Для приготовления бетонной смеси берут 1 часть цемента 4 части песка: Attention Required! | Cloudflare

» Правильное соотношение цемента, песка, щебня и воды для приготовления бетона

Бетон нашел применение в различных сферах строительства. Его основными составляющими являются: песок, вода, цемент и гравий. Для получения качественной смеси они должны использоваться в определенном соотношении. Серьезное отклонение от нормы приведет к образованию раствора низкого качества, который нельзя использовать для возведения фундамента или других элементов строений.

Соотношение компонентов в цементно-песчаном растворе

Для приготовления бетонной смеси нельзя использовать только цемент и воду. Бетон, полученный на их основе, не обладает хорошими показателями прочности и морозостойкости. Здание, возведенное с использованием «низкокачественной» смеси, даст усадку.

Песок — важная составляющая бетона. Необходимо, чтобы он был чистым. Допускается наличие мелкого гравия, глины и других примесей, но не более 5% от его массы.

Материал с мелким зерном не подходит для приготовления бетона. Допустимо использование песка с размерами частиц 2-3 мм.

Сколько песка присутствует в бетоне различных марок?

От количества песка в смеси зависит марка материала.

• М50 — при использовании цемента М200 соотношение песка и цемента равно 1:3, при М400 — 1:4;
• М100 — при использовании материала М200 соотношение 1:2, при М400 — 1:3;
• М75 ― при использовании материала М200 соотношение 1:1,25, при М400 — 1:1,35.

В растворы, в которых отсутствует щебень, потребуется дополнительное введение песка. Так, при изготовлении бетона М10 с использованием материала М200 соотношение составит 1:6, в марке бетона М25 — 1:4.

В некоторых случаях соотношение компонентов в растворе бетона может быть увеличено или уменьшено. Чтобы повысить прочность необходимо увеличить количество цемента в его составе. Если повысить количество цемента М300 на 10%, то получится раствор, который по своим характеристикам аналогичен смеси с использованием цемента М400.

При использовании слишком мелкого песка рекомендуется снизить его количество на 10%, в противном случае прочность материала на изгиб и сжатие будет низкой.

Песок и щебень смешивается постепенно с добавлением небольшого количества воды. Бетонную смесь рекомендуется готовить небольшими порциями, чтобы она не успевала «схватиться».

Пропорции песка, цемента и щебня

Использование щебня позволяет снизить себестоимость бетона и повысить его прочность. Чтобы готовый раствор обеспечивал высокое сцепление, необходимо использовать заполнитель с небольшими фракциями и рифленой поверхностью.

Стандартное соотношение цемента, песка и щебня составляет 1:3:2. Это означает, что щебня должно быть меньше, чем песка, но больше чем главного компонента — цемента.

Воды в растворе не должно быть много, иначе она негативно скажется на прочности материала. В идеале ее количество должно составлять до 25% от общей массы. Для приготовления качественной смеси используют только чистую воду без примесей, лучше фильтрованную.

Если в качестве материалов используется мокрый песок и щебень, то количество воды можно уменьшить, при применении сухих компонентов — увеличить.

Соотношение цемента и ПГС (ОПГС)

ПГС — это песчано-гравийная смесь, состоящая из 2-х компонентов. Именно место добычи песка и гравия (морское или речное дно) оказывает влияние на качество смеси. Гравий не должен содержать глину, снижающую эксплуатационные характеристики бетона. Размер камушков для ПГС должен составлять от 1 до 8 см.

ПГС используется для возведения фундаментов и дорожных покрытий. Основное отличие ПГС от ОПГС — искусственное увеличение количества гравия в обогащенной смеси. Так, его количество в ПГС составляет до 25%, в ОПГС — 25-28%.

Для получения качественной бетонной смеси необходимо соблюдать пропорцию цемента, воды и ПГС в ней. Для изготовления качественного бетона потребуется 1 часть основного материала, 4 части ПГС и 0,5 частей воды. В качестве части учитывается вес компонентов, а не объем. Добавлять в этот раствор песок не нужно, так как он уже присутствует в ПГС.

Указанное выше соотношение не является стандартом. В каждом случае необходимо отталкиваться от назначения бетонной смеси, качества щебня и песка, а также применения пластификаторов и других материалов.

Что нужно брать за основу — объем или вес?

За основу измерения берется масса одной единицы цемента. Остальные компоненты берутся также по весу. Количество воды определяется частью от веса. Например: для производства смеси берется 12 кг основного материала и 6 кг воды, то водоцементное соотношение вычисляется так: 6/12 = 0,5 литров воды.

