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Different Proportions to Consider for Concrete Mix

As your construction project progresses smoothly, it’s quite important to consider the right concrete mix proportion. But, as the slurry gets prepared with the addition of cement, sand, and water, the ratio totally depends on the construction project. However, based on prior experience, the building codes offer standard ratios for onsite construction. If you are worried about quality, then you should opt for premix concrete in Brisbane from Reocrete. But, if you are not sure about the ratio, then you should read ahead to learn more about the proportions.

Materials used for preparing concrete

Among the basic materials, concrete always has cement as one of its constituents. While shale, limestone, and other ingredients are burnt to form clinker, the grinder grinds lump to obtain a fine powder. You may come across blended cement at some sites however, this is ideally used for masonry work, ideally for plastering. Apart from cement, aggregate and sand are also major constituents. The ingredients not only enhance structural integrity but also increase compressive strength.

Different types of proportions

  1. Nominal Mix ratios: Many years ago, the ratio of the constituents for concrete was actually based on the amount of cement and aggregate. Since this was considered a fixed ratio, such types of ratios were known as nominal. Ideally, the nominal ratio is 1:1.5:3 for M20 grade concrete and 1:2:4 for M15 concrete. To learn more about concrete prices in Brisbane contact Reocrete today!
  2. Standard Mix ratios: As the contractor may vary the nominal ratio, the overall constitution may differ to some extent. Even though the ratio may enhance strength, the cement may not be suitable for the onsite construction work. Hence, in order to maintain minimum compressive strength, concrete is based on a standard ratio. While you purchase concrete, you may come across different grades like N20, N50, N32, and N25. But, for grades more than 50, the contractor may require special class concrete for the work. Regardless of the concrete mix, every grade is different with respect to its compressive strength.
  3. Designed Mix Ratio: When dealing with a Designed Mix Ratio, an experienced professional determines the precise proportion of the constituents. Moreover, concrete suppliers in Brisbane may follow a rational approach to figure out the proportion with the unique characteristics of the materials. It’s completely normal to use standard or nominal mixes for short-duration jobs. The ratios, in this case, don’t matter when there isn’t any need to carry out control testing.

Finally, for increasing the strength of hardened concrete, it’s important to maintain the water to cement ratio; fine aggregate can be added only when the person is preparing a sticky mix.

Contact steel suppliers in Brisbane at Reocrete, if you have any questions or need any assistance deciding on the right concrete for your construction project!

How to Determine the Tensile Strength of Concrete

When a contractor plans to execute a construction project, it’s important to firstly determine the overall strength of the concrete. Due to various effects and the applied load, the structures built from concrete are prone to tensile cracking. But, on the other hand, it’s advisable to use steel reinforcing mesh Brisbane when the contractor needs to reinforce concrete slabs. So, let’s get into two different kinds of tests and the procedure of measuring the tensile strength of concrete.

1. Split-Cylinder Test

A split-cylinder test is known as a standard test, which enables the contractor to find out the tensile strength indirectly. As the expert starts off with the test, a concrete specimen dipped in water is placed between the loading surfaces of the testing machine. While the load is applied uniformly along the diameter, the testing machine is set to a range between 0.7 to 1.4 MPa/min.

It’s important to note that a plywood strip has to be placed on the lowermost plate. Moreover, the expert shouldn’t forget to place another strip above the specimen. Later, the pressure needs to be applied relentlessly until the concrete specimen starts cracking along the diameter. At this instance, the expert has to record the reading which is nothing but the breaking load. He then has to use a formula for calculating the tensile strength of the specimen. Typically, the tensile strength may lie between 1/8 and 1/12 of the compressive strength. If you’re using mini concrete Brisbane, then you should be mindful of the time for which the specimen is exposed to water.

2. Flexure Test

The flexure test is yet another test that can help you determine the tensile strength of concrete. Before proceeding with the following steps, first pour fresh concrete into the moulds to create samples. Rather than coming up with just one sample, create three specimens for the test. Keep the hardened concrete in the water at a temperature between 24 and 30 degrees Celsius for two days.

After the specimen undergoes curing, it has to be placed carefully between the loading points. After some time, a load equivalent to 2% to 6% of the ultimate load has to be applied steadily. Mesh reinforcement Brisbane is essential for concrete slabs at the construction site.

