Marco Concrete Lifting, Inc. can provide concrete pumps and experienced operators to handle any concrete pumping job; “big or small we do ‘em all”. In the concrete industry there are basically two different types of pumps, a trailer mounted pump and a truck mounted boom pump.
Generally, trailer pumps are used on small to medium volume projects such as pads, small walls, floors. They are also the choice for shotcrete application and some pressure grouting. Trailer pumps pump though hoses or steel line if needed ranging from 2” to 5” in diameter and can span several hundred feet. The trailer-mounted pumps are used to get into places that larger trucks cannot; where tighter access is required.
Boom pump trucks are equipped with higher volume pumps, usually rated above 100 yds/hr and have a roll and fold boom. They have the ability to place larger amounts of concrete more efficiently without constantly breaking down and setting up pipe or hose.
A boom truck can reach over 100’ over the front of truck making placement much easier.
This photo shows a piering project at about midway through of a local business’s building/storefront
A weak foundation places a building and its occupants at risk. Cracks that become larger over time in the walls should not be ignored. Once a foundation failure is established as the cause, a structural expert will usually recommend one of two techniques to foundation piering.
There are many reasons that building foundations begin to weaken and distort. Probably the main cause of foundation failure is the improper construction of a building on unstable soil especially where the soil contains large amounts of clay. Another key characteristic of foundation weakness is the tendency for foundation failure to take place in wet areas or regions close to a large water body such as a lake, sea or swamp. The wet clay or waterlogged soil around and beneath the building foundation starts to disengage the foundation from its firm attachment to the soil over time.
This photo shows two hydraulic rams mounted to piering brackets and driving pier pipe. They are part of an array of piers being installed on this building.
How do you tell if a building is experiencing foundation failure?
One of the major signs of a weakening and irregular foundation is the gradual appearance of diagonal cracks on the inside and outside of the building’s walls usually but not always radiating up from the ground or the corners of window or door frames. You may also notice doors and window frames start to develop gaps around the frame. Cracks begin to appear in the floor as they are forced into distortion as the floor gradually loses its regular shape. When you start to see these signs, consult a structural expert immediately to establish whether your building is indeed succumbing to foundation failure.
Foundation piering is the process of attaching steel piles to the structure’s footers to help firm up a weak or collapsing building foundation. In order for the steel piles to support the collapsing or unstable foundation structure, they must extend far enough down to reach either bedrock or load-bearing strata. The hydraulically installed steel piles become the new permanent foundation of the structure.
Basic Push Piering project step-by-step:
The piers in this photo have had rebar installed in them and have been grouted with hi-strength concrete to add some extra stability. They are ready to be backfilled in this picture.
- 1Crews dig down to just below footer depth at predetermined locations exposing a portion of the footer.
- 2Footer is prepared to accept a piering bracket. The footer must be faced back flush to the wall in order to achieve proper geometry thus proper lifting characteristics.
- 3A special bracket is then attached to the footer which allows for the piering pipe to be hydraulically installed through it.
- 4Special hydraulic rams are mounted to the brackets and sections of piering pipe are “pushed” or driven into the earth. Piers are driven until enough resistance is met to stabilize or even lift the foundation.
- 5After all piers are properly pressured up they are bolted off to the bracket and become a permanent integral part of the foundation.
Helical piering (also known as drilled piering) is recommended where the structure being repaired is not very heavy. These lighter structures don’t have enough weight to allow push piers to drive deep enough to be effective. Helical piles don’t have to go as deep because the structure’s weight is supported by the blades of the pile. The process for installing helical piles is a little different.
This is a photo of a pier assembly that is fully pressured and locked off, ready to be backfilled.
Basic Helical piering project step-by-step:
- 1Crews dig down to just below footer depth at predetermined locations exposing a portion of the footer.
- 2Footer is prepared to accept a piering bracket. Footer must be faced back flush to the wall in order to achieve proper geometry thus proper lifting characteristics.
- 3The helical pile is driven using a special hydraulic drive motor (usually mounted on a small excavator) to a predetermined torque specification. Extensions are added as needed to achieve proper depth and pressure.
- 4The same special bracket used in push piering is then slipped onto the pile and attached to the footer allowing the hydraulic rams to be mounted to the brackets. The rams supply the hydraulic pressure to stabilize or lift the structure.
