厂拌冷再生三大“门派”

　　Three major "schools" of factory mixed cold recycling

　　随着我国早期建成的公路陆续进入大中修期，路面维修养护产生的废旧沥青混合料处理成为一项严峻的环境与资源课题。厂拌冷再生技术作为一种常温拌和的绿色路面修筑技术，能够将废旧沥青路面铣刨料再生利用，兼具显著的效益和经济效益，被交通运输部列为推广的低碳新技术一、什么是厂拌冷再生技术？厂拌冷再生就是将旧沥青路面材料运到拌和厂，经过破碎、筛分后，按照一定比例添加新集料、活性填料、再生结合料和水等材料，在常温下充分拌和，形成新的再生混合料，再运到施工现场进行摊铺、碾压，终形成路面结构层的一种沥青路面再生技术。简单来说，就是让“废料”变“原料”，实现沥青路面的循环再利用。

　　With the early construction of highways in China entering the period of major and medium repairs, the disposal of waste asphalt mixture generated from road maintenance and upkeep has become a serious environmental and resource issue. Factory mixed cold recycling technology, as a green pavement construction technology that mixes at room temperature, can efficiently recycle and reuse waste asphalt pavement milling materials, with significant environmental and economic benefits. It has been listed as a key low-carbon, environmentally friendly and energy-saving new technology promoted by the Ministry of Transport. What is factory mixed cold recycling technology? Factory mixed cold recycling is a technology for asphalt pavement recycling that involves transporting old asphalt pavement materials to a mixing plant, crushing and screening them, adding new aggregates, active fillers, recycled binders, and water in a certain proportion, fully mixing them at room temperature to form a new recycled mixture, and then transporting them to the construction site for paving and rolling, ultimately forming a pavement structure layer. Simply put, it means turning "waste" into "raw materials" to achieve the recycling and reuse of asphalt pavement.

　　二、厂拌冷再生的分类

　　2、 Classification of factory mixed cold recycling

　　按照所用结合料的不同，厂拌冷再生又可以分为泡沫沥青冷再生、乳化沥青冷再生和水泥冷再生三种方式。泡沫沥青冷再生：利用高温沥青与少量水产生剧烈膨胀，形成大量泡沫状沥青，在常温下裹覆旧料和集料。乳化沥青冷再生：将沥青加热后通过机械剪切分散到含有乳化剂的水中，形成常温可流动的乳白色液体，与旧料拌和。水泥稳定冷再生：直接添加水泥和水，依靠水泥水化产生强度，本质上是一种半刚性基层材料。三者虽然都是“冷拌冷铺”，但成型的原理、材料性质、路用性能天差地别。

　　According to the different binders used, plant mix cold recycling can be divided into three modes: foam asphalt cold recycling, emulsified asphalt cold recycling and cement cold recycling. Cold recycling of foam asphalt: use high temperature asphalt and a small amount of water to produce violent expansion, form a large amount of foam asphalt, and wrap old materials and aggregates at room temperature. Emulsified asphalt cold regeneration: After heating, the asphalt is mechanically sheared and dispersed into water containing emulsifiers to form a room temperature flowable milky white liquid, which is mixed with the old material. Cement stabilized cold regeneration: Directly adding cement and water, relying on cement hydration to generate strength, essentially a semi-rigid base material. Although all three are "cold mix and cold lay", their forming principles, material properties, and road performance are vastly different.

　　三、泡沫沥青冷再生——低调的实力派

　　3、 Cold recycling of foam asphalt -- low-key strength school

　　（1）原理：瞬间“爆炸”的泡沫泡沫沥青可不是加了发泡剂的洗面奶。它的制备很硬核：将160℃以上的热沥青与少量常温水（约沥青质量的1%~3%）注入发泡腔，水遇高温瞬间汽化，沥青体积急剧膨胀10~20倍，形成无数细小的沥青泡沫。这些泡沫状沥青在破裂瞬间，会像“胶水”一样选择性裹附在细集料（主要是0.075mm~2.36mm颗粒）表面，形成“点焊”结构。粗集料则被水泥或矿粉填充，终形成以沥青粘结为主、水泥水化为辅的复合强度。

　　(1) Principle: instant "explosion" of foam foam asphalt is not facial cleanser with foaming agent. Its preparation is very hard core: hot asphalt above 160 ℃ and a small amount of normal temperature water (about 1%~3% of the asphalt mass) are injected into the foaming chamber. When the water meets the high temperature, it vaporizes instantly, and the asphalt volume expands 10~20 times rapidly, forming numerous small asphalt foam. At the moment of cracking, these foam asphalt will selectively bind to the surface of fine aggregate (mainly 0.075mm~2.36mm particles) like "glue", forming a "spot welding" structure. Coarse aggregate is filled with cement or mineral powder, ultimately forming a composite strength mainly composed of asphalt bonding and supplemented by cement hydration.

