Know The Factors Which Impact Your Concrete Mix Design

concrete-mix-design

One of the primary reasons why the demand for reputed concrete suppliers is always quite high is because concrete is one of the most preferred man-made construction materials. It offers the perfect blend of affordability and durability. Just make sure that the material is prepared by mixing cement, aggregates and water in the right quantity. Once the mixture is poured in forms, they cure and become hard like a rock. The workability, strength and durability of concrete are largely dependent on how the mixture is prepared and the method of compaction. But before you start looking for a concrete supplier, know the common concrete mix designs and the factors which impact the design mix of concrete.

concrete mix design

2 Types Of Concrete Mix Design

  • Nominal Mix Concrete

It is a rough method of concrete mix design which works on the principle of ratio or volume. Cement, sand and aggregates are measured before mixing instead of mixing them randomly. A unique feature of nominal mix concrete design is that they don’t require any lab testing. They are used in various parts of the world for ordinary concrete construction where the concrete grade requirement is less than M15. The M20 design mix is used for higher grades. This concrete mix design works on the principle of volumetric batching.

  • Design Mix Concrete

Design mix concrete is more popular than nominal mix concrete as it works on the principles of mix design. Builders choose this variety when they need concrete of desired quality for their construction project. They are even more affordable than the one stated above. Reputed concrete suppliers like Cobra Concrete Ltd. always conduct laboratory testing of the constituents before mixing them.

3 Factors Which Impact The Design Mix Of Concrete

  • Workability Of Concrete

If you are looking for proper placement and compaction of concrete, a few factors you should consider are the spacing and quality of reinforcement, shape and size of the section you want to concrete and how you are transporting and placing the concrete. Quality concrete offers satisfactory placement and compaction of concrete and minimum possible workability. Insufficient workability will have a negative impact on the durability, strength and surface finish of a concrete structure.

design mix concrete
  • Durability Of Concrete

You can stay assured that the concrete you are using is durable if it is resistance to deterioration even in an aggressive environment. Concrete suppliers in Surrey achieve the desired durability by minimising the cement content and grade of concrete and maximising the water cement ratio. Sometimes, chemical and mineral admixtures are also added to the concrete mix to enhance their durability.

  • Grading Of Aggregates

If you are using both coarse and fine aggregates when preparing the concrete mix, ensure proper grading of combined aggregates. The proportion in which they are mixed will impact the material’s strength and workability. Your concrete mix will be leaner if the grading is coarser.

Since you now know the common concrete mix designs and the factors which impact its design, it’s time you start looking for a reputed concrete supplier.

Concreting Tips For Construction Workers During Summer

concreting-tips-hot-weather

There are a few people who think using concrete during summer is as easy as using it during the rest of the year.  High summer temperatures, low humidity, direct sunlight, high concrete temperatures and even modest wind velocity can cause concrete surface cracking (plastic shrinkage cracks).

concreting tips in hot weather

Concrete preparation, placement and curing become a problem when the weather becomes too hot. Cement starts hydrating rapidly when the temperature increases, water evaporates quickly and construction workers often get confused about how much water they should mix to prepare concrete. The objective is to prevent cracks from developing in the concrete structure later. If you want to reap all the benefits offered by high-quality concrete in Sidcup, take all the precautions necessary during hot weather concreting.

3 Effects Of Hot Weather Concreting

  • To maintain the workability of concrete, you have to mix more water when preparing it. As a result, the strength of the material reduces drastically.
  • Plastic shrinkage cracks might develop in the structure before or after the material has become hard. It generally occurs due to rapid evaporation of water when the temperature becomes too hot. Cracks might also develop in the structure due to increased drying shrinkage.
  • Water has evaporated more rapidly than they should during the curing period. The easiest way to prevent the issue is by ensuring that the temperature remains uniform throughout the curing process.
high-quality-concrete

7 Tips To Minimise The Impact Of Hot Weather Concreting

  • Avoid pouring or using concrete between 11 am to 4 pm as the temperature is at its highest between these times.
  • Create a shed in your construction site to store sand, cement and stone aggregates.
  • Keep stone aggregates cold by sprinkling water over them at fixed intervals.
  • Sprinkle cold water on reinforcements, forms and sub-grade just before placing the concrete.
  • Try to finish the concrete placement process quickly if you want to minimise the impact of hot weather concreting.
  • Using concrete after a long time you have prepared them will decrease the material’s workability. You have to mix more water to deal with the situation.
  • Start moist curing concrete once it attains the required degree of hardening.

