FAST TRACK Selective Hydro-Demolition is a process to repair and prepare the total area of deteriorated bridge decks utilizing hydro-demolition equipment that is calibrated to selectively remove unsound concrete from the structural bridge deck slab and to provide a highly rough and bondable surface in the same pass of the hydro-demolition robot. It is an owner’s preferred method of preparing a bridge deck for a new Latex Modified Concrete (LMC) Overlay.

• During calibration of the hydro-demolition equipment, the settings of the hydro-demolition robot are determined so that “selectivity” is achieved. Selectivity is defined as removal of unsound and deteriorated concrete from the structural concrete deck slab with one pass of the equipment. Deeper partial depth areas and even full depth areas which could require additional repairs are also identified during this single pass. Removal of the sound concrete remaining in the deck slab is avoided when the proper “selectivity” settings are achieved.
• Selectivity occurs between 13,000 PSI & 20,000 PSI, when you calibrate hydro-demolition equipment. Anything below or above 13,000 PSI – 20,000 PSI will result in not removing or identifying all unsound concrete. See Standard Specifications.
• For speed of completion the top surface of the bridge deck is rotomilled first exposing cracks and pores in the concrete which allows FAST TRACK Selective Hydro-demolition to become extremely fast and efficient.
• Then the FAST TRACK Selective Hydro-Demolition equipment is calibrated not to remove a specific depth, but to selectively remove unsound concrete and to provide a highly rough and bondable surface for a new LMC Overlay to adhere to for a long term (25-30 years) maintenance free bridge deck surface for the owner and taxpayers.
• Water usage has no function in selectivity. From 20 GPM to 75 GPM, water flow rates are merely a function of speed. The more water you use, the faster the completion time is and time is money to owners and contractors.
• A 4,000 SYS bridge deck can be completed and opened to traffic in one week, which normally takes 6-8 months using conventional impact tools and labor. Total surface FAST TRACK Selective Hydro-Demolition and Very Early Strength Latex Modified Concrete (VESLMC) will perform for 25-30 years of maintenance free service life for an owner under a proper calibration where selectivity is maintained during the hydro-demolition process.

FAST TRACK Selective Hydro-Demolition Total Surface is a process to repair and prepare the total area of deteriorated bridge decks utilizing hydro-demolition equipment that is calibrated to selectively remove unsound concrete from the structural bridge deck slab and to provide a highly rough and bondable surface in the same pass of the hydro-demolition robot. It is an owner’s preferred method of preparing a bridge deck for a new Latex Modified Concrete (LMC) Overlay.

• During calibration of the hydro-demolition equipment, the settings of the hydro-demolition robot are determined so that “selectivity” is achieved. Selectivity is defined as removal of unsound and deteriorated concrete from the structural concrete deck slab with one pass of the equipment. Deeper partial depth areas and even full depth areas which could require additional repairs are also identified during this single pass. Removal of the sound concrete remaining in the deck slab is avoided when the proper “selectivity” settings are achieved.
• Selectivity occurs between 13,000 PSI & 20,000 PSI, when you calibrate hydro-demolition equipment. Anything below or above 13,000 PSI – 20,000 PSI will result in not removing or identifying all unsound concrete. See Standard Specifications.
• For speed of completion the top surface of the bridge deck is rotomilled first exposing cracks and pores in the concrete which allows FAST TRACK Hydro-demolition to become extremely fast and efficient.
• Then the FAST TRACK Selective Hydro-Demolition equipment is calibrated not to remove a specific depth, but to selectively remove unsound concrete and to provide a highly rough and bondable surface for a new LMC Overlay to adhere to for a long term (25-30 years) maintenance free bridge deck surface for the owner and taxpayers.
• Water usage has no function in selectivity. From 20 GPM to 75 GPM, water flow rates are merely a function of speed. The more water you use, the faster the completion time is and time is money to owners and contractors.
• A 4,000 SYS bridge deck can be completed and opened to traffic in one week, which normally takes 6-8 months using conventional impact tools and labor. Total surface FAST TRACK Selective Hydro-Demolition and Very Early Strength Latex Modified Concrete (VESLMC) will perform for 25-30 years of maintenance free service life for an owner under a proper calibration where selectivity is maintained during the hydro-demolition process.

Owner Benefits

The major #1 risk to an owner when putting out a bid for a bridge deck preservation or rehabilitation project are variable quantities.
Variable quantities cause all sorts of problems such as:

• Uncontrollable costs
• Extended time of completion
• More money required to complete
• Change orders
• Litigation
• Contractors not bidding apples to apples
• Unbalancing of bids, etc.

Basically performing work totally out of control in terms of problems and money.

The benefit to owner or consultants using FAST TRACK Selective Hydro-Demolition Total Surface and Latex Modified Concrete (LMC) Overlays is the ability to eliminate or reduce variable quantities. See the Standard Specifications section that has been developed by owners that fix cost for removal and replacement materials and pay “material cost only” for additional needed variable depth replacement. Owners can lock in their cost and perform more bridge preservation projects for money spent.