Массовая доля песка и цемента в бетонной смеси зависит от следующих факторов: марки цемента, количества воды и фракций сыпучих компонентов. При возведении ответственных сооружений используется бетон марки М400 и выше. Для его получения необходимы цемент, песок и щебень в соотношении 1:1,2:2,7, при условии, что будет использоваться цемент 400.

90000 Concrete: The Basic Mix 90001 Concrete: The Basic Mix 90002 A general teacher’s guide for concrete preparation 90003 90004 The physical properties of density and strength of concrete are determined, in part, by the proportions of the three key ingredients, water, cement, and aggregate. You have your choice of proportioning ingredients by volume or by weight. Proportioning by volume is less accurate, however due to the time constraints of a class time period this may be the preferred method.90005 90004 A basic mixture of mortar can be made using the volume proportions of 1 water: 2 cement: 3 sand. Most of the student activities can be conducted using this basic mixture. Another «old rule of thumb» for mixing concrete is 1 cement: 2 sand: 3 gravel by volume. Mix the dry ingredients and slowly add water until the concrete is workable. This mixture may need to be modified depending on the aggregate used to provide a concrete of the right workability. The mix should not be too stiff or too sloppy.It is difficult to form good test specimens if it is too stiff. If it is too sloppy, water may separate (bleed) from the mixture. 90005 90004 Remember that 90009 water is the key ingredient. 90010 Too much water results in weak concrete. Too little water results in a concrete that is unworkable. 90005 90004 90013 Suggestions: 90014 90015 90005 90017 90018 If predetermined quantities are used, the method used to make concrete is to dry blend solids and then slowly add water (with admixtures, if used).90019 90018 It is usual to dissolve admixtures in the mix water before adding it to the concrete. Superplasticizer is an exception. 90019 90018 Forms can be made from many materials. Cylindrical forms can be plastic or paper tubes, pipe insulation, cups, etc. The concrete needs to be easily removed from the forms. Pipe insulation from a hardware store was used for lab trials. This foam-like material was easy to work with and is reusable with the addition of tape. The bottom of the forms can be taped, corked, set on glass plates, etc.Small plastic weighing trays or Dairy Queen banana split dishes can be used as forms for boats or canoes. 90019 90018 If compression tests are done, it may be of interest to spread universal indicator over the broken face and note any color changes from inside to outside. You may see a yellowish surface due to carbonation from CO 90025 2 90026 in the atmosphere. The inside may be blue due to calcium hydroxide. 90019 90018 To answer the proverbial question, «Is this right?» a slump test may be performed.A slump test involves filling an inverted, bottomless cone with the concrete mixture. A Styrofoam or paper cup with the bottom removed makes a good bottomless cone. Make sure to pack the concrete several times while filling the cone. Carefully remove the cone by lifting it straight upward. Place the cone beside the pile of concrete. The pile should be about 1/2 to 3/4 the height of the cone for a concrete mixture with good workability. (SEE DIAGRAM) 90015 90019 90018 To strengthen samples and to promote hydration, soak concrete in water (after it is set).90019 90018 Wet sand may carry considerable water, so the amount of mix water should be reduced to compensate. 90019 90018 Air bubbles in the molds will become weak points during strength tests. They can be eliminated by: 90015 90037 90018 i. packing the concrete. 90019 90018 ii. Tapping the sides of the mold while filling the mold. 90019 90018 iii. «Rodding» the concrete inside the mold with a thin spatula. 90019 90044 90019 90018 Special chemicals called «water reducing agents» are used to improve workability at low water to cement ratios and thus produce higher strengths.Most ready-mix companies use these chemicals, which are known commercially as superplasticizers. They will probably be willing to give you some at no charge. 90019 90018 You can buy a bag of cement from your local hardware store. A bag contains 94 lb. (40kg) of cement. Once the bag has been opened, place it inside a garbage bag (or two) that is well sealed from air. This will keep the cement fresh during the semester. An open bag will pick up moisture and the resulting concrete may be weaker.Once cement develops lumps, it must be discarded. The ready mix company in your area may give you cement free of charge in a plastic pail. 90019 90050 90002 Video Clip 90003 90053 Next Topic: Experiment 1 90015 Concrete Table of Contents 90015 MAST Home Page 90056 .90000 Setting Posts without Mixing | QUIKRETE: Cement and Concrete Products 90001 90002 90003 Project Instructions 90004 90005 90006 When working with cement-based products, always wear eye protection and waterproof gloves. 