Monthly Archives: August 2014

Aug 05

Architectural & Decorative Concrete

Posted on by

The concrete industry has come a long way and keeps reinventing itself to answer the needs of builders, architects and even decorators. With more and more home owners attracted to a greener and more sustainable lifestyle, we have seen, in more recent years, a new use of concrete, blending innovation and artistry to create truly unique surfaces for interior floors, patios and kitchen counters. Here are some of the coolest new possibilities:

Concrete Countertops in the kitchen:

Granite Counter top

When you think kitchen countertop, a few options usually come up. Depending on your budget, you can get high end and more expensive products like: polished granite, marble, quartz, soapstone, stainless steel and glass.  On the cheaper end and ideal for DIY afficionados, you have tile, wood and laminate. Other options that are becoming more popular are concrete and recycled concrete. The later one being one of the most eco-friendly choice that allows you to combine post-consumer products like glass, paper, composite and plastic with concrete for a truly unique finished product.

Plain concrete can be used in countertops, landscaping and customized with various textures and finishes (stain color). A really nice feature of concrete is its ability to be energy efficient. Whenever the temperature rises, the concrete traps the heat and releases it when the temperature cools down.

White Portland cement
 To transform what may be viewed as boring cold grey concrete into bright, elegant aesthetic surfaces requires a combination of special ingredients, forms and finishing technique. The magical ingredient in this case is white Portland cement.  It comes plain or pigmented and is available in wide array of colors, from pastel to saturated colors. It can be used indoor or outdoor and has the same durability properties as grey cement but contains more metal oxides like iron and manganese, giving it its whiteness. White cement concrete is used in exposed architectural concrete, landscaping, building accents and more. It provides greater energy efficiency and safety because of its light color.

Some design ideas

Stone finishing

Concrete can be transformed to look like natural stone. To create this effect, you will need to cast the concrete in an integral color then apply multiple layers of acid stain to the surface until the desired result is obtained. TIP: Use the veins produced by the marbelizing effect to hide seams on your countertop.

Wood grained concrete texture

 

Create a wood-grained finish to any surface by applying a technique called “board forming”. To create this unique texture, you will need to cast the concrete in forms that have been previously lined with unfinished wood that will imprint the wood texture into the concrete surface. You can also create board lines by cutting straight lines with a saw after it is cast. Next is creating a realistic color using both integral color with topical stains.

To create a smooth and elegant look to your surface, you can polish or sand your concrete. It is recommended that the counter top be poured in one piece and not show any seam. To create the look of marble, you will need to use a titanium-white concrete mix that contains white silica sand. You can also hand sand the surface lightly for a less shiny and more natural look.

Exposed Aggregate Finish
This is where the use of post-consumer products like glass, stones, bricks, even shells can be recycled and added to concrete to make truly unique finished surface. There are 3-4 steps to create this type of finish: first you pour the concrete, then you insert pieces of material of your choice (broken glass, decorative stone, shells etc.) Once the concrete has set  you grind the surface to expose the aggregate. Finish with a high gloss sealer to protect your newly created surface.
TIP: for spectacular results it is best to select pieces that will create the most contrast with the concrete color.

If you are looking for a good deal on a concrete pump or want to make sure you have the right pump for the job, give us a call at: (503)283-2105 or visit us at: Unitedequipmentsales.com

Related reading
 Milestones in the history of concrete construction
 Photos of concrete counter tops
Applications for architectural concrete

Share
Aug 02

How to Minimize Dust Exposure in Shotcrete Placement

Posted on by

Dust generation may seem to be part and parcel of any construction job and nothing to worry about but long-time exposure and inhalation of dust can lead to damaging health effects especially when working in tunnels and mining jobs.

Let’s first look into factors that cause excess dust and how we can avoid or reduce them. Take for instance, the process of building tunnels. It requires going through a series of steps that generate huge amounts of dust: drilling, namely: blasting, crushing, extracting and shotcrete. While the first four processes have to control the dust generated and remove it from the atmosphere through special ventilation, water sprays and dust collectors, shotcrete placement doesn’t.  However, hiring a shotcrete crew that is experienced in working underground will minimize dust generation because they will know how to control it at the source.

Silica

Where is silica found:
Silica is found in asphalt, brick, cement, concrete, drywall, grout, mortar, stone, sand, and tile. OSHA regulation 29 CFR 1926.55(a) requires that exposures must be below a Permissible Exposure Level (PEL) of 0.1 mg/m3. The National Institute for Occupational Safety and Health has a lower Recommended Exposure Level of 0.05 mg/m3.

Health risks from exposure to Silica:
Repeated exposure to cement dust will lead to irritation to eye, nose, throat and upper respiratory system. When skin is directly exposed to cement, further irritation can occur and skin cracking can result from chemical burns. Rinse eyes or skin with water and soap if it comes into contact with cement dust and if the burning continues consult a doctor.

Another serious risk for workers is lung injuries from Silica exposure. This can lead to chronic obstructive pulmonary disease (COPD), lung cancer, tuberculosis and Silicosis. There are about 3,600 to 7,300 new cases of silicosis every year. Note: This is a progressive illness that will continue to worsen even after exposure to silica has stopped. While it may take years for these diseases to show up, workers should be on the lookout for certain symptoms like a chronic dry cough and shortness of breath. These disabling, irreversible and at times fatal diseases occur when silica particles are inhaled by workers. As a result, nodules start growing and can become so large that they impede normal breathing.

concrete safety

Dust Control Checklist

How to protect your crew:
1. Prevent dust from being released in the air by using water or vacuums at the source.
2. When water and vacuums are not available use a respirator.
3. Replace sand with aluminum oxide for blasting.
4. Use a wet abrasive blaster that mixes water with media before leaving the nozzle.
5. Avoid eating, drinking and smoking in dusty area to reduce, wash face and hands first.
6. Use disposable clothing or wash work clothes at the work site.
7. Shower and change into clean clothes before leaving the job site to avoid contamination.
8. Do a periodic lung screening.

With over 40 years of experience in the industry, we know the importance of safety at work. We also know that using the right pump for the job means even greater safety, better results and more savings in the long run. So if you are looking for a great deal on concrete or plaster pumps, give us a call at (503)283-2105  or visit our website.

Additional reading:
Concrete Safety procedures
Maintenance Tips for gunite
Work Safely with Silica 

Share