If it has been a while since you last visited Oakland, CA, you are in for a surprise. Over the last few years, Oakland has seen dozens of new construction projects throughout its downtown core and nearby neighborhoods. The Conco Companies have been pleased to be involved in several of them.
One example is the Brooklyn Basin Parcel B Project, which is a 7-story residential housing project from the developer and owner, the Signature Development Group. Along with 241 housing units, the 308,270 sq. ft. building includes 3,000 sq. ft. of ground floor commercial tenant space and 241 parking spaces. The waterfront project is located at the corner of Brooklyn Basin Way and 9th Street and is adjacent to a park. The building’s façade features a range of materials including concrete, metal siding, cement and glass. Conco’s responsibilities on the project included providing concrete pumping, reinforcement, formwork, finishing, shotcrete, and Confoam services. We placed 19,850 cubic yards of Confoam and 8,500 cubic yards of concrete as well as shotcrete. Conco also provided 1,400,000 pounds of rebar and post tension reinforcement. Another couple of projects we recently provided concrete services for are the Hanover Waverly and the Hanover Uptown at Valdez Street and 27th Street. Both projects are developed by the Houston-based owner, the Hanover R.S. Limited Partnership. The Hanover Waverly is a 7-story, mixed-use project that consists of 224 apartments and 22,000 sq. ft. of ground floor retail. The architect, TCA Architects designed the contemporary-style structure to take advantage of the curved lot and highlights the building’s location. The Hanover Waverly also offers below grade parking with 226 parking stalls and has an exterior comprised of high quality materials including stone, brick, glass, metal wall panels and cement plaster. The Hanover Uptown is a 7-story, mixed-use project that consists of 253 residential units including studio, one- and two-bedroom apartments, and more than 33,100 sq. ft. of ground floor retail. For both projects, Conco provided concrete pumping, reinforcement, formwork, finishing, and shotcrete services. Conco is one of the leading suppliers of concrete services for the Western U.S. We got our start in 1959 in the Bay Area by offering clients the best value on a broad range of concrete services and products. Since that time, we have taken a leading role as top concrete contractors in the region. We have regional offices serving California, Oregon, Nevada, Colorado and Washington.
0 Comments
Since the passage of Ordinance 183893 in 2015, the City of Los Angeles has been busy identifying non-ductile concrete buildings that require seismic retrofitting to come up code. Along with all of the other concrete services we provide, The Conco Companies is providing professional seismic retrofitting for pre-1978 non-ductile concrete buildings in L.A.
Utilizing our extensive experience, we have the expertise to strengthen concrete buildings to improve their safety and integrity as well as to preserve the historic or unique design elements of the building. Our portfolio includes several renowned area projects including the 1920s-era L.A. Hall of Justice, the iconic L.A. City Hall and the historic Rose Bowl Stadium. The goal of seismic retrofitting is to reduce structural deficiencies and improve the performance of the targeted non-ductile concrete buildings in the event of an earthquake. Without proper strengthening, these buildings may experience structural failure during and/or after seismic activity. In the case of the award-winning concrete seismic retrofit of Los Angeles’ City Hall, the project required 30,000 cubic yards of concrete, 3,000 tons of structural steel, and 5,000 tons of reinforcing steel. Part of the project included providing reinforced concrete shear walls to strengthen existing masonry walls. Another seismic retrofit and renovation we were proud to be involved with was the $231-million L.A. Hall of Justice project. The building had been extensively damaged in the 1994 Northridge earthquake. During the project, we utilized cost-effective solutions including using shotcrete to construct walls faster and with less material to save both time and money. To ensure the best outcome as well as to minimalize the costs, seismic retrofitting projects require experience as well as innovative thinking and Conco delivers plenty of both to all of our projects. In addition to being one of California’s top commercial concrete contractors, we have over sixty years of experience in the industry. Trust Conco’s expertise to help bring your pre-1978 non-ductile concrete building up to code. Please contact us to learn more. The Conco Companies are one of the foremost suppliers of concrete services for the Western U.S. We got our start in 1959 in the Bay Area by offering clients the best value on a broad range of concrete services and products. Since that time, we have taken a leading role as top concrete contractors in the region. We have regional offices serving California, Oregon, Nevada, Colorado and Washington. At The Conco Companies, our portfolio includes a wide variety of projects that have required the use of various concrete mixes to meet their unique specifications. For projects that require extremely durable and/or high-strength concrete, High-performance Concrete (HPC) is used.
