Applying Epoxy Injections for Crack Repair

Applying Epoxy Injections for Crack Repair

Step-by-step guide on how to assess the severity of foundation cracks and choose the appropriate repair method.

Overview of the common causes of foundation cracks in residential properties


Sure, here's a short essay on the topic "Overview of the Common Causes of Foundation Cracks in Residential Properties" in a human-like style:
Weather conditions can accelerate foundation problems if left unchecked residential foundation repair service driveway.
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Foundation cracks in residential properties are a common concern for homeowners and can arise from a variety of causes. Understanding these causes is crucial for effective repair, such as applying epoxy injections. One primary cause is soil movement, which can occur due to changes in moisture levels. When soil expands or contracts, it exerts pressure on the foundation, leading to cracks. Poor drainage around the property can exacerbate this issue, as water accumulation near the foundation can weaken the soil and contribute to movement.

Another significant factor is the settling of the house over time. As the soil beneath a house compacts, the foundation may shift slightly, resulting in cracks. This is especially common in new homes as the soil continues to settle after construction. Additionally, the type of soil on which a house is built plays a role; clay soils, for example, are more prone to expansion and contraction with moisture changes compared to sandy soils.

Structural issues within the house itself can also lead to foundation cracks. Overloading certain areas of the house, such as adding heavy furniture or appliances without proper support, can place undue stress on the foundation. Moreover, inadequate construction practices, like using substandard materials or poor workmanship, can result in a weaker foundation susceptible to cracking.

Environmental factors, such as earthquakes or freeze-thaw cycles in colder climates, can also cause foundation cracks. During an earthquake, the ground shakes violently, which can displace the soil and cause the foundation to crack. In regions with freeze-thaw cycles, water seeping into small cracks in the foundation can freeze and expand, further widening the cracks when it thaws.

Lastly, tree roots near the foundation can be a hidden culprit. As trees grow, their roots seek out water and nutrients, sometimes extending under the foundation. When roots absorb water, they can cause the soil to shrink, pulling the foundation with it and leading to cracks.

In conclusion, foundation cracks in residential properties can stem from a multitude of causes, ranging from soil movement and house settling to structural issues and environmental factors. Identifying the specific cause of a crack is essential for determining the most effective repair method, such as epoxy injections, to ensure the longevity and stability of the home.

Explanation of the benefits of using epoxy injections for crack repair


Certainly! Here's a short essay on the benefits of using epoxy injections for crack repair:

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When it comes to repairing structural cracks, epoxy injections have emerged as a highly effective and reliable solution. This method involves injecting a specialized epoxy resin into the cracks, which then hardens to form a strong bond, restoring the integrity of the material. There are several compelling benefits to using epoxy injections for crack repair.

Firstly, epoxy injections provide exceptional strength and durability. The cured epoxy forms a bond that is often stronger than the original material, ensuring that the repaired area can withstand significant stress and load. This is particularly crucial for structural applications where safety and longevity are paramount.

Secondly, epoxy injections offer superior adhesion. The resin penetrates deep into the crack, filling even the smallest voids and creating a continuous, monolithic structure. This ensures that the repair is not only strong but also resistant to further cracking and degradation.

Another significant advantage is the versatility of epoxy injections. They can be used on a wide range of materials, including concrete, stone, and even some types of wood. This makes them a go-to solution for various applications, from repairing residential driveways to fixing commercial infrastructure.

Moreover, epoxy injections are relatively quick to apply and cure. Unlike traditional methods that may require extensive preparation and long curing times, epoxy injections can often be completed in a matter of hours. This minimizes downtime and allows for faster return to use, which is especially beneficial in commercial and industrial settings.

Additionally, epoxy injections are resistant to chemicals and environmental factors. Once cured, the epoxy forms a protective barrier that shields the repaired area from moisture, salts, and other corrosive elements. This enhances the longevity of the repair and reduces the need for frequent maintenance.

Lastly, epoxy injections are aesthetically pleasing. The repaired area can be smoothed and finished to match the surrounding material, ensuring a seamless appearance. This is particularly important in visible applications where cosmetic appeal is a consideration.

In conclusion, the benefits of using epoxy injections for crack repair are manifold. They offer unparalleled strength, durability, adhesion, versatility, speed, chemical resistance, and aesthetic appeal. Whether for residential, commercial, or industrial applications, epoxy injections provide a reliable and effective solution for restoring the integrity of cracked materials.

Detailed steps for preparing the foundation for epoxy injection treatment


Certainly! Preparing the foundation for epoxy injection treatment is a crucial step in ensuring the effectiveness and longevity of crack repair. Here's a detailed guide that walks you through the process in a straightforward, human-like manner.

First and foremost, safety should always be your top priority. Before you start any work, make sure you're wearing the appropriate personal protective equipment (PPE) such as gloves, safety glasses, and a dust mask. This not only protects you from potential hazards but also ensures that you're comfortable throughout the process.

Begin by thoroughly inspecting the crack you intend to repair. Take note of its length, width, and depth. This initial assessment will help you determine the extent of the repair needed and the type of epoxy injection method to use. Whether it's a hairline crack or a more significant fracture, understanding its characteristics is key.

