final lining. The tunnel is a designated critical infrastructure project for the City of Dallas, providing 100-year flood protection for areas of East Dallas that have experienced severe flooding in the past. Construction work is expected to be complete in late 2024/early 2025.

Source: Robbins

#breakthrough #flood protection #United States (US) #Robbins Company #Tunnelling #hydraulic engineering #Conveyor technology #tunnel boring machines (TBM)