HPC is defined by the American Concrete Institute (ACI) as “meeting special combinations of performance and uniformity requirements that cannot always be achieved routinely using conventional constituents and normal mixing, placing, and curing practices.” The design mix of HPC basically contains the same materials as conventional concrete with the difference being the proportion of the materials added to provide the needed strength and durability. The ACI explains that HPC has a specified compressive strength of 8000 psi (55 MPa) or greater. They add that, “The value of 8000 psi (55 MPa) was selected because it represented a strength level at which special care is required for production and testing of the concrete and at which special structural design requirements may be needed.” In addition to strength requirements, HPC is used in projects that face tough environmental conditions. To achieve a project’s specifications, HPC uses other materials along with the cement such as flyash, ground blast furnace slag or microsilica fume. The characteristics of HPC include low shrinkage, low permeability, a high modulus of elasticity, and high strength. However not all high-strength concrete is high-performance. The HPC used in the construction of bridge decks and highways must contain properties such as high density, low permeability and resistance to environmental conditions. Other projects that benefit from HPC are the columns used in high-rises, especially the ones on the lower floors that will bear the greatest load, shear walls and foundations. Please visit Conco’s website to see some of our impressive projects we have had the honor to be a part of. Also while you are there, take a look at the wide range of premium concrete services we offer. 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. Sources:concrete.org/topicsinconcrete/topicdetail/high%20performance%20concrete An interesting report from the Portland Cement Association (PCA) illustrates the various uses for portland cement as it is one of the key ingredients in concrete. They suggest that while concrete is very important to the way we live, and in fact surrounds us, it is often overlooked. They explain that concrete “makes our homes and offices durable and more resilient in natural disasters, it makes our roads and bridges strong and last longer, and thanks to its permanence and energy efficiency, it helps sustain our environment.”
From their illustration, the PCA’s breakdown of how concrete is used includes 8.4% on water and waste systems, 8.9% for industrial and commercial buildings, 27.5% on one-and-two family houses, and 30.8% on the construction of highways, streets and bridges. The other 22.1% is used to build offices, hotels, hospitals, religious institutions, educational institutions and public utilities. Concrete is a mixture of cement paste (cement and water) and coarse and/or fine aggregate. Almost all modern cement is portland cement, which was patented in 1824 by the Englishman, Joseph Aspdin, who named it for its similarity to a building stone quarried on the Isle of Portland. The PCA also describes the various components of concrete as containing 7 to 15% cement, 14 to 21% water, 60 to 75% of aggregate and as much as 8% of air. At The Conco Companies, we have been involved in a wide range of projects from towering skyscrapers, to mixed-use high-rises, hospitals, educational, public utilities and parking structure projects. Conco Pumping is one of the largest pumping and belting companies in the United States and has a reputation for delivering first-class concrete pumping services since 1975. At Conco Reinforcing, we own and operate two state-of-the-art facilities that give us the resources to be a single source for all your rebar fabrication and installation needs regardless of the project size. Please visit our website to learn more about the various concrete services offered by Conco. Conco is one of the leading concrete contractors in the Western U.S. and offer a wide range of quality services and products. Our experience includes providing services for commercial, educational, parking and other construction development as well as public works projects. We serve California, Washington State, Oregon, Colorado and Nevada. Source: cement.org/civilization The Conco Companies’ Martinez facility was recently honored as a recipient of the Central Contra Costa Sanitary District’s Pollution Prevention Award. All private businesses and organizations located within the Central San’s service area are eligible to enter the annual event. Award recipients are recognized for going above and beyond in their business practices in regard to pollution prevention and environmental protection.
The steps the Martinez facility took that helped them to receive the award include using recycled water to wash their trucks. The facility is also pretreating the water before it enters into the storm drain with an innovative sand-oil interceptor and has installed a new sawdust collector. Another thing the facility has done is to install solar panels and made the change to LED lights to help reduce the amount of electricity they are using. Conco is honored to receive this award as we are committed to reducing the environmental impact of our operations throughout our entire organization, and whenever possible we invest in and implement “green” technologies. We understand that these decisions not only make good business sense but can make a difference in the environment as well as to the health and wellbeing of our workforce, other tradespeople and the general public. Please visit the Conco website to learn more about one of the largest commercial concrete contractors in the country. We have an exceptional team of talented professionals that know to create innovative, cost-effective solutions for the most challenging jobs. Contact the experts before you start your next project. Conco is a leading supplier of concrete services for the Western United States. We have built our reputation with superior concrete formwork, reinforcing, place and finish, shotcrete and other ancillary services that benefit from our vast experience. Our concrete services include commercial, educational, parking and other construction development as well as public works projects and highways. The Conco Companies have four regional offices to serve California, Oregon, Washington, Nevada and Colorado. Recently The Conco Companies announced the topping out of the East County Detention Center, a 500,000 SF expansion and replacement to the existing Riverside County Jail. The project’s General Contractor is Clark Construction and the architect is HOK. The $330 million project will add another 1,626 beds to the facility once it is complete.
