水泥穩(wěn)定碎石是目前路面工程中使用最多的基層材料之一了。雖然具有諸如干縮和溫縮特性，反射裂縫等問題，但并不影響它的廣泛應用。設計中也經常看到諸如“5%水泥穩(wěn)定碎石”等表述，很多時候也只是看著大多數人在用而并不知道為什么是5%或其他比例，也不知道其他比例可不可以。

　　Cement stabilized crushed stone is currently one of the most commonly used base materials in pavement engineering. Although it has issues such as dry shrinkage and thermal shrinkage, reflection cracks, etc., it does not affect its wide application. In design, expressions such as "5% cement stabilized crushed stone" are often seen, and many times it is only observed that most people are using it without knowing why it is 5% or other proportions, and whether other proportions are acceptable.

　　水泥穩(wěn)定碎石基層施工

　　Construction of cement stabilized crushed stone base

　　這其實涉及到的是水穩(wěn)碎石基層中的水泥摻量問題，作如下總結。

　　This actually involves the issue of cement dosage in the water stable crushed stone base, which can be summarized as follows.

　　2質量比還是體積比首先，5%水泥穩(wěn)定碎石中的5%是質量比，而非體積比或其他什么比例。即水泥的質量與集料（碎石、石屑等）質量之比為5:100，水泥占集料質量的5%。例如，若集料質量為1000千克，那么水泥質量就是1000×5%=50千克。其實工程中的很多百分比都是質量比，比如摻灰改良等等。這其實很好理解。首先，材料質量更容易準確測量，尤其是在大規(guī)模工程中。體積可能會因為材料的松散程度或顆粒大小而變化，比如沙子如果潮濕或者壓緊，同樣的體積實際質量會不同，這樣體積比可能不準確。而質量是固定的，不會受這些因素影響，所以更可靠。另外，化學反應通常基于質量，比如水泥的水化反應，需要精確的質量比例來保證反應完全，否則可能影響強度。體積的話，不同材料的密度不同，同樣體積可能質量差異大，導致化學反應比例失調。還有工程設計的標準更傾向于質量比，因為計算起來更方便。比如配合比設計時，質量可以直接加減乘除，而體積需要考慮各材料的密度換算，步驟更多，容易出錯。

　　Is it a mass ratio or a volume ratio? Firstly, 5% of cement stabilized crushed stone is a mass ratio, not a volume ratio or any other ratio. The ratio of the quality of cement to the quality of aggregate (crushed stone, stone chips, etc.) is 5:100, and cement accounts for 5% of the mass of aggregate. For example, if the aggregate mass is 1000 kilograms, then the cement mass is 1000 × 5%=50 kilograms. In fact, many percentages in engineering are quality ratios, such as fly ash improvement and so on. This is actually easy to understand. Firstly, material quality is easier to accurately measure, especially in large-scale engineering projects. The volume may vary due to the looseness or particle size of the material, for example, if sand is wet or compacted, the actual mass of the same volume may be different, which may result in inaccurate volume ratios. And the quality is fixed and not affected by these factors, so it is more reliable. In addition, chemical reactions are usually based on quality, such as the hydration reaction of cement, which requires precise mass ratios to ensure complete reaction, otherwise it may affect strength. In terms of volume, different materials have different densities, and the same volume may have significant differences in mass, leading to an imbalance in chemical reaction proportions. The standards for engineering design are more inclined towards quality ratio because they are more convenient to calculate. For example, in mix design, mass can be directly added, subtracted, multiplied, and divided, while volume needs to consider the density conversion of each material, which involves more steps and is prone to errors.

　　3水泥摻量代表什么水泥作為膠粘材料，其摻量最直接反映的就是基層的強度。《公路路面基層施工技術細則》（JTGF20-2015）中，對水泥穩(wěn)定碎石中的水泥劑量并沒有強制性的要求，只有指導性的意見，配合比試驗時的推薦摻量如下：水泥穩(wěn)定碎石的水泥摻量其實是強度導向，即強度滿足要求就行了，包括設計中的5%也只是設計配合比。

　　What does the cement content represent? As a bonding material, the cement content most directly reflects the strength of the base layer. In the "Technical Guidelines for Construction of Highway Pavement Base" (JTGF20-2015), there is no mandatory requirement for the cement dosage in cement stabilized crushed stone, only guiding opinions. The recommended dosage for mix proportion testing is as follows: the cement dosage of cement stabilized crushed stone is actually strength oriented, that is, as long as the strength meets the requirements, including the 5% in the design, which is only the design mix proportion.