- 5After all piers are pressured up they are then bolted off to the bracket and become a permanent integral part of the foundation.
Pre-construction piles are being installed using an excavator-mounted hydraulic torque motor at a future Natural Gas Transmission Plant near Clarksburg, West Virginia.
Pre-construction piles are being installed uing an excavator-mounted hydraulic torque motor at a future Natural Gas Transmission Plant near Clarksburg, West Virginia.
The concentrated cluster of 21 helicals now installed and capped with grade beam caps. Next, they are tied into rebar cages before the corner of the parking building is formed and poured. CAMC Memorial hospital complex in Charleston, West Virginia.
In some cases soil quality or compaction isn’t good enough to support the weight of some structures. Marco Concrete Lifting can install preconstruction helical piles to increase the strength of a new structure’s foundation substantially. This process has little or no negative ecological impact on the surrounding areas. Helical piles are installed using an excavator mounted hydraulic torque motor. This equipment does not damage the grounds and generates almost no soil spoils.
Helical piles are installed directly in the ditch where the footing will be before it is poured. A grade beam or rebar cap is then attached to the top of the installed pile for rebar or other steel to be attached to. The concrete is poured over the piles and rebar making the pile a permanent part of the foundation.
This is a photo of a machine-base pressure grouting project in progress at the Buffalo, WV Toyota manufacturing facility.
There are a few different types of grouting that are done under pressure. This makes the term “pressure grouting” a bit redundant, but it is used nonetheless. However, the idea behind these types of grouting is pretty similar.
The crew is preparing one of the grout injection ports inside the Buffalo, WV Toyota manufacturing facility.
Pressure Grouting will not only require a licensed contractor but it will require a contractor that is very knowledgeable and experienced in the grouting field. The fact is pressure grouting is not a simple process. It is extremely complicated and the slightest error could cause problems such as minor cracking in the concrete, to major destruction or even physical injury. Repairing damage or replacing damaged property can be very expensive, so you want to do everything you can to preserve it.
That being said, you need to find an experienced, professional company to perform the grouting project that you are planning. Using a company based on price alone is the worst decision you make. Get to know the company before they do any work for you. Be sure they offer a warranty on their work. As long as you follow those simple steps and be critical of your selection, you should have absolutely no problem finding a good, reputable company that will do an exceptional grouting job for you.
Here you can see a pressure grouting project in progress to fill voids in a bridge caisson/pier.
Marco Concrete Lifting can professionally perform any type of pressure grouting project you may have. Our staff has many years of experience plus a very large pressure grouting knowledge base. Contact us today and experience a professional pressure grouting contractor. You won’t be disappointed!
Rebuilding a small bridge using gunite to contain and waterproof the structure.
You have probably heard of Shotcrete or Gunite. They are types of pneumatically applied concrete. They have several uses from cosmetic to structural, commercial and residential. After application they can both either be trowel-finished or left as shot from the nozzle. The basic ways shotcrete and gunite are applied has not changed much over the years. They are both pneumatically applied with a nozzle rather than poured from a truck. Due to the specialized equipment, knowledge and experience required it is not something that the average person would do. You definitely want to make sure you seek a professional company for any project involving shotcrete or gunite.
Shotcrete is usually used in structural situations because it has aggregate in it making it stronger. Gunite is strong also but not as strong as shotcrete due to the fact that it does not have aggregate in it.
This photo shows a temporary wall constructed using a combination of vertical piers lagged to horizontal tie-backs and capped by steel plates, then finally encased in gunite. This was done in reparation for a large addition to be built.
The preparation and application are different. Shotcrete is usually mixed off site then delivered to the construction site by a ready-mix truck much like concrete. Gunite is mixed on site. The application method for shotcrete known as a “wet application involves the delivery truck loading the concrete pump hopper then the mix is pumped through the hose to the nozzle where compressed air is introduced to shoot it out of the nozzle. The nozzle man doesn’t have control over the mix ratio except for air pressure at the nozzle.
Marco Concrete Lifting installed a type of gunite to repair delaminated concrete on the underside of this Interstate overpass near Huntington, West Virginia.
The application method for gunite is known as “dry application”. The dry gunite is put into the gunite machine where it is metered. Then compressed air pushes it through the hose to the nozzle where water is introduced allowing the nozzleman to have some degree of control over the mix ratio.