These being said, it’s time you follow the tips stated above and choose a reputed concrete supplier if you want to minimise the impact of hot weather concreting. 

4 Reasons behind the Failure of Concrete and How to Avoid Such a Situation

concrete-failure

Concrete is one of the most sought after human-made building material. It is a staple element for construction projects for its excessive strength and heat-proof elements. These are the factors that have helped it to gain immense popularity. Concrete, in general, is very durable, but still, it is not free from a few specific weaknesses. Unless some measures are taken, then there are chances that the concrete might fail to hold on to its sustainability.  Here is an attempt to explore the four most important reasons why concrete ought to fail and the ways to prevent such an occurrence as you are availing concrete in Orpington.

concrete-failure

Four ways concrete might fail and how to eliminate the chances

Inappropriate raw materials resulting in low-quality concrete

There are many instances when the raw materials can be solely blamed for the failure of the concrete. If the selection of raw materials will be wrong, then the quality of the concrete will hamper to a great extent. The ratio of the raw materials should be determined carefully as the quality of mixed concrete mainly depends on it. If the ratio won’t be perfect, then the concrete will tend to break at a faster rate and won’t have the required strength. To avoid such a consequence, be sure about the type and proportion of the raw materials. It will help if you put in adequate research before deciding on getting concrete in Orpington.

Poor finishing during application leading to trapped air in the concrete

It is a common problem encountered while applying the concrete. Due to poor finishing, some amount of water and air bubbles tend to get trapped within the concrete particles. This can cause exponential damage to the concrete structure by reducing its strength and making it weaker. Adequate care must be used to keep the air content around 3% and to ensure that the concrete is not suffering a premature finishing. It is also essential to properly maintain the manufacturing conditions to prevent the air from getting trapped within.

Cracks in concrete due to the reaction between alkali and silica

There are cases when the aggregates contain silica and alkali. As they are exposed to humid condition, a sort of gel formation occurs, and then the concrete tends to crack. These result in crumbling of the concrete structure. To prevent this, one should be careful about not letting the silica content in the aggregate gets exposed to humid conditions.

Choosing the wrong type of concrete overloading concrete exceeding the point of failure

Concrete comes in different varieties, and each of them bears a different kind of strength. Based on that the type is chosen. For instance, if the structure needs to support considerable weight, then reinforced concrete needs to be used. Hence, if the wrong variety is determined by mistake or to cut the cost, then there are chances that structure will fail when heavy loads are exerted. To avoid such an instance, choose the right type and do not indulge in overloading the structure beyond the specified limit.  The best option to have the highest quality concrete would be choosing a reputed concrete supplier. Cobra Concrete is a trusted name in the specific domain. Count on them to have your structure made of concrete in Orpington strong and sturdy always.

Planning To Construct Concrete Buildings? Know The 7 Steps Involved

concrete-buildings-bexley

One of the construction materials which people have been using for years is concrete. Every concrete building is durable and requires minimal maintenance. Recently, construction workers have started using innovative concrete technologies which have made laying and pouring of concrete easy. If you are willing to use the conventional method of concrete construction, get in touch with an experienced supplier of concrete. A majority of them have years of industry presence and know the various ways you have to follow when preparing the construction site, build the framework, place reinforcement, mix, pour, finish and cure concrete.

construct concrete buildings Bexley

Follow The Steps Below And Construct Concrete Buildings In Bexley

•    Estimate The Materials You Need

It is necessary to mix the concrete ingredients in correct proportion if you want the material to be of high quality. The batching process will help in carrying out the right measurement of the concrete ingredients. Approach a renowned supplier of concrete in Bexley as the proportion and quantity of cement, water and aggregates are important.