90007 90008 90005 90010 Step 1 90011 90002 Dig post hole so diameter of the hole is 3 times the width of the post (i.e., the hole for a 4 «wood post should be about 12 inches wide).The depth of the hole should be 1 / 3-1 / 2 the post height above ground (i.e., a 6-foot tall fence would require a hole depth of at least 2 feet). 90008 90005 90010 Step 2 90011 90002 Add about 6 inches of QUIKRETE All-Purpose Gravel into the bottom of the hole. Then compact and level the gravel using a post or 2×4. 90008 90005 90010 Step 3 90011 90002 Set the post into the hole and attach 2×4 braces to adjacent sides of the post.90008 90005 90010 Step 4 90011 90002 Use a level to position the post perfectly vertical. 90008 90005 90010 Step 5 90011 90002 Fill the hole with Fast-Setting Concrete up to 3 to 4 inches below ground level. 90008 90005 90010 Step 6 90011 90002 Pour about a gallon of water per 50 lb bag into the hole and allow the water to saturate the concrete mix.90008 90005 NOTE: mix will set hard in 20 to 40 minutes 90008 90005 90010 Step 7 90011 90002 Wait about 4 hours to begin constructing your fence or applying heavy weight to your post. 90008 90002 90003 Shopping List 90004 90005 90006 90010 (Optional) 90011 90007 90008 90055 90056 QUIKRETE Building form 90057 90056 Shovel 90057 90056 Plastic mixing tub 90057 90062 .90000 The Ultimate Guide to Mortar Mix Ratios [Updated 2019] 90001 90002 This page is part of our blog and is all about mortar mixes for home improvement and construction projects. 90003 90002 Whether you’re laying bricks, pointing, renewing chimney flaunching, laying screed or rendering, we have the best mix ratios for you. 90003 90002 Tradespeople and builders often use different terms to describe cement, concrete and mortar, so here’s a quick guide designed to avoid confusion: 90003 90002 90009 Cement 90010 is a greyish coloured powder that is mixed with sand and / or other aggregates to create concrete or mortar.90003 90002 90009 Mortar 90010 is a mixture of fine sand particles, cement, water and sometimes lime. It’s typically used for brick laying and pointing. It is usually laid in thin layers as thicker layers may crack during the drying process. 90003 90002 90009 Concrete 90010 is a mixture of aggregates such as crushed rock, gravel and sand that is mixed with cement and water. Concrete is usually laid in thick layers, the larger particles prevent cracking during the drying process. 90003 90002 90009 Soft sand 90010 is also known as building sand and contains fine grains of sand and is used for bricklaying, pointing and where thin layers of mortar are required.90003 90002 90009 Sharp sand 90010 is more coarse than building / soft sand and is perfect for mixing with other sands to prevent cracking during the drying process. It’s often used in situations where a slightly thicker layer of mortar is required — chimney flaunching, bedding roof tiles and many garden projects will require sharp sand. 90003 90002 90009 Plasterers sand 90010 is not as coarse as sharp sand but not as fine as soft sand. It’s washed to remove salts and clay residue that could cause efflorescence (salting).90003 90002 90009 Lime 90010 can be used as an alternative to cement in some mixes or used in conjunction with it. Lime allows materials such as bricks to breathe, it’s commonly used on older period buildings with soft, permeable bricks that would likely crack if cement was used. 90003 90002 90009 Plasticiser 90010 is a liquid that is added to the mix to make the material easier to work with and it also slows down the curing process slightly. It makes a typical mortar mix sticky and easier to point over.90003 90002 90009 Waterproofer 90010 is different to plasticiser. Does what it says on the tin and is often used when rendering. 90003 90002 90009 Frost proofers, accelerators and colour additives 90010 can be included in the mix as required. 90003 90048 Related Products Hand-Selected by Us 90049 90002 We think you might like these products: 90003 90052 Wolfcraft Mixer Paddle 90053 90002 90055 90003 90002 Make cement and plaster mixing easy with this heavy-duty mixer paddle. Suitable for most electric drills.90058 Check Price Here 90003 90052 60 Litre H / Duty Mixing Tub 90053 90002 90063 90003 90002 Perfect for mixing small amounts of cement or plaster in confined spaces, less mess and easy storage. 90058 Check Price Here 90003 90052 70 Litre Electric Mixer 90053 90002 90071 90003 90002 With an impressive 70 litre capacity, this electric mixer will save you time on any job, large or small. 