Next, clean the crack meticulously. Use a wire brush or a suitable cleaning tool to remove any loose debris, dirt, or old sealant. This step is vital because the effectiveness of the epoxy injection largely depends on the adhesion of the epoxy to the crack surfaces. A clean surface ensures better bonding and, consequently, a more durable repair.

After cleaning, it's time to widen the crack slightly. This might sound counterintuitive, but it's necessary for the epoxy to penetrate deeply into the crack. Use a crack chaser or a similar tool to open the crack to about 3mm in width. Be careful not to go too deep, as this could damage the surrounding material.

Once the crack is widened, it's crucial to remove any dust or debris created during this process. A vacuum or compressed air can be used for this purpose. Ensuring the crack is free from contaminants is essential for the epoxy to bond properly.

Now, it's time to apply a primer. The primer acts as a bridge between the crack surface and the epoxy, enhancing adhesion. Choose a primer that's compatible with the epoxy you plan to use. Apply it generously along the crack and allow it to dry according to the manufacturer's instructions.

With the primer in place, you're now ready to proceed with the epoxy injection. This involves injecting the epoxy into the crack under pressure, ensuring it fills the entire void. It's a delicate process that requires precision and patience to ensure the epoxy reaches all parts of the crack.

After the epoxy has been injected, allow it to cure. The curing time can vary depending on the type of epoxy used and the environmental conditions. It's important to follow the manufacturer's recommendations for curing times to ensure the repair reaches its full strength.

In conclusion, preparing the foundation for epoxy injection treatment is a detailed process that requires attention to detail and a methodical approach. By following these steps, you can ensure a successful and durable crack repair that stands the test of time. Remember, the key to a successful epoxy injection is in the preparation. Take your time, follow each step carefully, and you'll be rewarded with a repair that not only looks good but also performs exceptionally well.

Description of the epoxy injection process, including materials and equipment needed


Certainly! Here's a human-like essay on the topic "Description of the Epoxy Injection Process, Including Materials and Equipment Needed for Applying Epoxy Injections for Crack Repair":

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Epoxy injection is a highly effective method for repairing cracks in concrete and other substrates. This process not only restores the structural integrity of the material but also enhances its aesthetic appeal. Let's delve into the epoxy injection process, including the materials and equipment needed for this repair technique.

The epoxy injection process begins with a thorough assessment of the crack. This involves measuring the width, depth, and length of the crack to determine the appropriate epoxy type and injection method. Once the assessment is complete, the crack is cleaned to remove any dirt, debris, or loose material. This step is crucial as it ensures that the epoxy adheres properly to the substrate.

Next, the crack is typically dampened with water. This helps the epoxy to flow more easily into the crack and ensures better adhesion. Following this, a primer may be applied to the crack. The primer acts as a bonding agent, enhancing the adhesion of the epoxy to the substrate.

The actual injection of the epoxy is the next critical step. Epoxy is a two-part resin system consisting of a resin and a hardener. These components are mixed in specific ratios, usually provided by the manufacturer, to create a viscous liquid. This liquid epoxy is then injected into the crack using specialized equipment.

The equipment needed for epoxy injection includes an injection pump, which pressurizes the epoxy and forces it into the crack. Injection ports, which are small openings drilled into the crack at regular intervals, serve as entry points for the epoxy. These ports are connected to the injection pump via tubing. Additionally, caulking guns may be used to apply epoxy around the edges of the crack to seal it and prevent the epoxy from leaking out.

As the epoxy is injected, it fills the crack from the bottom up, ensuring that even the deepest parts of the crack are sealed. The injection process continues until the epoxy begins to seep out of the crack, indicating that it is fully filled. Once the injection is complete, the epoxy is allowed to cure. Curing times can vary depending on the type of epoxy used and environmental conditions, but it typically takes several hours to a day for the epoxy to fully harden.

After the epoxy has cured, the injection ports and any excess epoxy are removed or ground down to create a smooth surface. In some cases, the repaired area may be sanded and painted to match the surrounding substrate, ensuring a seamless finish.

In summary, the epoxy injection process is a meticulous yet effective method for repairing cracks in concrete and other materials. It requires a careful assessment of the crack, thorough cleaning, and the use of specialized materials and equipment. When done correctly, epoxy injection not only restores the structural integrity of the substrate but also provides a durable and aesthetically pleasing repair.

Discussion of the curing time and expected results after epoxy injection treatment


Certainly! Here's a human-like essay on the topic of "Discussion of the Curing Time and Expected Results After Epoxy Injection Treatment for Crack Repair":

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When it comes to repairing cracks in concrete or masonry, epoxy injection treatment stands out as a highly effective method. This technique not only seals the crack but also reinforces the structure from within. However, the success of epoxy injection treatment hinges significantly on understanding the curing time and the expected results post-treatment.

Curing time for epoxy injection is a critical factor that determines the efficacy of the repair. Typically, epoxy materials require a curing period that can range from 24 to 48 hours under normal conditions. This period allows the epoxy to harden and bond with the surrounding material, ensuring a robust repair. It's important to note that environmental conditions such as temperature and humidity can influence the curing time. Warmer temperatures generally accelerate the curing process, while cooler conditions may prolong it. Therefore, it's advisable to monitor these factors closely to ensure optimal curing.

