United We Stand

In the aftermath of the September 11 attack, allowing our terrorist enemies to destroy our economic foundations would afford them a victory of enormous proportion. I believe that our entrepreneurial spirit is a strong weapon. Here at Cambridge, our reaction is positive and unwavering.

Although raw material and operating costs have risen, I am committed to maintaining 2001 prices into next year. Also, rather than cut back on our corporate advertising budget, I have authorized a 25% increase over last year for advertising support in leading consumer magazines. In addition, the $10,000,000.00 expansion of our manufacturing capabilities — initiated over two years ago with the purchase of additional real estate — will move forward as planned. We continue to stand behind our products and our ideals.

My personal commitment extends to you, our valued distributors and contractor-customers. I extend to you a firm handshake. Together we can not only endure… but also prosper. Our collective efforts will give testimony that the human spirit is alive and well within the growing Cambridge network. — Charles H. Gamarekian (top)

Pave Tech’s SandLock Organic Joint Stabilizer Additive

An organic sand binder, which seals sand that is swept into the joints of interlocking concrete paver systems, SandLock offers an economical, non-toxic and non-staining alternative to chemical joint stabilizers. Easy to use, SandLock is designed to mix with the sand at the job site before compaction. Simply mix... sweep... then activate with water to create bonded yet flexible joints. And application of the product is done at the same time as compaction — in one easy step! Because the stabilized sand remains flexible, thermal movement is accommodated without cracking. Sand loss due to wind, traffic, moisture and thermal movement is reduced. SandLock also prevents weeds from wind blown germination and is highly effective against ants. Great for pool decks!

Since there is no need to wait for setup or curing, completed pavingstone systems are ready for traffic immediately. For more information, refer to 2002 Product Line Specifications.

Probst Pounder

A perfect multi-purpose tool! The Pounder comes with three bits — each designed for specific tasks. The Breaker Point is ideal for breaking up poured concrete and asphalt. Cleaning protrusions off edges on butted pavements and splitting retaining wall blocks can be easily accomplished with the 3" Chisel. For areas next to foundations, in tight corners and around exposed utilities, which are too restrictive for a motorized plate compactor, attach the 6" x 6" Tamper Plate. (top)

Adding Impact With A Circle Or Fan

Keep circles and/or fans in mind when exploring ideas for your next project. The following information may stimulate the creative process:

1. Cambridge Circle Design Kits are available from The RoundTable Collection, and now, The Renaissance Collection (see cover story). Each kit consists of six different shapes that, when installed according to easy-to-follow instructions, will form a circle. No cutting of the actual shapes in the kit is necessary. Refer to DesignScaping Installation Pattern DSR-001, which is available from your Cambridge Distributor or on our Web site (www.cambridgepavers.com).
2. Each kit will create a circle of 8.5' in diameter. To expand the diameter, a second kit is required. Fan designs can also be completed from one or more Circle Design Kits.
3. Kits from The RoundTable Collection are available in all standard Cambridge colors. Kits from The Renaissance Collection are available in Onyx/Natural, Toffee/Onyx and Sahara. Consider placing contrasting rings using different kits.
4. Be creative! Circles and fans can be incorporated into fields from all Cambridge Collections. Varying surfaces in Renaissance and ArmorTec can add even more impact. (top)

The Subgrade And Base: Two Critical Components

Typically, installation steps include job planning, layout, excavating and compacting the soil subgrade, applying geotextile (optional), spreading and compacting the base aggregates, constructing edge restraints, placing and screeding the C-33 washed concrete bedding sand (do not use stone dust), placing the pavers, compacting, filling the joints with C-33 washed concrete sand, and compacting again. Of these steps, proper preparation of the soil subgrade and base are essential to the long-term performance of interlocking concrete pavements.

Excavating And Compacting The Soil Subgrade

Unless the pavers are to be installed entirely over existing asphalt or poured concrete, the base is placed over a compacted soil subgrade.

It is important not to excavate beyond the desired depth that is required. Doing so would unnecessarily disturb soil below the actual subgrade and could compromise results. Organic materials, roots, debris and rocks found during and after excavation should be removed and replaced with clean, compacted backfill material. Free-standing water saturating the soil should also be removed. Soil should then be stabilized with a layer of crushed stone.

Compaction of the soil subgrade using a plate vibrator at 3,000-5,000 cycles is critical because it will minimize settlement. The objective should be 95% of standard Proctor density. This should be modified where constant vehicular traffic will occur. It may not be possible to achieve this standard in extremely saturated or very fine soils. Soil stabilization using geotextile fabric may be necessary. As a separation layer, it will prevent soil from being pressed into the aggregate base under loads, reducing the likelihood of rutting. Geotextile also helps over clay and moist silt, or where there is freeze/thaw. The fabric is placed directly on the excavated area with the sides turned up enough to cover the sides of the base layer to follow. Avoid wrinkles on the bottom.

Thickness of the subgrade is determined by traffic, soil type, drainage, moisture and climate. Over well-drained soils, pedestrian areas require 4" and residential driveways, for instance, need 8” after compaction. Add 2" - 4" where soil is weak or continually wet. Be aware that local or state engineering standards may apply.