90058 Check Price Here 90003 90052 60 Litre H / Duty Mixing Tub 90053 90002 90079 90003 90002 Perfect for DIYers and those on a limited budget is this 5-piece trowel set by Draper Redline.90058 Check Price Here 90003 90052 What Happens if You Make the Mortar Too Weak? 90053 90002 Not only will the mortar fail to bind sufficiently, it may also crumble after a short amount of time or wash away after minimal weathering. 90003 90002 The photo below shows a ridge tile that was bedded onto a very weak and totally unsuitable mortar mix. 90003 90002 The tile was not secured in place and the «mortar» could be crushed into small particles by simply squeezing it in my hand: 90003 90002 90093 90003 90052 What Happens if the Mix is ​​Too Strong? 90053 90002 Too strong a mix, i.e made with too much cement and your mortar may dry too quickly, shrink and crack. 90003 90002 Cracking can be avoided by reducing the amount of cement in the mixture and ensuring the mortar is wet enough. 90003 90002 The photo below shows cracked mortar — typical issues that can occur if the mix is ​​too strong: 90003 90002 90104 90003 90052 Best Mortar Mixes 90053 90002 Below you’ll find our guide to mortar mixes: 90003 90110 Bricklaying 90111 90002 The best mix will depend on the type of brick and the location of the wall.For most domestic builds such as house building, use one of these mixes: 90003 90002 4 parts soft sand with 1 part cement, add water and plasticiser. 90003 90002 For soft older bricks already bedded onto a lime based mortar; a lime and sand mix should be used, the ratio will depend on the type of lime and how much water content it has. This page has more detailed information about lime / sand ratios. 90003 90002 For retaining walls or anywhere likely to be in regular contact with water, 3 parts soft sand and one part cement, 1 part lime is optional depending on the type of brick / block.90003 90002 For Airtec blocks above DPC, 6 parts soft sand, 1 part cement and 1 part plasticiser or 5 parts soft sand and 1 part cement. 90003 90002 For blocks below DPC, 4.5 parts soft sand, 1 part cement and 1 part lime or 4 parts soft sand and 1 part cement 90003 90002 This page contains a price guide for wall repointing. 90003 90110 Chimneys 90111 90002 For chimney repointing to a modern home, the best mix will depend on how exposed the chimney is and it’s location. For chimneys in wind swept rainy parts of the country use a mix of 3 parts soft sand and 1 part cement.For softer or more permeable bricks, 4 parts sand, half part cement and 1 part lime can be used. Plasticiser is optional. 90003 90002 Chimney flaunching will receive a lot of rainfall so the mix should be strong, this prevents it washing out. Because flaunching is laid several inches thick, add sharp sand to the mix to avoid cracking during the drying process. 2 or 3 parts soft sand 1 part sharp sand, 1 cement and half-part lime is optional. 90003 90002 or 90003 90002 1 part soft sand, 2 parts sharp sand, 1 cement, half part lime is optional.90003 90002 For older period homes, a lime-based should be used instead of cement. 90003 90002 Chimney maintenance costs are published on this page. 90003 90110 Paving Mortar Mix 90111 90002 For bedding under the slabs use 5 parts sharp sand, 1 part soft sand and 1 cement. 90003 90002 For pointing use 4 parts soft sand and 1 part cement. For high traffic areas, a stronger mix of 3 parts soft sand and 1 part cement can be used. 90003 90002 This page contains a price guide for a new patio. 90003 90110 Render Mortar Mix (Modern Buildings) 90111 90002 The first coat of render should ideally be slightly stronger than the second coat.While some tradespeople make the two mixes the same strength, the second coat should never be stronger than the first coat. 90003 90002 A pure soft sand mix should not be used when rendering. It’s preferable to use either sharp sand, plasterers sand or a mixture of two. Soft sand can be added to the mix but we feel it should not comprise more than 25% of the entire mix. 90003 90002 The first coat of render can be 2 parts plasterers sand and 2 parts sharp sand, 1 part cement and half part lime. Waterproofer can be applied to the first coat if the property is modern.90003 90002 The second coat must be slightly weaker than the first, so 3 parts plasterers sand, 2 parts sharp sand, 1 part cement and half lime. Plasticiser can be used in the second coat. 90003 90002 For locations in the east and south of the country or any sheltered location that experiences less windswept rain, a slightly weaker mix can be used. For the first coat 4 parts sharp / plasterers and for the second coat 5 parts sharp / plasterers. 90003 90002 This page contains a guide to rendering prices in the UK.90003 90052 Render (Period buildings) 90053 90002 Modern buildings are constructed with thermal efficiency in mind and sealants, waterproofing materials and cement based products can be used. 90003 90002 Period properties are designed to breathe. Floors and walls are often constructed with lime, a material that lets the moisture in the building escape. Covering breathable materials with non-breathable cement, gypsum plaster or waterproofing sealers can lead to significant damp problems. 