•   Prepare The Site

A very vital aspect of pouring concrete is site preparation. It is the responsibility of the construction workers to ensure that concrete is poured on a compacted and well-drained soil. The subsurface should be properly prepared and it will help in minimising potential cracks.

•   Build The Formwork

The importance of formwork in construction can never be neglected as they are responsible for supporting structures. Moulds are also created inside which concrete is poured. Few materials generally used to build the framework are steel, wood and aluminium.

•   Place Reinforcement

You can protect a concrete structure from displacement by placing the reinforcement accurately and supporting it properly before placing the concrete. Construction workers place reinforcement after considering the number of bars, bends, positions and bar lengths. This step will assure that the steel is bonding well with the concrete.

•   Mix The Concrete

How you mix the concrete ingredients will impact the quality of the concrete, both in its hardened and fresh state. It is necessary to mix the material well. It should be informed in colour. You can achieve proper consistency if the material is designed the right way.

•   Pour The Concrete

It is necessary to pour the concrete within the initial set time if you don’t want to deteriorate the quality of the concrete structure. Two common methods through which concrete is poured are pumping and manual transportation. Sometimes, vibrators are used to compact the poured concrete.

•   Finish The Concrete

How you finish a concrete structure is very important as it renders the building a smooth finish. Hire experienced contractors as they know the right method screeds and trowels that should be used to level the surface after the concrete is poured.

These being said, it’s time to follow the steps below above and constructing concrete buildings will become easier.

Using Concrete In Cold Weather? Few Things You Should Avoid

concrete-in-cold-weather

Concrete is subjected to different curing conditions as the temperature fluctuates which makes the material gain sporadic strength. Contractors willing to protect fresh concrete have to take a bit of preparation before the climate changes. They should know the right equipment to be used at the job site like blankets and tarps. These help in preventing unsafe concrete development and avoid unnecessary delays.

concrete in cold weather

Working with concrete becomes a complicated task in Croydon as the outdoor temperature goes below 40 degrees F and the air temperature goes below 50 degrees F. Such being the situation, contractors should follow a few do’s and don’ts when using concrete. Negligence to do so can lead to structural problems and delay your project.

5 Mistakes To Avoid When Using Concrete In Cold Weather

  • Pouring The Material On Frozen Ground

Make sure you don’t pour concrete on to frozen ground even if you are in a hurry to complete your construction project. The effectiveness of the concrete curing conditions is largely dependent on how the concrete is poured and slabs are placed. It will take less time for the concrete near the surface to cure than the one close to the ground. The chances of the concrete cracking and structure disaster increases as the material can’t develop strength properly.

  • Sealing The Material When The Weather Is Cold

The primary objective of using concrete sealers is to make the material more resistant to external element and weather exposure. Construction workers using concrete in cold weather should use a sealer which has been specially designed for extreme weather conditions. Even if you are in a hurry, don’t seal concrete when the temperature is below 10oC.

  • Misjudging Daylight

The amount of daylight experienced by the people in Croydon becomes low during the colder months. Instead of running behind schedules, try to use your time wisely. If possible, pour and cure concrete during daytime as the temperature is warmer when there is an abundance of light.

  • Allowing The Material To Freeze

Concrete in Croydon can cure properly only if it is kept in warm temperatures (not exceeding 10oC). If the temperature is below -4oC, fresh concrete can freeze really quick. It is the responsibility of the contractor to keep fresh concrete warm until its compressive strength measurement becomes appropriate. A suitable concrete temperature and maturity meter like SmartRock can be used to do this task.

  • Using Cold Tools And Equipment

The temperature of the tools and equipment you are using to pour and cure concrete should also be as warm as the raw material. The composition and temperature can change if the tools you are using are too cold. This will have a negative impact on the strength of the concrete slab. Avoid the mistakes stated above when using concrete in cold weather and the concrete structure will be durable and beautiful.