Towards the end, as soon as you calculate the loading rate, find out the modulus of rupture. This figure is nothing but the extent at which the concrete cracks when it is subjected to continuous load or pressure. Post test, set the testing machine to a configuration for cylinder testing. Also ensure you discard the specimen and clean the testing machine thoroughly.

Once you have decided on what type of concrete you need, you can find suitable tools online. If you are concerned about completing the construction project, you should contact firms dealing in concrete delivery Brisbane  such as Reocrete Brisbane.

Steps to Consider when Reinforcing Concrete Slabs with Wire Mesh

Whenever there’s a need to make concrete slabs, it’s necessary to use a welded wire mesh. While this wire mesh is an alternative to reinforced steel rods, it prevents cracking of concrete in the future. According to concrete suppliers Brisbane, it’s better to reinforce wire mesh so that it settles at an appropriate height once it has been poured. So, if you are unaware of how to reinforce concrete slabs, then read ahead to learn more about the steps.

Step 1

As soon as you start, you have to carefully place the slab runners for supporting the wire mesh. The slab runners play a better role in elevated concrete pours. With every runner being 4 feet long, you should take care of placing the runners. Ideally, you have to maintain a distance of 3 ½ feet between two consecutive runners.

Step 2

Now, you have to place the first sheet of mesh just above the slab runners. In case it’s a slab on grade, then you can place the mesh on the ground. You should start off from the corner so that you can maintain sufficient clearance. Do keep in mind that the metal should not be in contact with the edge of the poured concrete. This would certainly help because it actually prevents the chances of the exterior getting affected due to rust. If quality is the prime concern, then you can try out premix concrete Brisbane.

Step 3

Now, you need to place the next sheet right above the first sheet of wire mesh. At this instance, you have to place the wire mesh one and a half squares away, letting every sheet to overlap the other 1 ½ squares; it’s essential to apply some pressure on the second sheet and force it down. You should make sure that the second sheet is perfectly resting on the slab runners. In order to be accurate with the overlapping technique, you might have to adjust the second sheet a bit later.

Step 4

Soon after placing the wire mesh, you have to tie the sheets all at once. With the help of Linesman pliers, you have to tie the corners and tie the centre of the overlapping sheets as well. Way ahead, you need to be sure that the ties have brought two sheets closer. As you proceed with placing the wire mesh, continue tying it till the slab has been covered completely. If you wish to save money, then you could get in touch with suppliers and check out concrete prices Brisbane.

Step 5

Subsequently, you have to lift up the entire mesh at a suitable height from the slab. In case you have placed the slab runners on the ground, then you don’t have to follow this step. Moreover, you have to place 2×2 concrete bricks just beneath the wire mesh. As you work towards supporting the mesh, you should place the bricks at least at a distance of 4 feet.

Finally, before reinforcing the concrete slab, you should check whether the mesh is designed for construction projects. You should also check for the dimensions and size depending on the area that needs to be reinforced. If you don’t know what to purchase, then feel free to research online. This would give you a fair idea about the size along with the price. While you procure supreme quality steel reinforcing mesh Brisbane from the market, just be sure that the material is galvanised.

Three Major Benefits of a Reinforced Concrete Slab that you Cannot Overlook

Concrete has got excellent compressive strength. Leading experts at concrete suppliers Brisbane say that concrete slabs must be reinforced with either rebar or re-mesh. It is worth noting that concrete’s tensile strength is not that high compared to its compressive strength. It is extremely tough to crush concrete. However, it is not difficult to pull it apart. Concrete slabs offer stunning thermal comfort and long a life to any structure. Flooring that includes bars and mesh will go a long way in boosting bonding with concrete. The concrete reinforcing mesh can also bring down concrete cracking due to shrinkage.

Here are some of the major benefits of a concrete slab:

1. High compressive strength:

The presence of sand and crushed rock in concrete offers compressive power. The availability of sand and rock in concrete prove useful in supporting a huge amount of weight. It is worth noting that harder the rock and higher the rock in the mix ratio, the more powerful the compressive strength of concrete is. The usual mix ratio is four to one i.e. four portions of crushed rock and two portions of sand and one portion of cement. You may adjust the ratio to provide a higher compressive power. You can obtain high-quality concrete and other components from leading steel suppliers Brisbane.

