Tuesday, December 28, 2010

Controlled Low Strength Material (CLSM)


CLSM is a very versatile "liquid soil" which is placed as a flowable liquid, yet hardens and rapidly develops exceleent load bearing properties, without requiring compaction.

Flowable, cementitious fill was initially developed in the early 1970's as a replacement for poorly compacted soil. Over the past several years, CLSM has been used in lieu of compacted soil and granular fill for end-uses including bedding and backfill for utility trenches, paving subbase, bridge abutment and retaining wall backfill, along with, tunnel, sewers and other underground structures, and tight access areas. CLSM is typically comprised of combinations of cement, water, fine aggregate, fly ash, possibly coarse aggregate and more recently, chemical admixtures. The material properties of CLSM encompass both concrete and soils. They usually fall well below low-strength concrete, but are superior to most high quality compacted soil fills. CLSM is batched and mixed in central-mixed concrete plants or ready-mix trucks, transported via ready-mix trucks, and placed by chutes, conveyors, buckets, and pumps.

"Speeds construction, Reduces labor and equipment, and does not settle."

Sunday, December 19, 2010

Tapping With COSMO Work Under Pressure and COSMO Inserting

Hi all friend, Today I have knoeledge for all >>>>
Some time during in tapping process. I hope water supply continues duringwork is done without shutting water supply. No need of water supply stop notice. water supply car preparation, red water treatment. No need of inner pipe cleaning after work. Manpower and goods for work are saved.

"Work under pressure" Hot tapping, Wet tapping, Pressure tapping Cosmo developed an epoch-marking technology in 1959. That 's a technique that a branch can be done without shutting water supply of main using a divided tee and a special boring machine. this technique makes most branching works for water works done without shutting water supply today.

"Meahanism of Process with Cosmo"
1. Assemble a Cosmo valve and boring machine on the main pipe.


2. Bore the pipe by feeding the cutter of the boring machine with rotating it. Chips are drained off.


3. Feed back the cutter on full stroke and shut the valve.


4. Remove the boring machine, connect a new branch and open the valve.


More information contact with under link. Bye :) :)
cosmo-koki

Line Stopping Procedure

Bypassing large diameter sewers for repair, replacement, or rehabilitation. Line stopping involves using special equipment and techniques to stop the flow in the pipe and bypass it around tha damaged section so that replacement can be made.

The process goes like this:
step 1: First, a saddle and tapping valve is placed on the old pipe and the hot tapping (Cutting) machine is mounted on top of the tapping valve.

step 2: The tapping valve is opened, and the cutter is advanced through the top of the pipe. The housing of the hot tapping machine contains

step 3: Then, the cutter is retracted back into its housing, the cutter and hot tap machine are removed, and the linestopping machine is placed on top of the tapping valve.

step 4: The bypass pipe is attached to the linestopping machine, the tapping valve is opened, and the flow fills the bypass pipe.

step 5: The plugging head is dropped into position, stopping the flow and isolating the downstream section of old pipe.


When the permanent bypass is complete, the plugging head is retracted, the tapping valve is closed, and the linestopping machine is removed.

Thank you for good information from
Paul Wilting, P. Eng.
Senior Project Engineering
Greater Vancouver Regional District.
& Allan Herle, P. Eng.

Presented at:
No Dig 1999 Conference
North America Society for Trenchless Technology
orlando Florida May 23-26, 1999

Wednesday, January 13, 2010

Polyurea For Finest Surface Protection


This is the best for Waterproofing, Epoxy Flooring, Corrcion Protection, Fact repair compounds, Heat Reflective Coating and more...

"Polyurea" is derived from the reaction product of at polyisocyanate component and an amine-terminated vesin bleand. Compound with two part system there.

- One partis Isocyanate component "reactive isocyanate groups (-NCO)".
- One port is a Resin blend component "reactive group is amine (primary or secondary) (-NH2 or - NH-).
- Reaction of the two components yields aurea linkage.

!!! Polyurea is not a Poly urethane
!!! Polyurea does not contain a catalyst
!!! Poly urea improves moisture resistance
!!! Polyurea cure not affected by temperature or humidity

Characteristics

- Fast, consistent reactivity / no catalysts
- Relative environmental processing insensitivity
- Excellent mechanicsl properties
- Good adhesion to a variety of substrates
- 100% solids formulations

Advantage

- Single coat application
- Suitable for steel and concrete decks
- USDA & FSIS approved
- Potable water ANSI/NSF61 approved
- Flame Retardant
- In-service resistant to to cold and heat -40C to +230C
- Flexible
- Greater than 150๔ elongation
- Long life expectancy
- Will not hydrolyze or biodegrade

Long Life Expectancy

- After exposure to a total of 3800 hours, using UVB-313 bulbs at 50 C, the physical property retention was at least 80%
- Unlike crystalline nature of polyurethane and epoxy, BDM is amorphous in nature. It has 2 distinct Tg's or Glass Transition Temperature., with a low temperature noted at about -50 C to 260 C. This would be the performance range, temperature wise.
- BDM is saltwater resistant. A major construction project in Boston under the direction of Bechtel, Parsons & Brinkerhoff specified our system on the exterior of a concrete tunnel of an immersed tube/tunnel.
- When exposed to an elevated temperature of 80 C, this nominal temperature has little to no effect on the polymer.
- Based on testing, flexibility of the system, chemical resistance and thermal properties, our polymer is expeced to survive a minmum 75 years in saltwater application area.

More Information Contract
Unitcoat Asia Compary Limited
www.Unicoat.com/