Portland cement is the incredible material that has transformed our built environment perhaps more than any other. Cement is the component that bonds concrete together, and since its invention in the middle of the 18th century, Portland cement has become one of the most widely used cements for general purpose construction concrete across the world. The low cost and easy availability of Portland cement's constituents have made it an accessible and effective material for construction the world over. The Conco Companies is a leading commercial concrete contractor in Portland, Oregon that has situated itself in the long history of concrete as an innovator in the evolving technologies of the field.
First developed in Britain, Portland cement is named after its similar appearance to Portland stone, which was then quarried on the Isle of Portland in Dorset, England. According to Robert Courland's book Concrete Planet: The Strange and Fascinating Story of the World's Most Common Man-Made Material, it was first named by Joseph Aspdin who obtained the original patent for Portland cement in 1824. Though Aspdin began the work of creating Portland cement, there was significant refinement of the process still to do. Joseph's son William Aspdin is regarded as the creator of the Portland cement we use today, as he pioneered many improvements to the process through the 1840's.
Portland cement is created by mixing limestone or chalk with shale, clay, or slate, as well as silica sand and iron ore. The most common process for creating Portland cement is called the dry process. In the dry process, this mixture is heated at temperatures approaching 2,700 degrees Fahrenheit in massive cylindrical kilns that are slightly tilted to allow the components to gradually descend the kiln toward the heating element. According to the Portland Cement Association, kilns can be up to 12 feet in diameter, large enough to fit a car, and can be up to 40 stories tall. As the mixture heats up gases are released, a new substance known as clinker falls out of the heated lower end of the kiln. This clinker material, about the size of marbles, is then cooled and mixed with a 3% gypsum and limestone mixture and then grinded to create cement.
It is amazing that natural and readily available materials can create such a ubiquitous bonding material for construction. Without the invention of Portland cement and the continued innovations in concrete mixing and placement, the built environment that has been created over the last 150 years and the roads and cities we know today may not have been as affordable or durable.
The Conco Companies are a leading supplier of concrete services for the Western U.S. We got our start in the Bay Area in 1959 by offering clients the best value on a wide range of concrete services and products. Since that time, we have taken a leading role as one of the top concrete contractors in the region. We have four regional offices serving California, Nevada, Washington, Oregon and Colorado.
Foundations are among the most important structural components of your house but certainly the least visible. Foundations distribute the weight of your home's walls to the ground below to maintain the structural integrity of your home. Yet you only see your foundation when you are in your basement. Most foundation issues are caused by water eroding the soil beneath your home, though in the Bay Area, home foundation cracking can occur due to the shifting soil from the many small earthquakes in the area each year.
Keeping an eye on your foundation
It's important to keep an eye on your foundation by noting symptoms of home foundation problems. The first signs in your home relate to uneven walls and floors. For example, sticking doors or windows, gaps in molding or caulking, sloping floors, or bowing basement walls can all be indicators that your foundation needs attention. Additionally, visible cracking or sinking of the foundation itself need to be addressed promptly.
Identifying the cause of the problem
The first step to solving a foundation problem is identifying the cause. While you can repair an initial foundation issue with a variety of strategies, understanding the cause will give you an idea of the scope and severity of the problem. It is not fun to discover a foundation issue once, let alone realizing years later what was once a minor problem has become severe because the root cause was not mitigated initially. Hiring a general contractor or a structural engineer to survey your property and foundation is the best way to determine the problem. This small upfront investment could give you the peace of mind of knowing the repair strategies that make sense for you and will last.
Foundation Repair Options
Not all foundation issues require a new foundation. While that may be the case in some situations, particularly for foundations built before 1960 that are not up-to-code and susceptible to earthquakes, there are proven repair options as well. In a case where the soil beneath the house is truly stable, simply fixing cracks and watching for any future shifting may be the best course of action. In general, a cracking foundation indicates that the soil beneath the home is changing and the foundation needs additional support. This can be done by slabjacking or piering. In slabjacking, a foundation that is sinking can be lifted by injecting grout beneath it to reproduce the original supporting force the foundation was built on. Piering includes placing mechanical jacks into the soil beneath the foundation to provide a sturdy surface for the foundation. The best method of repair depends on the cause and extent of foundation cracking.