　　（2）关键特点对旧料要求：对旧料中细颗粒含量（≤0.075mm）有一定要求，通常建议通过率3%~8%以上。强度形成：初期依靠压实和水泥水化获得早期强度，后期依靠沥青泡沫破裂后残留的沥青粘结力持续增长。养生时间：常温下一般养生2~7天即可铺筑面层。路用性能：抗疲劳性能和抗反射裂缝能力优异，且不怕水（水稳定性好于乳化沥青）。

　　(2) Key characteristics for old materials: There are certain requirements for the content of fine particles (≤ 0.075mm) in the old materials, and it is usually recommended to have a pass rate of 3% to 8% or more. Strength formation: early strength is obtained by compaction and cement hydration at the initial stage, and the residual asphalt cohesive force after the asphalt foam bursts at the later stage continues to grow. Health preservation time: Generally, the surface layer can be laid after 2-7 days of health preservation at room temperature. Road performance: Excellent fatigue resistance and anti reflection cracking ability, and not afraid of water (better water stability than emulsified asphalt).

　　（3）优点沥青用量低（通常2.0%~2.8%），比乳化沥青节省20%~30%成本。早期强度较高，养生时间短。水稳定性好，适用于多雨地区。

　　(3) Advantages: Low asphalt usage (usually 2.0%~2.8%), saving 20%~30% cost compared to emulsified asphalt. Early intensity is high, and the duration of health preservation is short. Good water stability, suitable for rainy areas.

　　（4）缺点需要专门的沥青发泡设备（一般拌和站可配发泡模块）。对旧料级配和细料含量敏感，配合比设计要求高。温度低于10℃时发泡效果变差。

　　(4) The disadvantage requires specialized asphalt foaming equipment (usually mixing stations can be equipped with foaming modules). Sensitive to the grading of old materials and the content of fine materials, with high requirements for mix design. The foaming effect deteriorates when the temperature is below 10 ℃.

　　（5）适用场景高等级公路基层或下面层，尤其是重载交通路段、多雨地区。

　　(5) Suitable for the grassroots or lower layers of high-grade highways, especially for heavy traffic sections and rainy areas.

　　四、乳化沥青冷再生——温柔的多面手

　　4、 Emulsified asphalt cold recycling - a gentle and versatile hand

　　（1）原理：水包油的“乳液”乳化沥青是热沥青在高速剪切下，分散到含有乳化剂的水溶液中形成的油水两相体系，外观像咖啡加奶后的乳白色液体。它可以在常温下与旧料拌和。拌和后，水分逐渐蒸发，或者与旧料表面的钙离子等发生化学反应，导致破乳——沥青微粒重新聚并、成膜，裹覆在集料表面。同时，通常也会加入少量水泥或矿粉作为活性填料，吸收水分、调节破乳速度。

　　(1) Principle: Oil in water "lotion" emulsified asphalt is an oil-water two-phase system formed by dispersing hot asphalt into aqueous solution containing emulsifier under high-speed shear, and its appearance is like milky white liquid after coffee and milk. It can be mixed with old materials at room temperature. After mixing, the water gradually evaporates or reacts chemically with calcium ions on the surface of the old material, leading to emulsion breaking - the asphalt particles re aggregate and form a film, coating the surface of the aggregate. At the same time, a small amount of cement or mineral powder is usually added as active fillers to absorb moisture and regulate the demulsification rate.