Since the jail is located in Indio, CA, one of the most challenging aspects to the job was safely dealing with an average temperature of around 100°F and sometimes reaching as high as 120°F. To ensure the safety of all the workers, we had a full-time safety manager on site. Furthermore, all Conco employees as well as our subcontracted employees followed the ACI’s Hot Weather Concreting procedures. Workers were provided with lots of water, rest and shade as well as educated to recognize the signs of heat-related illnesses in themselves or in a co-worker. Our hard-working crews formed, pumped and placed 55,000 CY on the project, which also includes the construction a 990-stall concrete parking structure adjacent to the new facility. We also used our pumps to pour piles 60’ below ground-level for Becho, another one of our trade partner on the job. Phase One of the project includes a three-story administration and support building with an extension of the existing below grade tunnel. Phase Two includes a four-story structure consisting of two housing units and mezzanine levels. The entire project is expected to be completed this winter. To celebrate the topping out of the structure and as a thank you to our crews and their families, we held a Pre-Father’s Day Company picnic at Prado Dam. Over 250 people showed up to enjoy the hotdogs, BBQ, and other treats. Prizes were awarded and games were played by the kids and grownups alike. Please visit Conco’s website to learn more about the various scope of our large portfolio and the range of our professional concrete solutions. The Conco Companies are a leading supplier of concrete services for the Western U.S and we got our start in the Bay Area in 1959. Our success has come from offering clients the best value on a wide range of concrete services and products and we are now one of the region’s top commercial concrete contractors. We currently serve the areas of Southern and Northern California, Oregon, Washington Colorado, and Nevada. Over the last several decades, there have been advancements in shotcrete technology and improvements in the equipment that have resulted in a material that is perfectly suited for more and more applications. While shotcrete virtually eliminates the forming process, it still offers the same structural characteristics as traditional cast-in-place walls. This means that projects using shotcrete are typically completed faster, which saves both time and money.
However to ensure you get the best finished product, you need to use a company that is experienced with the process as well as the proper equipment and skilled crews to place it. At The Conco Companies, we are proud to say we have all three – the experience, equipment and skilled nozzlemen - and our portfolio includes successfully completing a diverse range of projects using shotcrete. Common applications include shear walls, retaining walls, and architectural walls to slope pavement and soil nailing as well as sites with extreme operating environments such as hydroelectric plants along with many other uses. One project we are currently working on is providing shotcrete services for the new I-5NB HOV lane in Tacoma, WA. For this project, we are using a specialty shotcrete technique that involves carving a design on the shot-face of the retaining walls. To increase efficiency, our crews are doing all of the carving from lifts. This project is a perfect example of the cost-efficiency of shotcrete over traditional cast-in-place concrete as it is saving the project an enormous amount of both time and labor costs. On another new project in Portland, OR, Conco is providing a full range of concrete services including cost-effective shotcrete. The 14th & Glisan is a 16-story, mixed-use building. Among the scope of the job includes using shotcrete on a three-level below grade parking structure. Please visit our website for other shotcrete projects we have posted as well as those using our other services. Conco is one of the leading concrete contractors in the Western U.S. and offers a wide range of quality services and products. While we tackle projects both big and small, our experience includes providing the complete concrete package for the Levi’s Stadium along with other notable projects. We serve California, Washington State, Oregon, Colorado and Nevada. Conco Reinforcing has been extremely busy over the last couple of years and our services have been employed on a number of different types of projects. From airports to mixed-use high-rises, public works, highway projects and others, our two fabrication plants and installation crews have remained hard at work.
One recent project from The Conco Companies includes providing a full range of concrete services for the new five-level Midfield Satellite Concourse North and the Baggage Optimization Project (BOP). This will be a large addition to LAX’s Tom Bradley International Terminal (TBIT). Along with providing concrete reinforcement, we are also providing concrete pumping, formwork and shotcrete. The Conco Companies also recently began work on the new Tacoma Convention Center Hotel in Tacoma, WA. For the $20 million mixed-use development, Conco services will include the concrete reinforcement along with concrete pumping, formwork, shotcrete and finishing. We were selected for the job due to our successful portfolio of big projects as well as our proven ability to handle aggressive deadlines. When finished, the high-rise will be the second tallest building in the city. Conco Reinforcing has also done a lot of highway work over the last couple of years including the $2,200,000 Highway I80/SR12 Separation Interchange in Cordelia, CA. Working with Viking Construction, the project was started in November 2014 and completed in 2016. Another project was the $6,700,000 Highway 4/I-5 Expansion in Stockton, CA with Brosamer & Wall that was also complete in 2016. This is just a few of the construction projects up and down the West Coast that have taken advantage of Conco’s premium concrete services. Our large resources and talented pool of employees allow us to successfully take on the most challenging projects. The Conco Companies are one of the foremost suppliers of concrete services for the Western U.S. We got our start in 1959 in the Bay Area by offering clients the best value on a broad range of concrete services and products. Since that time, we have taken a leading role as top concrete contractors in the region. We have four regional offices serving California, Oregon, Nevada, Colorado and Washington. The strength of concrete can be increased by a number of methods including using a higher grade of cement or a mineral admixture such as ground granulated blast furnace slag (GGBS). It can also be strengthened by using a low water to cement ratio (W/C) as well as by using well-graded angular aggregates.