The expected results after epoxy injection treatment are quite promising. Upon successful curing, the treated area should exhibit a significant improvement in structural integrity. The crack will be effectively sealed, preventing water ingress and further deterioration. Moreover, the epoxy forms a strong bond with the substrate, enhancing the overall strength of the repaired area. This means that the structure can better withstand stress and load, extending its lifespan.

In terms of aesthetics, epoxy injection offers a seamless repair. Unlike traditional patching methods that may leave visible scars, epoxy injection results in a nearly invisible repair, maintaining the visual integrity of the structure. Additionally, the durability of epoxy means that the repair is long-lasting, reducing the need for frequent maintenance.

In conclusion, epoxy injection treatment for crack repair is a reliable and effective solution. Understanding the curing time and managing environmental conditions are crucial for achieving the best results. With proper application and curing, the treated structure will not only regain its strength but also enjoy enhanced durability and aesthetic appeal.

Tips for maintaining the repaired foundation to prevent future cracks


Maintaining a repaired foundation is crucial to prevent future cracks and ensure the longevity and stability of your home. After undergoing epoxy injection crack repair, it's important to implement a few key practices to keep your foundation in optimal condition. Here are some tips to help you maintain your repaired foundation effectively.

Firstly, keeping the soil around your foundation evenly moist is essential. Fluctuations in soil moisture can lead to expansion and contraction, which may exert pressure on the foundation and cause cracks. Regularly water the soil to maintain consistent moisture levels, especially during dry periods. Installing a proper drainage system, such as French drains, can also help redirect water away from the foundation, reducing the risk of water-related damage.

Secondly, it's important to address any grading issues around your home. Proper grading ensures that water flows away from the foundation rather than towards it. If the ground slopes towards your house, consider regrading the area to create a gentle slope that directs water away from the foundation. This simple adjustment can significantly reduce the likelihood of water seeping into the foundation and causing cracks.

Regularly inspecting your foundation for any signs of new cracks or movement is another crucial maintenance practice. Conduct visual inspections at least once a year, paying close attention to areas where cracks previously occurred. If you notice any new cracks or changes in the foundation's condition, it's important to address them promptly to prevent further damage.

In addition to these practices, maintaining the structural integrity of your home is vital. Ensure that heavy objects, such as furniture or appliances, are evenly distributed to avoid placing excessive pressure on specific areas of the foundation. Additionally, avoid parking heavy vehicles close to the foundation, as the weight can contribute to stress and potential cracking.

Lastly, consider investing in a professional foundation inspection every few years. A qualified inspector can assess the condition of your foundation, identify any potential issues, and provide recommendations for maintenance or further repairs if necessary. Regular professional evaluations can help catch problems early and prevent more extensive and costly repairs in the future.

By following these tips and incorporating them into your regular maintenance routine, you can effectively preserve the integrity of your repaired foundation and minimize the risk of future cracks. Remember, proactive care and attention to your foundation's needs will contribute to a stable and secure home for years to come.



Suspended slab under construction, with the formwork still in place
Suspended slab formwork and rebar in place, ready for concrete pour.

A concrete slab is a common structural element of modern buildings, consisting of a flat, horizontal surface made of cast concrete. Steel-reinforced slabs, typically between 100 and 500 mm thick, are most often used to construct floors and ceilings, while thinner mud slabs may be used for exterior paving ( see below).[1][2]

In many domestic and industrial buildings, a thick concrete slab supported on foundations or directly on the subsoil, is used to construct the ground floor. These slabs are generally classified as ground-bearing or suspended. A slab is ground-bearing if it rests directly on the foundation, otherwise the slab is suspended.[3] For multi-story buildings, there are several common slab designs (

see § Design for more types):

  • Beam and block, also referred to as rib and block, is mostly used in residential and industrial applications. This slab type is made up of pre-stressed beams and hollow blocks and are temporarily propped until set, typically after 21 days.[4]
  • A hollow core slab which is precast and installed on site with a crane
  • In high rise buildings and skyscrapers, thinner, pre-cast concrete slabs are slung between the steel frames to form the floors and ceilings on each level. Cast in-situ slabs are used in high rise buildings and large shopping complexes as well as houses. These in-situ slabs are cast on site using shutters and reinforced steel.

On technical drawings, reinforced concrete slabs are often abbreviated to "r.c.c. slab" or simply "r.c.". Calculations and drawings are often done by structural engineers in CAD software.

Thermal performance

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Energy efficiency has become a primary concern for the construction of new buildings, and the prevalence of concrete slabs calls for careful consideration of its thermal properties in order to minimise wasted energy.[5] Concrete has similar thermal properties to masonry products, in that it has a relatively high thermal mass and is a good conductor of heat.

