Trenchless Technology

OCT 2018

Trenchless Technology is the premier communications vehicle for the trenchless industry. Through our multiple platforms, readers receive insights into the trenchless industry, as well as keep connected to the latest news, products and projects.

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Page 39 of 91

40 T R E N C H L E S S T EC H N O LO GY O C TO B E R 2018 it larger than average, previously repaired with a CIPP liner. The sewer line from the Drake to the main was a more typical 6-in. diameter pipe with a "tee" style connection to the mainline. Confronted with this unique challenge, LMK's technical team went to work, crafting a solution to repair the problem using a custom designed T-Liner. They decided that LMK's T-Liner would be the best solution to meet this need. The T-Liner system is a one-piece main- to -lateral CIPP connection liner. The liner is formed as a structural cylinder and renews 18 in. of the mainline at the main- to -lateral interface and extends up the lateral pipe simultaneously. The T-Liner can line a service lateral up to 150 ft from the main pipe in one installation. The system utilizes hydrophilic rubber gaskets, compliant with ASTM F3240, which swell after becoming moist , and form a seal between the host pipe and the new liner which therefore provides a watertight connection, eliminating groundwater inŽiltration and wastewater exŽiltration. Because of these unique features, the T-Liner is compliant with ASTM F2561, which is the industry standard countless sewer agencies turn to when looking to simultaneously rehabilitate a sewer service lateral and its connection to the main using a single liner. Trenchless installation of LMK Technologies' T-Liner system would structurally renew the leaking pipes quickly and without shutting down streets and businesses, and it was much more cost- effective than dig- ging . Most importantly, the Drake Hotel was able to stay open during the entire process. Dannenberg con- tacted Quam Construction , a Minne - apolis contractor and LMK licensed contractor, for this project based on a past record of success working to - gether on multiple projects since June 2015, when Quam Žirst entered the Žield of trenchless lateral rehabili- tation . "Our relationship with LMK has been fantastic," Quam vice president of trenchless pipe solutions Judd Stat- tine says. " Working with LMK has al - lowed us to diversify our labor, expand our tool box , and have more trench- less solutions in general ." Quam veri- Žied the pipe and its shape and size by accessing the manhole in the street , providing critical details LMK needed to design the T-Liner. LMK technical staff custom-designed and tested its trenchless solution, while the Quam team worked out the on- site details on how to complete the installation while keeping trafŽic moving and the Drake Hotel in operation. To lessen its impact , the project was split into two different phases, timed to be under- taken one week apart . The project Žirst required a sewer lateral cleanout outside the hotel . LMK's ASTM F3097 compliant trench- less VAC-A-TEE system was the chosen solution because it would enable in- stallation of a cleanout access point with minimal equipment footprint and minimal disruption to the sur- face. Phase 1 would be to site and install the VAC-A-TEE. Phase 2 would be to repair the lateral service con- nection utilizing the cleanout with a T-Liner, which would extend 8 ft up the service lateral pipe to be installed from the sewer main. Working closely with the City, Quam closed the street parking lane, creating one single lane of trafŽic, on the June evening chosen for the execu- tion of the Phase 1 cleanout installa- tion. After the cleanout was installed, they backŽilled the area with sand and a layer of black dirt to restore the clea- nout site to its original condition. The process, which took only three hours to complete, began at 9 p.m. With minimal disruption, Phase 1 was suc- cessfully concluded. Phase 2 began exactly one week lat- er. Again at 9 p.m ., Quam closed three lanes of the road and used the park- ing lane so trafŽic could Žlow between 10th and 9th streets, as well as 5th Avenue South . The crew used a spe - cialized single - access self-propelled robot to clean the pipe and con- nection , removing all obstructions. It then fully saturated the T-liner with resin , loaded it into the liner 's launching device, and pulled it 215 ft into the mainline pipe to the repair location . Using the VAC-A-TEE clea- nout installation , the crew watched the positioning of the liner during the inversion process in real time with a CCTV camera . Once the liner was positioned, air pressure was used to inŽlate the main- line portion against the sidewall of the 18-in. diameter oval mainline pipe and the lateral liner was then inverted up the service pipe, also us- ing air pressure. Once the liner was fully inverted, Quam used steam curing methods, which took 75 min- utes. Once cured, Quam removed the bladder and launcher assembly from the mainline pipe. After a CCTV in- spection, the crew cleaned up and re- moved its trafŽic control equipment , restoring full access to the roadway by midnight . The City used compacted stone to Žill the sink hole, Žinishing the repair with asphalt . Phase 2 also took only three hours, and the entire project cost $17,000, saving the Drake Hotel $28,000 — or just more than one third the cost vs. open-cut excavation. "Overall , it 's accurate to say that the City is happy with the results," says Katrina Kessler, director of sur- face water and sewers for the City of Minneapolis. " The minimally invasive solutions were ideal because the issue was in a very congested part of down- town Minneapolis where we strive to lessen trafŽic concerns and impacts to residents and the traveling public." If the crew had used open-cut methods, it would have closed all the impacted roads during the two to three days re- quired to complete the job. Dannenberg notes that " being able to do this with trenchless technology — as the city advised — turned out to be a fantastic decision for all parties." LMK founder and president Larry Kiest Jr. agrees. " We are pleased with the results and ecstatic that the Drake Hotel was able to use trenchless CIPP rehabilitation methods. There is no challenge too big or too small for what we do. At LMK, we welcome challenges that require us to build unique solutions,' he says. Cody Delmendo is communications director and Eric Sullivan is Northwest Regional Manager at LMK Technologies.

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