2. Tensile strength:

Reinforced concrete slabs have become significant because it is not the compressive integrity of a slab that may fail first. It is the tensile resistance that may give way. The slabs tend to break and crack due to the poor tensile resistance of concrete. The availability of rocks and sand in concrete provides strong compressive power. All the tensile power of concrete is generated from cement. The tensile strength can be described as material’s adherence strength. However, just like glue, cement can be pulled apart; bending and torsion play the role of testing the tensile power of concrete. You must carefully obtain top quality reinforcing mesh Brisbane from renowned suppliers.

3. Durability:

A concrete slab offers a high life span with effective reinforcement. It implies that concrete must be compacted so that no gap or porous areas are left within the slab. It can also help in bringing down the risk of concrete rupturing. You can also help in enhancing the concrete slab life with effective foundation preparation and by adding an adequate amount of water. Be careful about the quantity of water as an excess amount may cause cracking and weakening of the entire slab. Take good care of the concrete installation and follow the timelines so that it achieves desired strength before any load is placed.

Conclusion:

Reinforced concrete offers several benefits. You should purchase premix concrete Brisbane from leading suppliers who promise quality. Top-quality concrete can set, harden, and secure its power at regular room temperature. The reason behind this is that cement has emerged as a low temperature bonded inorganic material.

How to Minimise Plastic Shrinkage Cracking

Plastic shrinkage cracking occurs as a result of how fast the concrete surface dries in comparison to the rest of the concrete. According to concrete suppliers in Brisbane, plastic shrinkage tends to form when the concrete is still plastic. Plastic shrinkage may take place any time throughout the year whether the weather is cold, hot, windy, or low humid. It is worth noting that plastic shrinkage cracks take place in an arbitrary manner or they will be parallel to each other. Most often these cracks are straight and their length may vary between 2 m to 25mm. They will hardly occur around the edges of a slab. The cracks create a weakness in the concrete and possess the capacity of further widening as a result of subsequent thermal movement.

6 Important Tips to Minimise Plastic Shrinkage Cracking

Described below are some important tips to minimise plastic shrinkage cracking in concrete:

1. You should erect temporary windbreaks:

When the wind blows at a higher velocity, it may significantly impact the water evaporation rate from the concrete being placed. It will likely cause plastic shrinkage cracking of the concrete. In order to prevent this, you may opt for erecting temporary windbreaks. This will help in reducing wind speed at the surface of the concrete.

2. Sunshades:

When you are constructing concrete slabs, the option of providing sunshades over the concrete slabs will prove helpful. It will aid in controlling and bringing down the surface temperature of the slab.

3. Effective placement timing:

During extreme hot weather conditions, it is not ideal to erect the concrete during the afternoon. If you do so it may cause plastic shrinkage cracks as a result of water loss. Therefore, it is ideal to schedule concrete placement in the morning or evening time, this just allows you more control over the concrete temperature.

4. Opt for fog sprays:

During scalding hot weather conditions, the wind tends to be extremely hot and unbearable. You should opt for fog sprays to spray fog in the hot air on the concrete surface as it helps to reduce the evaporation rate from the concrete surface. You should spray fog towards the opposite direction the wind is blowing.

5. Try dampening subgrade:

When the construction of concrete pavement is underway during hot weather conditions, you should dampen the subgrade as it is responsible for water absorption from the concrete, however, it is important to note that subgrade should never be excessively damp.  Steel suppliers in Brisbane will help you minimise plastic shrinkage cracking.

6. Use evaporation retarder:

As we are aware that surfaces may dry earlier than anticipated when the evaporation rate is higher than the bleeding rate. You can consider spraying an evaporation retarder like aliphatic alcohol on the concrete surface. These types of products help in forming a fill on the surface that reduces the evaporation rate of water. It also provides time for all the bleed water to move towards the surface. In extremely hot weather conditions, you may have to consider re-application of evaporation retarder.