In some special cases, the thermal properties of concrete have been employed, for example as a heatsink in nuclear power plants or a thermal buffer in industrial freezers.[6]

Thermal conductivity

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Thermal conductivity of a concrete slab indicates the rate of heat transfer through the solid mass by conduction, usually in regard to heat transfer to or from the ground. The coefficient of thermal conductivity, k, is proportional to density of the concrete, among other factors.[5] The primary influences on conductivity are moisture content, type of aggregate, type of cement, constituent proportions, and temperature. These various factors complicate the theoretical evaluation of a k-value, since each component has a different conductivity when isolated, and the position and proportion of each components affects the overall conductivity. To simplify this, particles of aggregate may be considered to be suspended in the homogeneous cement. Campbell-Allen and Thorne (1963) derived a formula for the theoretical thermal conductivity of concrete.[6] In practice this formula is rarely applied, but remains relevant for theoretical use. Subsequently, Valore (1980) developed another formula in terms of overall density.[7] However, this study concerned hollow concrete blocks and its results are unverified for concrete slabs.

The actual value of k varies significantly in practice, and is usually between 0.8 and 2.0 W m−1 K−1.[8] This is relatively high when compared to other materials, for example the conductivity of wood may be as low as 0.04 W m−1 K−1. One way of mitigating the effects of thermal conduction is to introduce insulation (

see § Insulation).

Thermal mass

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The second consideration is the high thermal mass of concrete slabs, which applies similarly to walls and floors, or wherever concrete is used within the thermal envelope. Concrete has a relatively high thermal mass, meaning that it takes a long time to respond to changes in ambient temperature.[9] This is a disadvantage when rooms are heated intermittently and require a quick response, as it takes longer to warm the entire building, including the slab. However, the high thermal mass is an advantage in climates with large daily temperature swings, where the slab acts as a regulator, keeping the building cool by day and warm by night.

Typically concrete slabs perform better than implied by their R-value.[5] The R-value does not consider thermal mass, since it is tested under constant temperature conditions. Thus, when a concrete slab is subjected to fluctuating temperatures, it will respond more slowly to these changes and in many cases increase the efficiency of a building.[5] In reality, there are many factors which contribute to the effect of thermal mass, including the depth and composition of the slab, as well as other properties of the building such as orientation and windows.

Thermal mass is also related to thermal diffusivity, heat capacity and insulation. Concrete has low thermal diffusivity, high heat capacity, and its thermal mass is negatively affected by insulation (e.g. carpet).[5]

Insulation

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Without insulation, concrete slabs cast directly on the ground can cause a significant amount of extraneous energy transfer by conduction, resulting in either lost heat or unwanted heat. In modern construction, concrete slabs are usually cast above a layer of insulation such as expanded polystyrene, and the slab may contain underfloor heating pipes.[10] However, there are still uses for a slab that is not insulated, for example in outbuildings which are not heated or cooled to room temperature (

see § Mud slabs). In these cases, casting the slab directly onto a substrate of aggregate will maintain the slab near the temperature of the substrate throughout the year, and can prevent both freezing and overheating.

A common type of insulated slab is the beam and block system (mentioned above) which is modified by replacing concrete blocks with expanded polystyrene blocks.[11] This not only allows for better insulation but decreases the weight of slab which has a positive effect on load bearing walls and foundations.

Formwork set for concrete pour.
Concrete poured into formwork. This slab is ground-bearing and reinforced with steel rebar.

Design

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Ground-bearing slabs

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Ground-bearing slabs, also known as "on-ground" or "slab-on-grade", are commonly used for ground floors on domestic and some commercial applications. It is an economical and quick construction method for sites that have non-reactive soil and little slope.[12]

For ground-bearing slabs, it is important to design the slab around the type of soil, since some soils such as clay are too dynamic to support a slab consistently across its entire area. This results in cracking and deformation, potentially leading to structural failure of any members attached to the floor, such as wall studs.[12]

Levelling the site before pouring concrete is an important step, as sloping ground will cause the concrete to cure unevenly and will result in differential expansion. In some cases, a naturally sloping site may be levelled simply by removing soil from the uphill site. If a site has a more significant grade, it may be a candidate for the "cut and fill" method, where soil from the higher ground is removed, and the lower ground is built up with fill.[13]

In addition to filling the downhill side, this area of the slab may be supported on concrete piers which extend into the ground. In this case, the fill material is less important structurally as the dead weight of the slab is supported by the piers. However, the fill material is still necessary to support the curing concrete and its reinforcement.

There are two common methods of filling - controlled fill and rolled fill.[13]

  • Controlled fill: Fill material is compacted in several layers by a vibrating plate or roller. Sand fills areas up to around 800 mm deep, and clay may be used to fill areas up to 400 mm deep. However, clay is much more reactive than sand, so it should be used sparingly and carefully. Clay must be moist during compaction to homogenise it.[13]
  • Rolled fill: Fill is repeatedly compacted by an excavator, but this method of compaction is less effective than a vibrator or roller. Thus, the regulations on maximum depth are typically stricter.

Proper curing of ground-bearing concrete is necessary to obtain adequate strength. Since these slabs are inevitably poured on-site (rather than precast as some suspended slabs are), it can be difficult to control conditions to optimize the curing process. This is usually aided by a membrane, either plastic (temporary) or a liquid compound (permanent).[14]

Ground-bearing slabs are usually supplemented with some form of reinforcement, often steel rebar. However, in some cases such as concrete roads, it is acceptable to use an unreinforced slab if it is adequately engineered (

see below).