These General specifications have been developed by owners, such as Dennis Kuchler, a retired Chief State Construction Engineer for INDOT, and have saved owners millions of dollars. They have been developed exclusively for FAST TRACK Selective Hydro-Demolition and LMC Overlays and deviating from them brings the high risk variable quantities back into play.

For more information, please call Edward Liberati, PE at 502.693.3253 or emailing him at eliberati@hughesgrp.com.

Other Owner Benefits of using the Standard Specifications for FAST TRACK Selective Hydro-Demolition to prepare bridge decks and Latex Modified Concrete are:

1. Extreme control of cost.
2. High quality – long term structure relief.
3. No dust.
4. Extremely fast completion time – time is money.
5. No vibration.
6. No bond interface damage.
7. No micro cracking.
8. Removes unsound concrete or identifies where more work is required.
9. Highly rough and bondable surface for placement of latex modified concrete overlay.
10. No change orders.
11. No litigation.
12. Contractors bid on same fix cost items that ensures best possible cost to owners.
13. No variable quantities.
14. No impact tools that create further damage to bridge, additional costs and no interface bond damage
15. Chain dragging is not required by owner or contractor to locate unsound concrete.
16. Owner and contractor are not required to measure variable areas.
17. Reduction in job administrative costs for owner and contractor. Hydro-demolition unit replaces 60 laborers on jackhammers. The labor is gone!
18. Reduction in certified payroll.
19. Reduction in worker’s compensation claims.
20. Improvement in safety.
21. Savings for local businesses due to fast completion.

With jackhammers, labor and variable quantities, the owner receives the exact opposite of the 21 listed benefits above.

The removals are totally out of control with the use of jackhammers.

Latex Modified Concrete (LMC) was specifically designed by Dow Chemical Company over 45 years ago as a concrete bridge deck overlay material to withstand the harsh thin bonded overlay environment. LMC Overlays have been used to preserve bridge decks by many owners through these years resulting in long term maintenance free life cycles. Many LMC Overlays are still in service after 35 years.

The longevity of bridge deck LMC Overlays is directly related to locating and removing all unsound concrete from the structural bridge deck slab and placing the LMC on a very clean & bondable water saturated surface and performing the curing properly.

NOTE: When using rapid set latex (VESLMC) get approval from latex manufacturer in regards to the type and brand of cement used to make sure the cement used is compatible with the manufacturer’s latex.

There are 3 types of LMC, which are:

1. Type I: four day cure

2. Type III: 2 day cure.

3. Rapid set latex (VESLMC), which takes 3 hours to cure before you can open to traffic.

LMC Overlays and FAST TRACK Selective Hydro-Demolition Surface Preparation

is the owner’s choice for fast, high quality, long term bridge deck repairs and have passed the test of time.

Like FAST TRACK Selective Hydro-Demolition, LMC material and placement has a proven standard specification and methods of payment that will fix cost the initial 1¾ inch placement including LMC material and pay material cost only for variable depth areas and grade elevation corrections. Material cost is the cost of the latex provided by a latex concrete material supplier.

The Standard Specification on this site for LMC eliminates all variable risk and expensive overruns for an owner or consulting firm.

When placed on a highly rough and bondable surface, which FAST TRACK Selective Hydro-Demolition provides, and placed correctly, LMC will give an owner a 25 -30 years of maintenance free structural relief.

After certified approved materials are provided at the job site and the latex mobiles are calibrated and approved to install the thin bonded LMC Overlay properly, the sequence is:

1. Perform surface preparation of the concrete surface with 7,500 PSI water blasting after the FAST TRACK Selective Hydro-Demolition to clean the surface of foreign materials.
2. Wet the surface until it stops drying out. The wetting period in most specifications is not correct for the heat of the summer which might require 4-6 hours to wet and cool the surface before the surface remains wet.
3. After the surface is completely wet and not drying out, cover with clear visqueen plastic during mild spring and fall months. Cover with white visqueen plastic during hot summer months.
4. Back the loaded, calibrated latex concrete mobiles on the visqueen, down the deck to the finish machine.
5. Test each latex concrete mobile for slump, air content and yield before you start pouring. Take one quart latex sample from each concrete mobile mixer and make test cylinders to measure comprehensive strength.
6. Pour and finish latex concrete with an approved finish machine such as Bidwell or Gomaco. Do not use manual finish screed to finish latex.
7. Two days before the pour put burlap in water troughs to soak in water until completely wet. Place wet burlap on latex concrete that has been poured and cover with white visqueen plastic. Stay within 30 feet of the back of the finish machine with the curing process. Use no other material besides wet burlap unless approved by the latex manufacturer.

NOTE: When using rapid set latex (VESLMC) get approval from latex manufacturer in regards to the type and brand of cement used to make sure the cement used is compatible with the manufacturer’s latex.