Conclusion:

The above ways will help you minimise plastic shrinkage cracking. You may get in touch with reinforcing mesh in Brisbane to tackle the situation effectively. Do not forget to avail adequate manpower, devices, and supplies to ensure that concrete can be placed and finished instantly.

What is Plastic Shrinkage Cracking?

Plastic shrinkage cracking refers to the cracks formed when concrete has not yet set. It occurs when the concrete is in the form of plastic only. The main cause behind crack formation is the rapid drying process. Cracks can be seen the next day after the finishing operations. Plastic shrinkage cracks can form randomly or can be roughly parallel to each other. Concrete Brisbane gets weak due to these cracks and therefore expand.

What Causes Plastic Shrinkage Cracks?

The basic reason behind the occurrence of cracks is the higher rate of evaporation of moisture from the surface. When the evaporation rate exceeds the moisture supplied to the concrete, cracks are formed. The concrete surface dries out because of the lack of moisture on the surface and hence it cracks.

Water is lost in the following two ways:

  1. Drying from the top: During the placement process, moisture seems to evaporate from the top surface of the concrete, which is also known as bleeding.
  2. Drying from the base: Water can get absorbed in the ground below the concrete slab. This increases the risk of cracking and also the settlement of concrete and mesh reinforcement Brisbane.

There are various environmental factors that affect the rate of evaporation from the surface of concrete, such as wind speed, temperature, and humidity. A combination of all these factors leads to cracking even in cold weather conditions. Also, the concrete mixtures which have a reduced rate of bleeding are prone to plastic shrinkage cracking. Any factor that contributes to a delay in the setting process, leads to cracking.

How to Control Plastic Shrinkage Cracking?

Mentioned below are the tips that will help you in minimising plastic shrinkage cracking in your concrete:

  • Dampen the surface of concrete frequently.
  • During hot weather, mix water with crushed ice or use chilled water.
  • Use windbreaks to reduce the velocity of wind that is coming on the surface of the concrete.
  • Use product substitutes that reduce the rate of evaporation from the surface.
  • Start the curing regime immediately after finishing.
  • Use synthetic or steel fibers to prevent cracking.
  • Accelerate the setting time of concrete.
  • Use fog sprays in dry periods to discharge a fine mist into the air. Fog sprays reduce the rate of evaporation from the surface of mini concrete Brisbane and should be used until curing is applied to the concrete.
  • Cover the concrete with moisture-retaining coverings like polyethylene or building paper sheets.

Reocrete is the leading supplier of concrete and steel reinforcing mesh in Brisbane. We deliver the right grade and consistency of concrete to your worksite at the exact time and day you need. We understand how much of a difference just a 30-minute delay in the compaction of concrete can cause. So, we practice what we preach and deliver exactly what you need!

6 Different Types of Cracks in Concrete

Concrete is easily one of the strongest and most reliable construction materials. From temperature changes and structural errors to tree roots and reinforcing mesh Brisbane, many things lead to cracks in concrete. Unlike the common perception, not all concrete cracks are the same. In fact, identifying the correct type can actually help you in properly correcting the cracks.

Let’s take a look at the six most common types of concrete cracks you might encounter:

1. Plastic Shrinkage Crack

Before the concrete hardens, it is considered plastic and contains a significant amount of water. Sometimes puddles of water, upon drying, leave behind voids within the slab. Such voids make the structure of the slab prone to cracks when subject to pressure. Unless prominently visible, plastic shrinkage cracks pose no threat to the structure of the slabs.

2. Expansion Crack

When subject to heat, concrete slabs tend to expand outwards. Lack of space to expand causes slabs to develop cracks. However, expansion cracks are mostly dealt with during the planning and concrete delivery Brisbane stage of the structure. Expansion joints are inserted between slabs that can absorb pressure from expansion and thus pre-empt and avoid cracks.

3. Heaving Crack

Another crack that occurs due to temperature are heaving cracks. Heaving cracks develop due to being exposed to extreme cold weather, which causes the slab to condense. When the temperature returns to normal, the slab also expands back to its normal shape. However, this change in shape often leads to the development of heaving cracks.

4. Settling Cracks

The structural weakness of the underlying ground can lead to settling cracks. For instance, when a large tree is removed, its roots decay and leave large voids behind which soften the ground. A weak ground gives poor support to the concrete slab above and the steel bar Brisbane surrounding it, causing settling cracks.