Suspended slabs

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For a suspended slab, there are a number of designs to improve the strength-to-weight ratio. In all cases the top surface remains flat, and the underside is modulated:

  • A corrugated slab is designed when the concrete is poured into a corrugated steel tray, more commonly called decking. This steel tray improves strength of the slab, and prevents the slab from bending under its own weight. The corrugations run in one direction only.
  • A ribbed slab gives considerably more strength in one direction. This is achieved with concrete beams bearing load between piers or columns, and thinner, integral ribs in the perpendicular direction. An analogy in carpentry would be a subfloor of bearers and joists. Ribbed slabs have higher load ratings than corrugated or flat slabs, but are inferior to waffle slabs.[15]
  • A waffle slab gives added strength in both directions using a matrix of recessed segments beneath the slab.[16] This is the same principle used in the ground-bearing version, the waffle slab foundation. Waffle slabs are usually deeper than ribbed slabs of equivalent strength, and are heavier hence require stronger foundations. However, they provide increased mechanical strength in two dimensions, a characteristic important for vibration resistance and soil movement.[17]
The exposed underside of a waffle slab used in a multi-storey building

Unreinforced slabs

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Unreinforced or "plain"[18] slabs are becoming rare and have limited practical applications, with one exception being the mud slab (

see below). They were once common in the US, but the economic value of reinforced ground-bearing slabs has become more appealing for many engineers.[10] Without reinforcement, the entire load on these slabs is supported by the strength of the concrete, which becomes a vital factor. As a result, any stress induced by a load, static or dynamic, must be within the limit of the concrete's flexural strength to prevent cracking.[19] Since unreinforced concrete is relatively very weak in tension, it is important to consider the effects of tensile stress caused by reactive soil, wind uplift, thermal expansion, and cracking.[20] One of the most common applications for unreinforced slabs is in concrete roads.

Mud slabs

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Mud slabs, also known as rat slabs, are thinner than the more common suspended or ground-bearing slabs (usually 50 to 150 mm), and usually contain no reinforcement.[21] This makes them economical and easy to install for temporary or low-usage purposes such as subfloors, crawlspaces, pathways, paving, and levelling surfaces.[22] In general, they may be used for any application which requires a flat, clean surface. This includes use as a base or "sub-slab" for a larger structural slab. On uneven or steep surfaces, this preparatory measure is necessary to provide a flat surface on which to install rebar and waterproofing membranes.[10] In this application, a mud slab also prevents the plastic bar chairs from sinking into soft topsoil which can cause spalling due to incomplete coverage of the steel. Sometimes a mud slab may be a substitute for coarse aggregate. Mud slabs typically have a moderately rough surface, finished with a float.[10]

Substrate and rebar prepared for pouring a mud slab

Axes of support

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One-way slabs

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A one-way slab has moment-resisting reinforcement only in its short axis, and is used when the moment in the long axis is negligible.[23] Such designs include corrugated slabs and ribbed slabs. Non-reinforced slabs may also be considered one-way if they are supported on only two opposite sides (i.e. they are supported in one axis). A one-way reinforced slab may be stronger than a two-way non-reinforced slab, depending on the type of load.

The calculation of reinforcement requirements for a one-way slab can be extremely tedious and time-consuming, and one can never be completely certain of the best design.[citation needed] Even minor changes to the project can necessitate recalculation of the reinforcement requirements. There are many factors to consider during the structural structure design of one-way slabs, including:

  • Load calculations
  • Bending moment calculation
  • Acceptable depth of flexure and deflection
  • Type and distribution of reinforcing steel

Two-way slabs

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A two-way slab has moment resisting reinforcement in both directions.[24] This may be implemented due to application requirements such as heavy loading, vibration resistance, clearance below the slab, or other factors. However, an important characteristic governing the requirement of a two-way slab is the ratio of the two horizontal lengths. If where is the short dimension and is the long dimension, then moment in both directions should be considered in design.[25] In other words, if the axial ratio is greater than two, a two-way slab is required.

A non-reinforced slab is two-way if it is supported in both horizontal axes.

Construction

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A concrete slab may be prefabricated (precast), or constructed on site.

Prefabricated

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Prefabricated concrete slabs are built in a factory and transported to the site, ready to be lowered into place between steel or concrete beams. They may be pre-stressed (in the factory), post-stressed (on site), or unstressed.[10] It is vital that the wall supporting structure is built to the correct dimensions, or the slabs may not fit.

On-site

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On-site concrete slabs are built on the building site using formwork, a type of boxing into which the wet concrete is poured. If the slab is to be reinforced, the rebars, or metal bars, are positioned within the formwork before the concrete is poured in.[26] Plastic-tipped metal or plastic bar chairs, are used to hold the rebar away from the bottom and sides of the form-work, so that when the concrete sets it completely envelops the reinforcement. This concept is known as concrete cover. For a ground-bearing slab, the formwork may consist only of side walls pushed into the ground. For a suspended slab, the formwork is shaped like a tray, often supported by a temporary scaffold until the concrete sets.

The formwork is commonly built from wooden planks and boards, plastic, or steel. On commercial building sites, plastic and steel are gaining popularity as they save labour.[27] On low-budget or small-scale jobs, for instance when laying a concrete garden path, wooden planks are very common. After the concrete has set the wood may be removed.