　　（2）关键特点对旧料要求：对细颗粒要求比泡沫沥青宽松，但旧料含水量控制在5%以内。强度形成：以沥青粘结力为主，水泥水化为辅。早期强度较低，养生时间较长。养生时间：常温下一般需要养生5~14天才能铺筑上面层，否则易出现轮辙。路用性能：柔性较好，变形能力佳，但水稳定性相对泡沫沥青略低。

　　(2) The key features are the requirements for the old material: the requirements for fine particles are looser than those for foam asphalt, but the water content of the old material should preferably be controlled within 5%. Strength formation: mainly based on asphalt adhesion, supplemented by cement hydration. Early intensity is low, and the health preservation time is long. Health preservation time: Generally, it takes 5-14 days of health preservation at room temperature before laying the upper layer, otherwise it is easy to have potholes. Road performance: good flexibility, good deformability, but slightly lower water stability than foam asphalt.

　　（3）优点生产工艺成熟，设备普及率高。与旧料拌和均匀性更好，对旧料含水率和细料适应性更强。施工和易性好，摊铺后表面更密实。

　　(3) Advantages: Mature production process and high equipment penetration rate. Better uniformity of mixing with old materials, stronger adaptability to moisture content and fine materials of old materials. Good construction and workability, with a denser surface after paving.

　　（4）缺点沥青用量较高（通常2.5%~3.5%）。早期强度低，开放交通慢，雨季施工风险大。乳化剂成本较高，低温或高湿环境破乳困难。

　　(4) The disadvantage is that the amount of asphalt used is relatively high (usually 2.5%~3.5%). Early intensity is low, open traffic is slow, and there is a high risk of construction during the rainy season. The cost of emulsifiers is high, and it is difficult to break emulsions in low temperature or high humidity environments.

　　（5）适用场景普通国省干线、低等级公路的基层或下面层，尤其适合旧料品质波动较大、缺乏发泡设备的项目。

　　(5) Suitable for the grassroots or lower layers of ordinary national and provincial highways, as well as low-grade highways, especially for projects with large fluctuations in the quality of old materials and a lack of foaming equipment.

　　五、水泥冷再生——刚硬的大力士

　　5、 Cement cold recycling - a tough strongman

　　（1）原理：纯粹的水化反应水泥冷再生就简单粗暴了：将旧沥青混合料（RAP）+新集料+水泥+水在常温下拌和，依靠水泥水化形成强度。沥青在这里仅仅是“惰性填充物”，不参与粘结作用。实际上，水泥冷再生形成的是一种半刚性基层，与水泥稳定碎石基层类似，只是集料中混入了大量旧沥青混合料。

　　(1) Principle: Pure hydration reaction, cement cold regeneration is simple and crude: old asphalt mixture (RAP)+new aggregate+cement+water is mixed at room temperature, relying on cement hydration to form strength. Asphalt here is only an "inert filler" and does not participate in bonding. In fact, cement cold recycling forms a semi-rigid base, similar to cement stabilized crushed stone base, except that a large amount of old asphalt mixture is mixed into the aggregate.

　　（2）关键特点水泥用量：一般3%~6%，根据目标强度设计。强度形成：纯水泥水化，早期强度高，7天无侧限抗压强度可达2.5MPa以上。养生时间：需覆盖养生7~14天，严禁车辆通行。路用性能：刚度大、承载力强，但容易收缩开裂（温缩、干缩），反射裂缝风险高。

　　(2) Key characteristics: Cement dosage: generally 3%~6%, designed according to the target strength. Strength formation: Pure cement hydration, high early strength, 7-day unconfined compressive strength can reach over 2.5MPa. Health preservation period: It is necessary to cover 7 to 14 days of health preservation, and vehicles are strictly prohibited from passing through. Road performance: high stiffness and strong bearing capacity, but prone to shrinkage and cracking (thermal shrinkage, dry shrinkage), with a high risk of reflective cracking.

　　（3）优点工艺简单，普通稳定土拌和机即可生产。早期强度高，承载力强。对旧料中沥青含量和老化程度几乎无要求。

　　(3) The advantage is that the process is the simplest, and a regular stabilized soil mixer can produce it. High early strength and strong bearing capacity. There are almost no requirements for the asphalt content and aging degree in the old materials.

　　（4）缺点收缩裂缝问题突出，上面层需设较厚的抗裂层。沥青混合料的弹性特征被完全破坏，废旧沥青的“剩余价值”没有发挥。养生期间必须封闭交通，工期长。

　　(4) The problem of shrinkage cracks is prominent, and a thicker crack resistant layer needs to be installed on the upper layer. The elastic characteristics of asphalt mixture are completely destroyed, and the "residual value" of waste asphalt is not fully utilized. During the period of health preservation, transportation must be closed, and the construction period is long.