Choose the Perfect Mixing For Your Construction Project

concrete mixing methods surrey

During the old times, when readymade products were still a far-fetched dream, the concrete mix was created with a manually done blend of cement, sand, lime and water. But times have changed, and pre-blended concrete mixes are readily available anytime. But the trick of mixing the right amount of water still lies with the builder.

concrete mixing methods

Understanding the three most important methods

Hand Mixing

The purpose of hand mixing is true to its moniker. It merely involves break the dry material blend into a big enough container, pour the adequate amount of water, and then mix by hand. A stirring tool or jiffy mixer can be used for the blending process. But it is not favoured for large-end constructions for apparent reasons. It is a slow and inconvenient process and is always in a risk of miscalculating the wet-to-dry proportion, resulting in a weaker concoction than expected.

Batch Mixing

Batch mixing is commonly seen in medium-scale constructions for blending of concrete in Surrey. The process is to make several batches of concrete mix in a day’s work by churning the dry blend and water together in a mechanised mixer basin. The amount of mix blended in one turn depends on the size of the mixer. Most commercial ones can make around 8-12 cubic feet of material at once. But it poses a limitation that is similar to hand mixing – the possibility of inadequate or excess amount of water. The measurement of water is done manually, and hence the possibility of a mismatch between two batches of the mix is very much there.

Continuous Mixing

This newer and cutting-edge option involves a mixer machine that takes care of everything, making the element of human error out of the equation. The builder or operator has to pour out the dry material into the hopper and switch on the necessary buttons. A dosing shaft automatically pushes the dry blend into the mixer and then adds pressurised water. The amount of water inflow can be adjusted from outside, which assures proportion accuracy in this method of mixing. It allows the mixture to be consistent, and once it is done, it can be transported to any location required.

Which one to choose?

The decision lies entirely on the nature of the construction. The factors that should determine your choice are:

  • Size of building: Batch mixers serves well for small to medium scale projects, while continuous mixtures are ideal for large scale projects.
  • Portability: Hand mixing is the most portable. Some batch and continuous mixers are qualified for transportation as well, though it requires logistics.
  • Power supply: Batch mixers can operate on a standard plug pin, but continuous mixers need at least a 23-Volt outlet to function. Cobra Concrete is a family-owned supplier of concrete solutions that are sustainable, cost-effective and energy-efficient. With an industry experience of over two decades, they are among the top companies that come to mind when you think of concrete solutions in Surrey.

4 Reasons Why Concrete Is The Most Preferred Building Material

concrete-building-material

Choosing the right building material for your construction project is indeed a daunting task with so many options available in the market. If you want to make a wise investment by choosing the right building material, consider its cost, safety, durability and sustainability. You should pay equal importance to all these factors.

Concrete Building Material

Though steel is durable and robust, they are a bit expensive and can increase the cost of your construction project drastically. Wood though being cheap, can make a structure unsafe and less durable. One of the building materials with high demand in the construction industry is concrete. It is energy-efficient, affordable, durable and safe. All these help builders complete a project quickly and without exceeding their budget.

Few Reasons Why Concrete Is The Ideal Building Material

  • Easy Maintenance

Concrete structures don’t require much maintenance and are given more preference than other building materials. The quality of wood and steel deteriorates over time and you have to maintain them to get optimal performance. Just make sure you repair the small cracks before it’s too late. Concrete structures require very little or no maintenance which help you save money in the long run.

  • Wind And Water Resistance

Though wood was widely used by construction workers earlier, they are not resistant to wind and water which had a negative impact on their durability. Concrete, on the other hand, is completely resistant to wind and water which makes it a safe building material. You don’t have to worry about the structure breaking during a storm or mould damages in the presence of excess water.