Formwork can also be permanent, and remain in situ post concrete pour. For large slabs or paths that are poured in sections, this permanent formwork can then also act as isolation joints within concrete slabs to reduce the potential for cracking due to concrete expansion or movement.

In some cases formwork is not necessary. For instance, a ground slab surrounded by dense soil, brick or block foundation walls, where the walls act as the sides of the tray and hardcore (rubble) acts as the base.

See also

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  • Shallow foundation (Commonly used for ground-bearing slabs)
  • Hollow-core slab (Voided slab, one-way spanning)
  • Beam and block (voided slab, one way spanning)
  • Voided biaxial slab (Voided slab, two-way spanning)
  • Formwork
  • Precast concrete
  • Reinforced concrete
  • Rebar
  • Concrete cover

References

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  1. ^ Garber, G. Design and Construction of Concrete Floors. 2nd ed. Amsterdam: Butterworth-Heinemann, 2006. 47. Print.
  2. ^ Duncan, Chester I. Soils and Foundations for Architects and Engineers. New York: Van Nostrand Reinhold, 1992. 299. Print.
  3. ^ "Ground slabs - Introduction". www.dlsweb.rmit.edu.au. Archived from the original on 2019-11-18. Retrieved 2017-12-07.
  4. ^ "What is a rib and block slab?". www.royalconcreteslabs.co.za. Royal concrete slabs.
  5. ^ a b c d e Cavanaugh, Kevin; et al. (2002). Guide to Thermal Properties of Concrete and Masonry Systems: Reported by ACI Committee 122. American Concrete Institute.
  6. ^ a b Campbell-Allen, D.; Thorne, C.P. (March 1963). "The thermal conductivity of concrete". Magazine of Concrete Research. 15 (43): 39–48. doi:10.1680/macr.1963.15.43.39. UDC 691.32.001:536.21:691.322.
  7. ^ Valore, R.C. Jr. (February 1980). "Calculation of U-values of Hollow Concrete Masonry". Concrete International. 2: 40–63.
  8. ^ Young, Hugh D. (1992). "Table 15.5". University Physics (7th ed.). Addison Wesley. ISBN 0201529815.
  9. ^ Sabnis, Gajanan M.; Juhl, William (2016). "Chapter 4: Sustainability through Thermal Mass of Concrete". Green Building with Concrete: Sustainable Design and Construction (2nd ed.). Taylor & Francis Group. ISBN 978-1-4987-0411-3.
  10. ^ a b c d e Garber, George (2006). Design and Construction of Concrete Floors (2nd ed.). Amsterdam: Butterworth-Heinemann. ISBN 978-0-7506-6656-5.
  11. ^ "What is a polystyrene concrete slab?". www.royalconcreteslabs.co.za. Royal concrete slabs.
  12. ^ a b McKinney, Arthur W.; et al. (2006). Design of Slabs-on-Ground: Reported by ACI Committee 360 (PDF). American Concrete Institute. Archived from the original (PDF) on 2021-05-08. Retrieved 2019-04-04.
  13. ^ a b c Staines, Allan (2014). The Australian House Building Manual. Pinedale Press. pp. 40–41. ISBN 978-1-875217-07-6.
  14. ^ "Concrete in Practice 11 - Curing In-Place Concrete" (PDF). Engineering.com. National Ready Mixed Concrete Association. Archived from the original (PDF) on 4 April 2019. Retrieved 4 April 2019.
  15. ^ "Ribbed Slabs Datasheet" (PDF). Kaset Kalip. Archived from the original (PDF) on 29 March 2018. Retrieved 4 April 2019.
  16. ^ "Ribbed and waffle slabs". www.concretecentre.com. Retrieved 2019-04-04.
  17. ^ Concrete Framed Buildings: A Guide to Design and Construction. MPA The Concrete Centre. 2016. ISBN 978-1-904818-40-3.
  18. ^ Garrison, Tim (19 February 2014). "Clearing the confusion on 'plain concrete'". Civil & Structural Engineer. Archived from the original on 8 May 2019. Retrieved 8 May 2019.
  19. ^ Walker, Wayne. "Reinforcement for slabs on ground". Concrete Construction. Retrieved 8 May 2019.
  20. ^ "Rupture depth of an unreinforced concrete slab on grade" (PDF). Aluminium Association of Florida, Inc. Archived from the original (PDF) on 2020-09-26. Retrieved 2019-05-08.
  21. ^ Arcoma, Peter. "What is a mud slab?". Builder-Questions.com. Retrieved 8 May 2019.
  22. ^ Postma, Mark; et al. "Floor Slabs". Whole Building Design Guide. National Institute of Building Sciences. Retrieved 8 May 2019.
  23. ^ Gilbert, R. I. (1980). UNICIV Report 211 (PDF). University of New South Wales.
  24. ^ Prieto-Portar, L. A. (2008). EGN-5439 The Design of Tall Buildings; Lecture #14: The Design of Reinforced Concrete Slabs (PDF). Archived from the original (PDF) on 2017-08-29. Retrieved 2019-04-04.
  25. ^ "What is the difference between one way and two way slab?". Basic Civil Engineering. 16 June 2019. Retrieved 8 July 2019.
  26. ^ Concrete Basics: A Guide to Concrete Practice (6th ed.). Cement Concrete & Aggregates Australia. 2004. p. 53.
  27. ^ Nemati, Kamran M. (2005). "Temporary Structures: Formwork for Concrete" (PDF). Tokyo Institute of Technology. Archived from the original (PDF) on 12 July 2018. Retrieved 4 April 2019.
[edit]
  • Concrete Basics: A Guide to Concrete Practice
  • Super Insulated Slab Foundations
  • Design of Slabs on Ground Archived 2021-05-08 at the Wayback Machine