Adding more cement to the mix or reducing the ratio of water to cement in the cement paste are two of the easiest ways to strengthen concrete. “Every desirable physical property that you can measure will be adversely affected by adding more water,” so explains the Portland Cement Association. The strength of concrete is also influenced by the quality of raw materials, the ratio of coarse/fine aggregate, temperature, relative humidity, compaction of concrete and the curing process. The quality of the aggregate is recognized by the size, shape, texture and strength of the material and the coarse/fine aggregate ratio will determine the amount of water that is needed. When the amount of fine aggregate is increased in relation to the coarse aggregate, the aggregate surface increases and demands more water. This means the water/cement ratio is increased, which decreases the compressive strength of the concrete. The cement used in the mix should be stored under dry conditions and be manufactured using the most appropriate standards. Even the purity of the water used in the mix can have an effect on the strength of the concrete. Another factor that impacts strength is the compaction of concrete because if there is poor compaction of the plastic concrete; air is entrapped and reduces the strength of the concrete. If concrete contains 10% trapped air, it is estimated that the strength of the concrete can be affected by as much as 30 to 40%. Furthermore, to allow concrete to reach its maximum strength, concrete contractors take into account the air temperature, relative humidity and wind speeds at the time the concrete is poured and in the early curing period. Higher temperatures allow concrete to gain strength more quickly but the final strength is actually lower when hydration occurs at too fast of pace. It also sets up the danger of shrinkage and cracking. Newly placed concrete may be periodically ponded, sprayed, or misted with water or a membrane-forming curing compound or covered with curing sheets. At The Conco Companies, we are one of the leading concrete contractors in the Western U.S. and offer a wide range of quality services and products. Our experience includes providing services for commercial, educational, parking and other construction development as well as public works projects. We serve California, Washington State, Oregon, Colorado and Nevada. Sources: quora.com/What-are-some-ways-to-increase-the-strength-of-a-concrete cement.org/for-concrete-books-learning/concrete-technology/faqs theconstructor.org/concrete/factors-affecting-strength-of-concrete/6220/ While there are many applications in which lightweight concrete is the most appropriate choice so are there as many that require heavyweight concrete. Lightweight structural concrete is made using lightweight coarse aggregate and/or lightweight fine aggregate. It typically has a density of approximately 105 pounds per cubic foot as compared to that of normal concrete mixes that have a density of 150 pounds per cubic foot. A common use for lightweight concrete is to reduce the overall load or weight of an entire concrete structure such as on bridge decks, beams, slabs and walls of concrete structures.
Heavy natural aggregates or manufactured aggregates such as iron or lead shot are used to manufacture heavy concrete and offers a density in the range of 270 pounds per cubic foot. There are a number of applications where heavyweight concrete is used including underground garages, as counterweights, radiation shielding in medical or nuclear facilities, and offshore for ballasting in pipelines. Recently another reason for using heavyweight concrete is being implemented by the Crossrail track slab construction project in London, UK. The contractors are using a dense, heavyweight concrete as a sound barrier and to mitigate vibrations across a certain part of the track slab that runs underneath a business section near the Bond Street station. This particular section of track includes several recording studios that rest above it that do not wish to have any sound interfere with their work. The concrete mixture took 12 months to develop and included laboratory and plant trials. The end product contains “MagnaDense, which is an aggregate that is around twice as dense as normal aggregate.” Develop by LKAB Minerals, the natural aggregate is “manufactured from the iron oxide Magnetiteis and is formed of black ferrimagnetic natural iron oxide (Magnetite).” The Conco Companies’ mission is to be the best supplier of concrete services in the Western United States and to bring expertise, experience and quality to each project. We continue to upgrade and expand facilities to better serve the growing market for public works projects, commercial, parking structures, educational, and other construction development. Sources: giatecscientific.com/knowledge-center/concrete-news/heavyweight-concrete-to-minimize-sounds-and-vibrations/ everything-about-concrete.com/lightweight-concrete.html |
Archives
October 2021
Categories
All
|