5. Cracks due to overloading

Premix concrete Brisbane comes with their own strength (measured in PSI or pounds per square inch), which indicates the maximum pressure they can take before being crushed. However, overloading of slabs occurs quite often in residential areas – this is not what actually causes the cracks. In cases where the underlying ground has become soft (like after heavy rain), it might enable a section of the slab to be pushed downwards. Heavy vehicle parking spots are most likely to see such cracks.

6. Premature Drying

When a concrete slab (or its top layer, to be specific) loses moisture quickly, it can lead to cracks. Crazing cracks appear when the top layer of the slab quickly loses moisture naturally, resembling a spider-web. Crusting cracks appear during the stamping process when the top layer is dried for embedding patterns. Both these types might look unappealing, but they are largely harmless for the structural strength of the slab.

As you saw, different causes lead to different types of concrete cracks. Understanding the specific types allows us to identify the root cause behind these cracks and take appropriate steps.

Do 3D Printed Houses Require Reinforced Concrete?

3D printing is used everywhere from the fashion industry to the medical industry, and houses are not left behind. Revolutionary 3D printed tiny-homes are now a reality. Large scale 3D printing is now being used in bigger construction projects to build entire mini concrete Brisbane houses, buildings, and a lot more. 3D printing is certainly showing its benefits and amazing patterns on the walls of urban houses, it has become an asset for construction projects.

3D Printing for Construction

Surely the 3D printing technique has become an inspiration and a new tool for civil engineers. New technologies are being used nowadays, for example- a 3D printed concrete house can be printed directly in one go, or in different parts to assemble later. New materials are also being used in order to create such amazing construction projects. New technologies like robotic arms are being used which are capable to print entire structure very fast.

Use of Reinforced Concrete for 3D Printed Houses

In conventional reinforced cement concrete, the rebar used is of a diameter ranging between 6mm-35mm, which gets difficult to incorporate into the printing process. If any kind of reinforcement is to be used with 3D printing, then the rebar diameter should be kept very small to allow for manipulation later.

What is Ferrocement?

Ferrocement is a form of reinforced concrete that is made up of densely spaced layers of mesh reinforcement Brisbane or steel rods of very small diameter enclosed in a mortar to form thin sections. Ferrocement is being used widely in the construction industry due to its benefits like low skilled labor requirements, fabricated into any desired shape, long life, ease of construction, and less weight.

Benefits of 3D Printed Houses

  • 3D printing is not only used to print homes, but it can also be used in a wide variety of minor construction projects.
  • The precision of printers used in 3D printing helps in saving resources and energy. Also, immediate houses can be built in the of a disaster.
  • A 3D printed house costs less, however, the cost majorly depends on the complexity, size, and timing. A 215 square ft. house requires approximately 10 days to build.

You can get the best quality concrete from Reocrete concrete delivery in Brisbane. We use a success-proven process for planning, tracking, and managing the biggest construction projects. Reocrete believe in saving you, time and money. Contact us Today!

Rebar Tie Positioning Within Your Concrete Foundation

Rebars or reinforcement bars are extremely necessary for the structural stability of any construction project, as it ensures the building is crack resistant and strong. Concrete however, lacks tension strength and can crack easily. The presence of the rebars reinforce the concrete and helps to hold it in the compressed state. Reinforcing mesh Brisbane is found in a multitude of constructions.

Rebars should be placed in concrete that measures at least five to six inches in depth. They have to be placed either at the centre or a little above the slab’s centre. This is why the thickness and quality of a concrete slab matters. The steel rebar also has to be placed in the correct location for maximum structural benefit. Placing it in the wrong place can cause major structural failures.

Things to Keep in Mind When Placing a Rebar Tie

To begin with, the rebars should be tied properly into a meshed structure before placing the same on the concrete. There are some important points that have to be remembered while tying the rebars.