 

A mobile home being repaired in Oklahoma
A person making these repairs to a house after a flood

Home repair involves the diagnosis and resolution of problems in a home, and is related to home maintenance to avoid such problems. Many types of repairs are "do it yourself" (DIY) projects, while others may be so complicated, time-consuming or risky as to require the assistance of a qualified handyperson, property manager, contractor/builder, or other professionals.

Home repair is not the same as renovation, although many improvements can result from repairs or maintenance. Often the costs of larger repairs will justify the alternative of investment in full-scale improvements. It may make just as much sense to upgrade a home system (with an improved one) as to repair it or incur ever-more-frequent and expensive maintenance for an inefficient, obsolete or dying system.

Worn, consumed, dull, dirty, clogged

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Repairs often mean simple replacement of worn or used components intended to be periodically renewed by a home-owner, such as burnt out light bulbs, worn out batteries, or overfilled vacuum cleaner bags. Another class of home repairs relates to restoring something to a useful condition, such as sharpening tools or utensils, replacing leaky faucet washers, cleaning out plumbing traps, rain gutters. Because of the required precision, specialized tools, or hazards, some of these are best left to experts such as a plumber. One emergency repair that may be necessary in this area is overflowing toilets. Most of them have a shut-off valve on a pipe beneath or behind them so that the water supply can be turned off while repairs are made, either by removing a clog or repairing a broken mechanism.

Broken or damaged

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Perhaps the most perplexing repairs facing a home-owner are broken or damaged things. In today's era of built-in obsolescence for many products, it is often more convenient to replace something rather than attempt to repair it. A repair person is faced with the tasks of accurately identifying the problem, then finding the materials, supplies, tools and skills necessary to sufficiently effect the repair. Some things, such as broken windows, appliances or furniture can be carried to a repair shop, but there are many repairs that can be performed easily enough, such as patching holes in plaster and drywall, cleaning stains, repairing cracked windows and their screens, or replacing a broken electrical switch or outlet. Other repairs may have some urgency, such as broken water pipes, broken doors, latches or windows, or a leaky roof or water tank, and this factor can certainly justify calling for professional help. A home handyperson may become adept at dealing with such immediate repairs, to avoid further damage or loss, until a professional can be summoned.

Emergency repairs

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Emergencies can happen at any time, so it is important to know how to quickly and efficiently fix the problem. From natural disasters, power loss, appliance failure and no water, emergency repairs tend to be one of the most important repairs to be comfortable and confident with. In most cases, the repairs are DIY or fixable with whatever is around the house. Common repairs would be fixing a leak, broken window, flooding, frozen pipes or clogged toilet. Each problem can have a relatively simple fix, a leaky roof and broken window can be patched, a flood can be pumped out, pipes can be thawed and repaired and toilets can be unclogged with a chemical. For the most part, emergency repairs are not permanent. They are what you can do fast to stop the problem then have a professional come in to permanently fix it.[1] Flooding as a result of frozen pipes, clogged toilets or a leaky roof can result in very costly water damage repairs and even potential health issues resulting from mold growth if not addressed in a timely manner.

Maintenance

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Periodic maintenance also falls under the general class of home repairs. These are inspections, adjustments, cleaning, or replacements that should be done regularly to ensure proper functioning of all the systems in a house, and to avoid costly emergencies. Examples include annual testing and adjustment of alarm systems, central heating or cooling systems (electrodes, thermocouples, and fuel filters), replacement of water treatment components or air-handling filters, purging of heating radiators and water tanks, defrosting a freezer, vacuum refrigerator coils, refilling dry floor-drain traps with water, cleaning out rain gutters, down spouts and drains, touching up worn house paint and weather seals, and cleaning accumulated creosote out of chimney flues, which may be best left to a chimney sweep.

Examples of less frequent home maintenance that should be regularly forecast and budgeted include repainting or staining outdoor wood or metal, repainting masonry, waterproofing masonry, cleaning out septic systems, replacing sacrificial electrodes in water heaters, replacing old washing machine hoses (preferably with stainless steel hoses less likely to burst and cause a flood), and other home improvements such as replacement of obsolete or ageing systems with limited useful lifetimes (water heaters, wood stoves, pumps, and asphaltic or wooden roof shingles and siding.

Often on the bottom of people's to-do list is home maintenance chores, such as landscaping, window and gutter cleaning, power washing the siding and hard-scape, etc. However, these maintenance chores pay for themselves over time. Often, injury could occur when operating heavy machinery or when climbing on ladders or roofs around your home, so if an individual is not in the proper physical condition to accomplish these chores, then they should consult a professional. Lack of maintenance will cost more due to higher costs associated with repairs or replacements to be made later. It requires discipline and learning aptitude to repair and maintain the home in good condition, but it is a satisfying experience to perform even seemingly minor repairs.