  • Durability

The durability offered by quality concrete in Orpington is one of the primary reasons behind its high demand. Every structure made using concrete is expected to last for years. The level of durability is unparalleled when compared with other building materials. They don’t decay, rot or rust which enhances their durability even further. You can make a concrete building and make it last for years without breaking the bank.

  • Fire Resistance

Concrete structures are considered to be fireproof as the material doesn’t absorb heat. A fire-proof building made using cement is given more preferences than wooden houses. The latter is quite vulnerable to fire damages. Concrete walls and floors act as a fire shield and keep flame outside the building. This helps in keeping the goods and furniture in your room protected. Since you now know why concrete is a more preferred option when compared with other building materials, it’s time you start looking for a reputed concrete supplier and reap all the benefits stated above.

Pros And Cons Of Using Ready Mix Concrete

pros-cons-of-ready-mix-concrete

Quality concrete with the right consistency is crucial for any building you are looking to construct. Today, the concept of ready mix concrete has emerged as a solution for your construction hassles. If you are looking to source reliable concrete in Croydon for your building needs, you can place your faith in Cobra Concrete. We are a leading supplier of ready mix concrete.

Pros Cons Of Ready Mix Concrete

What is Ready Mix Concrete?

Instead of churning sand and stone chips in a cement mixer at your construction site, a ready mix concrete is produced in a dedicated factory space in a batching plant. It is produced according to your building specifications and then transported to your building site using transit mixers for further use. There are three major types of ready mix concrete:

  1. Transit mix concrete
  2. Shrink mix concrete
  3. Central mix concrete

Pros of Using Ready Mix Concrete

If you are looking for ready mix concrete in Croydon for your building project, you must consider the pros and cons of the material. Using ready mix concrete comes with a lot of advantages. Some of them are as follows:

  • Speedy construction: Since the concrete mixture is manufactured in a ready-to-use state, it considerably speeds up the construction process. You do not need to dedicate any time to mix raw materials and churn them to produce concrete. Instead, timely delivery of ready mix concrete from Cobra Concrete and your construction project will be underway in the blink of an eye.
  • Economical: Outsourcing of ready mix concrete cuts down the costs of your project significantly. You do not have to purchase any machinery or employ labour for the production of cement. Instead, you can dedicate your time, efforts and money solely on the construction details and let us deal with the hassle of producing quality concrete for your building needs.
  • Consistency: Producing batches of cement on-site often cause consistency issues due to a shortage of material or time. By purchasing ready mix concrete from Cobra Concrete, you can rest assured that you get reliable and consistent quality of cement. Thereby, you can get optimum results.

Cons of Using Ready Mix Concrete

  • Transportation: Ready-mix concrete has to be transported to the site of construction. This transit may take some time if the location of cement production and the building venue are located far apart. Further, this time lag can cause the ready mix to set before it can be used.  Efficient retarders may be added to the mix to delay setting to solve this problem.
  • Inventory: It is crucial to have a dedicated facility at your construction site to store the concrete from Croydon. Since you are likely to purchase ready mix concrete in bulk to provide for your entire project, you have to be judicious in storing the material properly. Ordering in batches can also be helpful in the case of long-term projects.

Cobra Concrete is the notable concrete supplier putting particular emphasis on producing and delivering quality ready mix concrete. They aim to provide the best results for your projects, and their biggest goal is to make customers happy with an exquisite range of products and services.

Working With Concrete? 5 Tips To Ensure Your Safety

concrete-safety-tips

The construction industry is indeed a bit hazardous, especially for construction workers. It is mandatory for them to acknowledge their own set of safety concerns. All the industry set standards and regulations should be put in place to ensure the safety of the professionals working on job sites. If you are working with concrete, not only should you approach renowned concrete suppliers in Surrey but also follow a few tips to ensure your safety.

concrete safety tips

Few Tips To Ensure Your Safety When Working With Concrete In Surrey

·   Keep Your Skin Protected

Concrete burns are one of the most common threats people in the construction industry have to face. The caustic and abrasive texture of concrete can lead to severe irritation and burn your skin. The danger of concrete burns is more if you are using fresh concrete. It is mandatory for construction workers to always keep their skin covered. Long sleeve shirts, protective eyewear, gloves and long pants are vital components of their uniform. Wash off your skin immediately if they come in contact with fresh concrete.