Remember to choose a company that will get the job done right. This isn’t the siding on your house, this is a significant part of your property that is for all intents and purposes permanent, and you will have to look at it for a very long time. A shotcrete installation can actually define a house, so with that in mind, how do you want your house defined? You want a great job that not only looks professional, but stands up to the elements no matter which you choose, shotcrete or gunite. It may cost a bit to install, but you’ll be glad that you spent the money later on.
Slabjacking is an alternative to replacing sunken or uneven concrete, restoring sunken concrete slabs to their original grade. The name, slabjacking, (also referred to as mudjacking or pressure grouting) is the process of jacking or raising up a slab of cement and restoring it to its original level. This process can involve lifting one solid piece such as cement steps, or readjusting several pads. Slabjacking or mudjacking has been in common use for about 50 years.
Selecting the proper pump and proportioning grout are critical to success, a lesson learned in the 50-year history of slabjacking. We have a wide variety of equipment available to our customers to better solve their concrete lifting problems.
Why do slabs fail? The primary culprit is water, usually not enough, or an unequal distribution. The most common reason concrete settles is due to water causing the soil underneath to compact under the weight of the concrete and its many uses. Concentrated loads, such as buildings or slabs can literally squeeze air and water from soils. Sinking foundations, slab cracks, and foundation failures are very common.
Slab Jacking is a great alternative to removing and replacing concrete that has become a hazard, holding water or causing water to drain back toward buildings. A cracked and damaged slab can be quickly repaired. Since slabs are not being removed, there is little mess, no inconvenience or color change. The area can be used immediately after the slabs are raised (please allow 24 hours in the case of parking pads or garage floors).
Slabjacking is a cost-effective alternative to removing and replacing problem concrete. The alternative requires demolition of the existing slab, pouring new concrete and curing time. Our method allows you to walk on the surface almost immediately after work is completed. With those kinds of benefits, it’s easy to see why slabjacking has become the concrete repair method of choice when it comes to raising concrete that has settled and sunk into the ground.
In slabjacking, your contractor will pump a cement grout underneath the failing concrete slab or foundation in order to raise it up to its original level and provide it with a better sub-surface to set on. The grout is typically comprised of water, Portland cement, or lime and sand. Additives may be used to prevent shrinkage in some rare cases. The “slurry” displaces air pockets, water and water saturated materials, raises the slab and leaves a firm, permanent sub grade. This completely fills any voids, and usually allows raising the concrete to its original height. After the lifting is complete, we clean the area of excess drill tailings and grout, patch the holes with our custom color matching system.
Marco Concrete Lifting technicians have extensive experience with the slab jacking process and monitor the work carefully while in progress. More than contractors, our experts are service professionals who specialize in the field of concrete lifting (slab jacking) and foundation repair. We will be happy to schedule a free inspection and estimate. We have an excellent reputation and stand behind our work.
This photo shows a slope stabilization project utilizing hi-strength ®Tecco wire mesh held in place by helical piles on the slope and grouted tie-back anchors on the wall portion. Also wire rope tensioned across the wall portion.
Marco Concrete Lifting, Inc. has over a decade of experience with slope stabilization and erosion repair methods. Our slope stabilization techniques are the best in the industry and we can help you prevent the erosion of your valuable property. Some of the methods such as soil nails, grouted anchors or helical anchors are used in conjunction with high tensile strength Tecco® wire mesh with a wire rope border to stabilize the slope. Some cases require different methods of repair such as retaining walls, including gabion and crib walls which can also be used to resist further movement of the landslide mass.
This photo shows a slope stabilization project consisting of ®Tecco wire mesh anchored using soil nails and finally a layer of shotcrete with stainless steel fibers in it applied to the surface.
The best method of preserving the integrity of these slopes is through preventative maintenance. Including; debris removal, proper drainage, or even installation of an anchored netting system to prevent rocks or other debris from breaking away and causing property damage.
For centuries trees and other living plants were the only materials available for slope stabilization. Today, these old materials and techniques are still in use as well as newer, more advanced methods being available. One of these methods uses an anchoring array of soil nails, grouted hollow bar or helical anchors holding down pre-tensioned Tecco® wire mesh. Integrating living plant material improves aesthetics, decreases maintenance and results in a system that actually increases in strength over time.
We can evaluate the scope of the problem, recommend the next course of action, arrange for proper soil testing and analysis if needed and provide a quotation for the project cost.