Good operations

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Another related issue for avoiding costly repairs (or disasters) is the proper operation of a home, including systems and appliances, in a way that prevents damage or prolongs their usefulness. For example, at higher latitudes, even a clean rain gutter can suddenly build up an ice dam in winter, forcing melt water into unprotected roofing, resulting in leaks or even flooding inside walls or rooms. This can be prevented by installing moisture barrier beneath the roofing tiles. A wary home-owner should be alert to the conditions that can result in larger problems and take remedial action before damage or injury occurs. It may be easier to tack down a bit of worn carpet than repair a large patch damaged by prolonged misuse. Another example is to seek out the source of unusual noises or smells when mechanical, electrical or plumbing systems are operating—sometimes they indicate incipient problems. One should avoid overloading or otherwise misusing systems, and a recurring overload may indicate time for an upgrade.

Water infiltration is one of the most insidious sources of home damage. Small leaks can lead to water stains, and rotting wood. Soft, rotten wood is an inviting target for termites and other wood-damaging insects. Left unattended, a small leak can lead to significant structural damage, necessitating the replacement of beams and framing.

With a useful selection of tools, typical materials and supplies on hand, and some home repair information or experience, a home-owner or handyperson should be able to carry out a large number of DIY home repairs and identify those that will need the specialized attention of others.

Remediation of environmental problems

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When a home is sold, inspections are performed that may reveal environmental hazards such as radon gas in the basement or water supply or friable asbestos materials (both of which can cause lung cancer), peeling or disturbed lead paint (a risk to children and pregnant women), in-ground heating oil tanks that may contaminate ground water, or mold that can cause problems for those with asthma or allergies. Typically the buyer or mortgage lender will require these conditions to be repaired before allowing the purchase to close. An entire industry of environmental remediation contractors has developed to help home owners resolve these types of problems.

See also

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  • Electrical wiring
  • Handyperson
  • Housekeeping
  • Home improvement
  • Home wiring
  • HVAC
  • Maintenance, repair, and operations
  • Plumbing
  • Right to repair
  • Smoke alarm
  • Winterization

References

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  1. ^ Reader's Digest New Complete Do-it-yourself Manual. Montreal, Canada: Reader's Digest Association. 1991. pp. 9–13. ISBN 9780888501783. OCLC 1008853527.

 

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Reviews for


Jeffery James

(5)

Very happy with my experience. They were prompt and followed through, and very helpful in fixing the crack in my foundation.

Sarah McNeily

(5)

USS was excellent. They are honest, straightforward, trustworthy, and conscientious. They thoughtfully removed the flowers and flower bulbs to dig where they needed in the yard, replanted said flowers and spread the extra dirt to fill in an area of the yard. We've had other services from different companies and our yard was really a mess after. They kept the job site meticulously clean. The crew was on time and friendly. I'd recommend them any day! Thanks to Jessie and crew.

Jim de Leon

(5)

It was a pleasure to work with Rick and his crew. From the beginning, Rick listened to my concerns and what I wished to accomplish. Out of the 6 contractors that quoted the project, Rick seemed the MOST willing to accommodate my wishes. His pricing was definitely more than fair as well. I had 10 push piers installed to stabilize and lift an addition of my house. The project commenced at the date that Rick had disclosed initially and it was completed within the same time period expected (based on Rick's original assessment). The crew was well informed, courteous, and hard working. They were not loud (even while equipment was being utilized) and were well spoken. My neighbors were very impressed on how polite they were when they entered / exited my property (saying hello or good morning each day when they crossed paths). You can tell they care about the customer concerns. They ensured that the property would be put back as clean as possible by placing MANY sheets of plywood down prior to excavating. They compacted the dirt back in the holes extremely well to avoid large stock piles of soils. All the while, the main office was calling me to discuss updates and expectations of completion. They provided waivers of lien, certificates of insurance, properly acquired permits, and JULIE locates. From a construction background, I can tell you that I did not see any flaws in the way they operated and this an extremely professional company. The pictures attached show the push piers added to the foundation (pictures 1, 2 & 3), the amount of excavation (picture 4), and the restoration after dirt was placed back in the pits and compacted (pictures 5, 6 & 7). Please notice that they also sealed two large cracks and steel plated these cracks from expanding further (which you can see under my sliding glass door). I, as well as my wife, are extremely happy that we chose United Structural Systems for our contractor. I would happily tell any of my friends and family to use this contractor should the opportunity arise!

Chris Abplanalp

(5)

USS did an amazing job on my underpinning on my house, they were also very courteous to the proximity of my property line next to my neighbor. They kept things in order with all the dirt/mud they had to excavate. They were done exactly in the timeframe they indicated, and the contract was very details oriented with drawings of what would be done. Only thing that would have been nice, is they left my concrete a little muddy with boot prints but again, all-in-all a great job

Dave Kari

(5)

What a fantastic experience! Owner Rick Thomas is a trustworthy professional. Nick and the crew are hard working, knowledgeable and experienced. I interviewed every company in the area, big and small. A homeowner never wants to hear that they have foundation issues. Out of every company, I trusted USS the most, and it paid off in the end. Highly recommend.

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