·   Use Safe Tools

The tools used by construction workers when working with concrete can also pose safety hazards. This is why they should know how to handle them safely, operate properly and store them appropriately. They should wear hard hats and use the latest tools using proper grips and techniques. The construction workers should also communicate with the machine operators regarding the clearance and movement of the machinery.

·   Stay Aware Of Silica

If you are willing to stay away from construction hazards, be aware of silica. Ensuring silica safety is a must when using concrete. Construction workers should avoid getting exposed to crystalline silica as it is considered to be a carcinogen. Crystalline silica can lead to severe lung diseases like lung cancer. OSHA has made medical surveillance of workers mandatory to ensure that they are not being exposed to more than 50 micrograms of silica dust per cubic meter of air.

·   Look Before You Step

New concrete can also lead to tripping hazards in a wide variety of ways. Misplaced tools, rebar and uneven ground can make construction workers trip and fall, thus injuring themselves. All walking paths should be clear. Workers should watch their steps while walking. The easiest way to keep their feet protected is by wearing rubber boots which helps in creating more traction.

·   Lift Safely

Workers have to often lift and move heavy objects on construction sites. They should move objects using safe lifting techniques. If they feel that some object is too heavy, they should be ready to work in teams and pairs. Workers should determine the right amount of fresh concrete to be loaded in the shovel so that they can lift it with confidence. Lifting injuries generally happen when they twist their back accidentally while lifting heavy objects.

Time to follow the tips stated above and ensuring your safety when working with concrete will become easier.

Hire The Best Concrete Suppliers In Croydon For High-Quality Concrete Work

The focus of every construction worker is always on providing the highest standard of concrete work. If you also want your construction project to be both beautiful and durable, the first thing you need to do is to choose a renowned concrete supplier. They should have years of experience in providing high-quality concrete in Croydon. Since their focus is always on maintaining their reputation, you can stay assured that they will provide quality concrete. Just discuss your concrete needs with them, and they will suggest the best concrete variety which will help construction workers deliver great work.

concrete company Croydon

4 Factors Concrete Suppliers Consider Before Starting Concrete Work

·   Condition Of The Soil

The longevity of a specific structure is mainly dependent on the condition of the ground which it has been constructed. It is advisable to avoid land comprising of clay and fine particles if you don’t want the structure to become vulnerable to cracking. This is because it takes a long time for water to drain in the soil, which increases the water table. If you have to build the structure in such ground, make sure there are at least 2 inches of gravel or engineered soil placed below the concrete slabs.

· Dowel Pins

Dowel rods and dowel pins are generally used in civil constructions and provide a mechanical connection between two slabs without restricting its horizontal movement. Ask the contractors to use them at places where the concrete meets the foundation of your home. This prevents the concrete slab from settling in the foundation which would have otherwise drained water towards your home, flooding the crawl spaces and basements. The rebar mats help in resisting bending forces.

·   Thickness

The thickness of the concrete structure is a vital thing to consider, so stay away from contractors who are too greedy or lazy to pour concrete of sufficient depth. Not only will it harm the durability of the concrete structure, but cracks will develop all over it, and finally it will fail. If you are not sure about the proper thickness, talk with your concrete suppliers in Croydon. Generally, the poured concrete should be around 4 inches thick if you are doing some residential flatwork. You will get good concrete work if its thickness is checked before the slab is poured.

·   Control Joints

The primary task of concrete joints is to create weak points on the surface of the concrete slabs so that cracking occurs inside the joint and not on the surface. This is why they are known by the term control joints and are placed inside the concrete slab. The maximum distance between two joints should be 12 feet in each direction. Just check whether the contractors are cutting the joints to the proper depth.

Since you are now aware of the factors which impact the quality of concrete work, it’s time you start with your construction project.