New Advances in Repair and Strengthening of Piles

Submerged piles often corrode with age and shed their original load-carrying potential. When alternative is not an solution, these piles have been ordinarily fixed by encasing them in a fiberglass shell that is stuffed with concrete. These sorts have to have highly developed ordering, are cumbersome to ship and retail outlet, and give minor structural benefit. Right after additional than 3 a long time of advancement and many U.S. Patents, the PileMedic® process can be an choice to classic approaches.

Primary Rewards
As opposed to typical laminates that are four toes broad and are supplied in 100-foot-extensive rolls, PileMedic® is a new variety of Fiber Bolstered Polymer (FRP). A single pallet of PileMedic® consists of 1,000s of sq. feet of laminate, plenty of to repair service more than 50 piles. The major advantages of the laminate compared to common fiberglass sorts contain:

Power – PileMedic® laminates are up to two to 3 periods more powerful than metal.

Sizing & Condition – The .05-inch-thick laminates are adaptable more than enough to be wrapped all-around piles of any form and dimension.  In the field, a size equivalent to 2 times the perimeter of the pile is cut from the lengthy rolls. The second 50 percent of the laminate is coated with a unique epoxy paste, and it is wrapped all around the pile onto the first layer to generate a two-ply structural shell around the pile. This removes the need for personalized buying the jackets, preserving important time, and transport and storage charges. The annular area amongst the jacket and the pile is loaded with grout, concrete, or epoxy grout later.

Confinement – The one of a kind seamless jackets utilize a uniform confining stress 360 levels about the pile. This raises the energy of the timber or concrete pile drastically and is a advantage that are unable to be obtained with typical fiberglass forms. Numerous strengthening jobs get in touch with for placement of longitudinal bars and ties all over the pile. These rebar cages are cumbersome and will have to be handled by two or additional divers. PileMedic® jackets also remove the want for lateral ties, enabling the divers to install the vertical reinforcing bars individually (when required). The elimination of dealing with assembled reinforcing cages that calls for two divers, success in significant value personal savings for the task.

Corrosion Protection – It is properly identified that the oxygen present in h2o is the fuel for the corrosion course of action. The laminates make a seamless and impervious shell close to the pile, protecting against any humidity or oxygen ingress. This will substantially decrease the corrosion rate in the pile.

Enhancements to Building
The U.S. Navy is amongst numerous purchasers who have used the repair process. Various components have been produced that increase the good quality of design and final result in more precise engineering style and design:

Spacers – These plastic elements are available in numerous designs and measurements and provide a number of applications. Divers can go a zip tie as a result of various spacers and fasten them around the pile. The longitudinal reinforcing bars (ordinarily manufactured of non-corroding glass FRP) can be snapped into position. This enables the engineer to know the specific place of every bar to estimate the energy of the retrofitted pile. The spacers also determine the annular house concerning the jacket and the pile that will be crammed with grout or concrete. In some instances, the mend portion of the pile extends into the mud line and the soil supplies a seal at the bottom of the jacket for placement of the grout. Having said that, there are quite a few purposes where the duration of the maintenance is minimal to the splash zone, requiring the development of a seal at a level alongside the height of the pile wherever the jacket terminates. The skirt pin makes it possible for the development of that seal.

Shear Transfer in Metal Piles – The relative sleek surface area of metal piles inhibits bonding of any concrete encasement to the host pile. The patented ShearWrap® and ShearClamp® conquer this shortcoming and get rid of the have to have for any welding on the jobsite. Engineering calculations establish the dimensions and variety of these factors necessary for each job.

Profitable Exam Final results
The PileMedic® program has been analyzed by many authorities organizations. Caltrans done checks of concrete bridge pilings, which were seriously ruined in an earthquake. Texas DOT done a examine of corroded steel H-piles at the University of Houston. Even sections with up to 80{64d42ef84185fe650eef13e078a399812999bbd8b8ee84343ab535e62a252847} part decline attained their whole toughness immediately after being repaired with the technique. The Nebraska Section of Streets has also examined the repair of timber piles employed in the point out.

Extra a short while ago, the U.S. Army Corps of Engineers (ACE) done a main investigation of answers for exigent fix of piles. Centered on total-scale exams, ACE chosen PileMedic® for the U.S. armed forces to repair service timber, concrete, and steel piles throughout the world. As a section of this analysis, 90 concrete piles were fixed at Pearl Harbor in Hawaii. The installations also deemed a variety of circumstances this kind of as inadequate visibility in the water and drinking water present-day.  As mentioned by some of the diving group users, the new process decreases the restore time to as very little as 1/3 of the formerly utilised pile jackets. Taking into consideration that the labor/diving fees account for about 75{64d42ef84185fe650eef13e078a399812999bbd8b8ee84343ab535e62a252847} of the complete repair service expenditures, PileMedic® could end result in substantial time and cost savings in pile fix initiatives.

Discipline Installation
PileMedic® has been installed in a lot of assignments all over the world. Amongst these include in excess of 500 timber piles at Perdue Agrobusiness in Chesapeake, Virgina, wherever some piles experienced 100{64d42ef84185fe650eef13e078a399812999bbd8b8ee84343ab535e62a252847} area decline. Ninety concrete piles have been applied for the Port of Seattle. Houston set up 95 steel piles, Indiana DoT utilized 265 steel piles, and 100 piles had been utilized in a jetty belonging to the Nigerian Nationwide Petroleum Corporation. In addition, piles have been made use of at many bridges in Australia, a pier in Vietnam destroyed in a mooring accident, and by the U.S. Navy in the fix of a pier in Ukraine.

Mo Ehsani, PhD, PE, SE, is president of QuakeWrap Inc. and centennial emeritus professor of Civil Engineering at The University of Arizona. He can be reached at [email protected]. Complete aspects of the system are available in two recent webinars that have been recorded and can be obtain at www.PileMedic.com/webinars.html