　　水泥摻量只是影響強度的其中一個參數，不同的集料下，設計5%，可能實際摻3%就達到設計強度了，也有可能要摻更多的水泥才能達到設計強度。規(guī)范也規(guī)定了不能隨便無限調整，有一個最小的要求，如下表。并不提倡通過無限提高水泥摻量來提高基層強度，而是通過優(yōu)化級配和原材料質量等方式。

　　The cement content is only one parameter that affects the strength. For different aggregates, a design of 5% may achieve the design strength with an actual content of 3%, or more cement may need to be added to achieve the design strength. The regulations also stipulate that adjustments cannot be made arbitrarily and infinitely, with a minimum requirement as shown in the table below. We do not advocate increasing the cement content infinitely to improve the strength of the base layer, but rather optimizing the grading and raw material quality.

　　摻量的影響水泥劑量的多少與水泥穩(wěn)定材料的強度、彈性模量、溫縮系數和干縮系數大小有直接關系。隨著水泥用量增加，其強度和彈性模量增加，但是收縮系數也隨之增加。為減少半剛性基層的開裂，應盡量提高基層材料的抗拉強度，降低材料的彈性模量、溫縮系數和干縮系數，減小基層內部的最大收縮應力。

　　The influence of dosage on cement dosage is directly related to the strength, elastic modulus, thermal shrinkage coefficient, and drying shrinkage coefficient of cement stabilized materials. As the amount of cement increases, its strength and elastic modulus increase, but the shrinkage coefficient also increases. To reduce cracking in semi-rigid base layers, the tensile strength of the base material should be increased as much as possible, the elastic modulus, thermal shrinkage coefficient, and dry shrinkage coefficient of the material should be reduced, and the maximum shrinkage stress inside the base layer should be minimized.

　　因此，在滿足要求的情況下，宜采用最小的水泥用量以降低彈性模量和收縮系數。

　　Therefore, it is advisable to use the minimum amount of cement to reduce the elastic modulus and shrinkage coefficient while meeting the requirements.

　　價格的差異不同摻量的水泥穩(wěn)定碎石，價格差異多少？下面簡單測算一下。以最常用的20cm水泥穩(wěn)定碎石基層為例，水穩(wěn)碎石的干密度按2.3噸/立方米，那么，每平米水穩(wěn)碎石基層質量0.2*2.3=0.46噸。水泥價格按500元每噸，可算出水泥摻量相差0.5%時，水泥穩(wěn)定碎石價格相差約2元/噸，也就是0.46*2=0.92元/平米。所以，對于20厘米厚的水穩(wěn)碎石基層，水泥摻量相差0.5%，價格差約為0.92元每平米，不到1塊錢。當然，實際價格差會因材料價格、水穩(wěn)碎石干密度等因素的不同而有所變化。

　　What is the price difference for cement stabilized crushed stone with different dosages? Below is a brief calculation. Taking the most commonly used 20cm cement stabilized crushed stone base as an example, if the dry density of water stabilized crushed stone is 2.3 tons/cubic meter, then the mass of water stabilized crushed stone base per square meter is 0.2 * 2.3=0.46 tons. If the cement price is 500 yuan per ton, it can be calculated that when the cement content differs by 0.5%, the price difference of cement stabilized crushed stone is about 2 yuan/ton, which is 0.46 * 2=0.92 yuan/square meter. So, for a 20cm thick water stable crushed stone base, the difference in cement content is 0.5%, and the price difference is about 0.92 yuan per square meter, less than 1 yuan. Of course, the actual price difference may vary due to factors such as material prices and the dry density of water stable crushed stone.

　　本文由  濟南水穩(wěn)碎石 友情奉獻.更多有關的知識請點擊  http://www.81tyre.com/   真誠的態(tài)度.為您提供為全面的服務.更多有關的知識我們將會陸續(xù)向大家奉獻.敬請期待.

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