Spreading And Compacting The Base Aggregates

Recommended base materials — quarry process or state-approved, recycled concrete — accommodate minor settlement as well as access to underground utilities. Sold by the ton, the crushed stone ranges in size from 3/4" to very small particles. The range creates a dense material that when compacted, will spread loads. The base is placed over the soil subgrade, under the bedding sand and pavers.

Using patios and walkways as an example, a minimum of a 4" - 6" base should be used. Driveways require a minimum of 8". For low lying or wet areas, thicker bases are in order. The base is installed in 4" lifts (layers). For drainage, slope away from buildings. To remove rainfall, walkways and driveways should also be sloped. A proper slope is achieved by grading the soil, not by decreasing the thickness of the base. Each lift must be compacted using a plate vibrator and special attention should be given to areas adjacent to edge restraints, catch basins and utility structures (see Probst Pounder, Products & Tools, in this issue). When spread and compacted, the base should contain optimum moisture. Spray (do not hose) additional water evenly over the spread base if necessary. Compact pedestrian and residential driveways at a minimum of 95% of standard Proctor density. While !00% is preferred for vehicular areas, compaction should be at least 95% of modified Proctor density as determined by AASHTO*. The finished base surface should be thoroughly inspected for any areas that might allow bedding sand to migrate into it.

Following these simple instructions will not only decrease the likelihood of settlement and call backs, but will produce long lasting results. For more details, refer to Tech Spec Number 2, available from Interlocking Concrete Pavement Institute (ICPI) or your authorized Cambridge Distributor.

*American Association of Highway & Transportation Officials (top)

Segmental Paving: Then And Now

The invention of the wheel made it necessary for pavements to withstand concentrated loads. Almost every civilization — the Romans, Mayans, Babylonians, Persians, Chinese, Aztecs and Egyptians — discovered that tightly fitted stone over an aggregate base was the best solution. Looking back, the year 2000 marked 5,000 years of humanity using segmental paving for roads, sidewalks and public plazas as well as residential areas.

Over the past 25 years, interlocking concrete pavements eclipsed other forms of segmental pavements. 1975 to 1985 saw a huge growth to over 50 paver plants in North America. Currently, over 300 million square feet of pavers have been installed and over 80 facilities operate in this part of the world alone.

The introduction of mechanical installation along with the introduction of specialized hand tools in the mid-1980s accelerated installation rates, allowing contractors to gain high efficiency on larger projects without sacrificing quality. New architectural finishes such as tumbled (an example: Cambridge Renaissance) and face mixes (an example: Cambridge ArmorTec), were also being introduced. Concrete pavers positively addressed recurring issues such as environmentally-sound ("green") construction, managing maintenance and life-cycle costs and also aesthetic appeal (the "feel good" philosophy). As a result, engineered paver systems became more attractive to markets other than residential, such as urban renewal, developers, airports, seaports, etc. However, 70% of uses remain residential.

Photo Caption: Cambridge 3 1/8" thick Holland Pavingstones in Ruby/Onyx, placed in a herringbone pattern, were specified for this Atlantic City urban renewal project.
Cambridge Distributor: Clayton Block.
Contractor: Medio Construction.

DID YOU KNOW...?
Paver installation contractors were recently recognized by the U.S. Department of Labor as a distinct construction trade? Yet with all this, the industry is still in its infancy. For example, according to a 1995 study, all segmental pavement represented only 2% of the new residential driveway market. This new century promises full integration of concrete segmental paving into our visual landscape... making business opportunity more vibrant than ever. Seize the moment! (top)

Inside Tips On Outside Displays

Outdoor displays of Cambridge Pavingstones can offer your customers a close up view of segmental pavingstone systems. Many distributors also report that a well-planned display can reduce actual selling time because customers often make decisions based on what they like in a display. Therefore, put displays in a prominent place where customers can walk on them.

There exists a misguided perception that there isn't sufficient room for a display. Why not install a sidewalk of various patterns, shapes and colors? By separating each example with a common border course, an aesthetically pleasing and cohesive effect will result. A smaller size shape (i.e. 3 X 6 or 4 1/2 X 6) in between patterns will lessen the overall space required. Walk-on displays can work inside too!

Above all, use imagination. Mix Cambridge Collections and surfaces to stimulate ideas. Placing certain shapes, such as our Tulip paver, on a 45° angle will look better. Consider patterns that are "contractor-friendly". Certain patterns translate into higher installation fees for your contractor-customer. Remember, add-ons like Paver Lights will boost a sale! When incorporating a Cambridge Wall System into your design, make it a contrasting shade.

Ask your Cambridge Sales Specialist for assistance… he'll know what displays have proven to be effective. (top)

Elevated Patio With Paver Overlay Looks Over Pool Deck

Architecturally speaking, this tiered balcony/patio on piers with its sweeping circular design makes quite a statement in and of itself. But considering that the raised areas provide an overview of the pool deck below, the effect is even more breathtaking. The pavers on the elevated areas are an overlay on a raised concrete deck.

CONTRACTOR:
Davis Horticultural, Milford, PA
Cambridge Distributor: Daron Northeast,
Ashley, PA

INSTALLATION DETAILS:

1. Raised Patio — Concrete Base,
   Geotextile & C-33 Washed Concrete Sand
2. Pool Deck — Quarry Process, C-33
   Washed Concrete Sand & Pavers

Cambridge Pavingstones: In Chestnut —
6 X 6 and 6 X 9 from The RoundTable Collection & Bullnose from The Crusader Collection(top)