Inspecting and fixing a foundation should only be done by a professional general contractor or home remodeler. Serving the Bay Area since 1983, Mares & Dow Construction are experts at inspecting and fixing foundation issues found in the San Francisco Bay Area. Save yourself time and call us today to schedule an appointment for your foundation repair.
This weekend, why not pick up some reclaimed lumber from The Lumber Baron and build a picnic bench in preparation for summer fun with your friends and family? Reclaimed redwood is a popular favorite for outdoor furniture, and we have an excellent selection of other reclaimed lumber as well. The Lumber Baron specializes in reclaimed redwood, Douglas fir, and other hardwoods carefully selected from decommissioned structures all over the West Coast and beyond.
Do It Yourself Variety
When you are building it yourself, you have dozens of plans available to choose from, or you could design your own. To keep the appearance of the lumber uniform, it is generally a good idea to build a complete set rather than replacement benches. Keep in mind that most plans will not be tailored for reclaimed lumber, but all you have to do is substitute your material with what the plan calls for.
Rustic Style With Reclaimed Lumber
Old growth heartwood lumber has a different appearance than the redwood material being sold at those big box stores. The material is denser, making it less susceptible to mildew, rot, or insect infestation. Reclaimed material is also less likely to warp, split or crack, owing to the fact that it has had decades to cure. When you factor those benefits in with the depth and color of the lumber, it is easy to see why reclaimed redwood is an excellent choice for all of your weekend projects.
Using Reclaimed Lumber
When you build with reclaimed lumber, you have the option of sealing, painting, or leaving the surface bare. Any of these are probably fine as far as the benches go, but the table itself should be sealed to help reduce contaminants. Old growth material is naturally resistant to most pests, but sanding and sealing with polyurethane will make the surface easier to clean and help prevent stains related to spills. For best results, use lumber grade “CAH,” or Clear All Heart.
Whether you are building a privacy fence, picnic table benches, or a pergola, The Lumber Baron has the right lumber for your project. We sell material in larger dimensions than many bigger lumber companies, and our on-site lumber mill means we can custom mill lumber to meet your demanding specifications.
From the mid-1800's when concrete began to gain traction as the standard building material, innovation has transformed it from a costly, slow, handmade process to the inexpensive, sophisticated, industrial process it is today. Here are a few of the technologies that have made that transition possible along the way.
Industrial scaling of component development
Before construction machinery was invented, cement and concrete needed to be made by hand. Cement itself requires limestone, sand, and clay to be fired in a kiln at 2,700 degrees Fahrenheit while adding iron and gypsum. This was once a labor-intensive process. Now cement is produced at an industrial scale with kilns up to 12 feet in diameter and up to 40 stories tall. Innovations in cement and concrete production have worked in tandem with the increasingly efficient mining technology used to acquire cement's raw materials and the aggregate needed to combine with the cement to make concrete. These technologies have allowed more concrete mix to be prepared with less expense than ever before.
Concrete itself is susceptible to cracking and can break when torque is applied to it. You would be able to observe this concept if you held a small piece of concrete in your hands and twisted it apart: it is easy to snap into two pieces. However, you would not be able to squeeze and break it at all. This is where concrete's strength lies. Concrete can withstand extremely high compressive forces. This makes it ideal for holding up entire buildings, but vulnerable to cracking if soil shifts. The solution to this is reinforcing concrete with steel that has a high tensile strength, which combats any bending or shifting a building may experience. This technology was originally developed in the late 1800's and has evolved into pre- and post-tensioning systems that allow for less concrete to be used, while still being able to handle greater loads across more distances.
Project planning software
One of the more recent innovations which has accelerated the efficiency of concrete construction is construction management software. Software now assists in many of the project planning phases, including the design and engineering of the structure. One of the major software components that has allowed concrete contractors to be nimbler and cost effective is material requirement planning, or MRP. This software system considers a contractor's current inventory and production schedule to determine a more precise volume of components that need to be purchased for every project.
The Conco Companies goal is to be the top supplier of concrete services in the Western U.S. and to bring our expertise and professionalism to each project. We continue to upgrade and expand our facilities to better serve the growing market for commercial, industrial, educational, parking structure projects and other development. For the best value and quality, trust your project to one of the area’s leading lightweight concrete contractors.