90003 90002 For period properties we suggest seeking the advice of a specialist who understands how older buildings are designed to breathe.90003 90110 Floor Screed Mix 90111 90002 For modern homes: 4 parts sharp sand and 1 part cement. Although anything from 3-5 parts sharp sand to 1 part sand would be acceptable for most situations. 90003 90002 For period buildings: Lay a lime-based screed as the floor needs to breathe. If you do not, the cement in the screed will push moisture towards the walls where the soft bricks and plaster will absorb the water. 90003 90110 Best Mortar Mix For Roof Tiles 90111 90002 Because roof tiles are located in an exposed location that’s likely to experience rainfall, a strong mix should be used.Unfortunately, some profiled roof tiles require a very thick bedding of mortar, so to reduce the risk of cracking, sharp sand should be introduced to the mix for most tiles. 90003 90002 All tiles except Plain tiles — 2 parts soft sand, 1 part sharp sand and 1 part cement. 90003 90002 For tiles where only a thin bedding of mortar is required (i.e. Plain tiles) 3 parts soft sand *, 1 part cement and plasticiser. 90003 90002 * we recommend choosing a soft sand that is fairly coarse, avoid soft sands that are at the «silty» end of the spectrum.90003 90002 90009 Do not forget; 90010 to meet new British Standards requirements for roof fixings, you can not rely on mortar to secure the tiles in place. Ridges, valley tiles and verges should be secured with a nail or clip, either in addition to the mortar in replacement of it, this is called a dry fix method. This page contains information about the differences between a dry and wet fixing method. 90003 90002 Roof repair prices can be located on our main price list here. 90003 90052 How Much Water is Too Much? 90053 90002 The firmness of the wet mortar can be altered by changing the type of sand, the sand / cement ratio and the amount of water added to the mix.90003 90002 Most bricks and blocks are quite porous and as only a thin layer of mortar is required, a wet or «sloppy» mix is ​​often preferable. 90003 90002 Some roof tiles require a bedding layer of mortar that’s several inches thick and a wet / sloppy mix would not be suitable, it would slump off the tile. For roofing projects, a firmer mixture is generally required. 90003 90002 Needless to say that mortar should never be so firm that it does not have enough water content to create a chemical reaction.Neither should it be so sloppy that it’s impossible to work with. 90003 90052 What’s the Lowest Temperature I Can Use Mortar? 90053 90002 5 degrees is the lowest temperature that mortar can be laid. Any colder and there is a risk of frost which will weaken the finished mortar. Frost proofers can be added to the mortar but should not be relied upon. 90003 90052 Additives 90053 90002 90009 Frost proofer 90010 should not be relied upon to protect mortar from freezing conditions. It can be used but its reliability is debatable.90003 90002 90009 Colourants 90010 can be used but only use as much as you need and avoid excessive amounts. 90003 90002 90009 Accelerators 90010 speed up the drying time but often leave you with little time to work with the mortar before it starts to set. If you continue to work with a mortar that has set, you’ll reduce the strength of the finished mortar. Therefore, you should only use them when absolutely necessary and not as a matter of course. 90003 90052 Concrete and Ready Mix Prices 90053 90002 If you do not want to mix the materials yourself, you can get it delivered by a ready mix supplier.90003 90002 This is the perfect option for large projects. 90003 90002 See ready mix concrete prices here. 90003 90048 Related Hand Selected by Us 90049 90002 We think you might like these products: 90003 90052 Wolfcraft Mixer Paddle 90053 90002 90055 90003 90002 Make cement and plaster mixing easy with this heavy-duty mixer paddle. Suitable for most electric drills. 90058 Check Price Here 90003 90052 60 Litre H / Duty Mixing Tub 90053 90002 90063 90003 90002 Perfect for mixing small amounts of cement or plaster in confined spaces, less mess and easy storage.90058 Check Price Here 90003 90052 70 Litre Electric Mixer 90053 90002 90071 90003 90002 With an impressive 70 litre capacity, this electric mixer will save you time on any job, large or small. 90058 Check Price Here 90003 90052 60 Litre H / Duty Mixing Tub 90053 90002 90079 90003 90002 Perfect for DIYers and those on a limited budget is this 5-piece trowel set by Draper Redline. 90058 Check Price Here 90003 90264.