  • The rebar frame has to be placed correctly on the slab, not too high or too low. If it is placed incorrectly then the load-bearing capability will suffer hugely and the structure can develop cracks.
  • Professional builders are aware of the basic laws regarding placement of a rebar tie. They will never pour premix concrete in Brisbane on top of a rebar structure or place a rebar structure on fresh concrete.
  • The rebars have to be reinforced with the help of steel wires at the main points. This helps in maintaining balance and strength irrespective of the weight of the metal in the structure.
  • Professional builders will always use metal wires for strengthening the bars rather than lower quality alternatives.
  • The rebars should be secured properly to avoid displacement. The tie wires for steel bar in Brisbane have to be secured at the right points. They should be wrapped in four-pound coils. Ideally, annealed wire of 16 gauges or more should be used. In case of more heavy reinforcement wire, you can even use 14 gauges for holding the rebar in the right position.
  • If you happen to be using rebar that has been coated with epoxy, then plastic PVC ties can also be utilised. Some builders use Snap-on ties that can be snapped together using ones hands. This method is less expensive and quite easy.
  • Ideally, every intersection of the rebar has to be tied for maximum support. The ties do not actually make the structure strong. They prevent the rebars from getting displaced when the concrete is being poured.
  • The tie wires should be placed at the right depth from the surface so that the rebar does not rust. It also prevents the concrete from eroding.

Conclusion:

Rebar tie positioning becomes important when the instructions and blueprints of the construction are not being followed to the ‘t’. If the builder is a true professional and follows the specified number of bars in the design blueprint then there is nothing to worry about regarding the positioning of the rebars. And of course, a specialised builder will purchase the right number of quality bars and from steel suppliers Brisbane for the best possible results.

A Step-by-Step Guide to Polish Concrete

You need to adopt some vital measures to polish concrete correctly. In order to achieve perfection in your job of polishing concrete, you must go through a step by step procedure. This will help to give you the desired results. Along with this, you may also need proper tools and equipment to execute the task. For effective polishing, you should have machines with abrasives that will assist in grinding the concrete surface to a smooth level. And, you may need to move from rougher grit to smooth grit abrasives – this will produce a stunning finish that looks glossy. To the opinion of concrete suppliers Brisbane, you may polish concrete either with dry or wet techniques. The wet method is preferred more as it has emerged easy, fast, and environmentally-friendly.

Given below are some crucial steps to polish concrete:

1. Prepare the area that you need to polish:

Before you start work on the concrete floor, the area you need to polish needs some preparation. The time of your preparation will directly depend on the condition of the surface. You need to sweep and mop the area to eliminate all the dirt and dust on it. Now remove all the coatings or sealers that you may have applied recently to the surface. Make sure that you have repaired all the cracks or blemishes on the surface.

2. Use a rough grit abrasive disc:

After you have cleaned and repaired the surface, you need to start the process of polishing. You may require several diamond abrasive disc types and a concrete grinder at this stage. Polish the surface with a rough grit abrasive disc. This helps in eliminating all the stains available on the surface along with rough areas. You must use the correct technique when polishing the surface to get the desired results. The proper technique may include moving the grinder in circular motions. You may also begin from a specific section of the surface and systematically and gently to the areas. You ought to cover the entire surface without missing even a single area. You may seek assistance from leading reinforcing mesh Brisbane in getting the job done.

3. Use smooth grit abrasive disc:

After using the rough grit abrasive, you need to use the smooth grit abrasive disc. The biggest advantage of this disc is that it will offer your surface a shiny and sleek look. It is often linked with polished concrete.

4. Use extra smooth grit abrasive disc:

Now in the final step, you need to use the grinder along with an extra smooth grit abrasive disc. It will help in grinding the surface. The purpose of the fourth step is to ensure that all the stains and marks have been eliminated from the surface. And, it gives you a smooth and sleek surface. The concrete prices Brisbane has been in the competitive range and will not disrupt your budget.

5. Apply surface polish coating:

Soon after the polishing of the surface is finalised, you must protect it from any damages or harms. You may add a coat of concrete surface polish that will offer great protection to the surface.

Conclusion:

The above steps will prove handy in protecting your surface from any possible damage. The five steps guide will allow you to execute the job independently without obtaining any help from an expert. It will help you give your surface the required touch to make it look smooth and sleek. Several leading steel suppliers Brisbane offers their crucial inputs in polishing the concrete surface with correct technique and tools.