　　（5）适用场景低等级公路基层、重载交通场站基层，或作泡沫/乳化沥青冷再生的下层补强层。一般不用于高等级公路沥青路面结构层。

　　(5) It is applicable to the base course of low-grade highway, the base course of heavy traffic station, or the lower reinforcing layer of foam/emulsified asphalt cold recycling. It is generally not recommended for use in the structural layer of asphalt pavement on high-grade highways.

　　六、一张表看懂三种技术对比指标泡沫沥青冷再生乳化沥青冷再生水泥冷再生结合料泡沫沥青乳化沥青水泥沥青用量2.0%~2.8%2.5%~3.5%0%水泥用量0.5%~1.5%（辅助）0.5%~1.5%（辅助）3%~6%早期强度中等（2~3天可施工）较低（需5天以上）高（3天可上重型）终强度形成沥青粘结为主沥青粘结为主水泥水化刚度（回弹模量）600~1200MPa500~1000MPa1200~2000MPa抗裂性能优（柔性）优（柔性）差（脆性）水稳定性优良优（但收缩裂缝易渗水）旧料利用率可≥80%可≥80%可≥80%设备要求需发泡装置需乳化沥青生产设备普通拌和设备典型造价中等较高

　　6、 One table to understand the three technical comparison indicators foam asphalt cold recycling emulsified asphalt cold recycling cement cold recycling binder foam asphalt emulsified asphalt cement asphalt consumption 2.0%~2.8% 2.5%~3.5% 0% cement consumption 0.5%~1.5% (auxiliary) 0.5%~1.5% (auxiliary) 3%~6% early strength medium (construction can be carried out in 2~3 days) low (more than 5 days) high (heavy can be carried out in 3 days) final strength forming asphalt bond main asphalt bond main cement hydration stiffness (rebound modulus) 600~1200MPa 500~1000MPa 1200~2000MPa crack resistance excellent (flexible) poor (brittle) water stability excellent (but easy to shrink cracks Water seepage) The utilization rate of old material can be ≥ 80%, ≥ 80%, ≥ 80%. The equipment requires foaming equipment, emulsified asphalt production equipment, and the typical cost of ordinary mixing equipment is medium high and the lowest

　　七、怎么选？记住这三个原则

　　7、 How to choose? Remember these three principles

　　（1）看等级和交通量

　　(1) Check the level and traffic volume

　　高速、一级公路：优先选择泡沫沥青冷再生，兼顾强度与抗裂。二级及以下公路：三种都可，经济性上可考虑水泥冷再生，但必须加抗裂层。

　　High speed and first-class highway: cold recycling of foam asphalt is preferred, and both strength and crack resistance are considered. Second level and below highways: All three types are acceptable. Economically, cement cold recycling can be considered, but a crack resistant layer must be added.

　　（2）看气候和工期

　　(2) Check the climate and schedule

　　多雨地区、雨季施工：泡沫沥青或水泥冷再生更稳妥（乳化沥青破乳困难）。工期紧、需快速开放交通：水泥冷再生早期强度高，但后期裂缝多；泡沫沥青中等，乳化沥青慢。

　　Construction in rainy areas and rainy seasons: cold recycling of foam asphalt or cement is more stable (emulsified asphalt demulsification is difficult). The construction period is tight and transportation needs to be opened quickly: cement cold recycling has high strength in the early stage, but there are many cracks in the later stage; Foam asphalt is medium and emulsified asphalt is the slowest.

　　（3）看旧料品质

　　(3) Check the quality of old materials

　　旧料细粉多、级配良好：泡沫沥青如鱼得水。旧料潮湿、级配波动大：乳化沥青适应性更强。旧料含泥量高或沥青严重老化：水泥冷再生“不挑食”，但浪费了沥青价值。

　　The old material is rich in fine powder and well graded: foam asphalt is like a fish in water. The old material is damp and the gradation fluctuates greatly: emulsified asphalt has stronger adaptability. High mud content in old materials or severe aging of asphalt: Cement cold recycling is not picky, but it wastes the value of asphalt.

　　八、行业趋势：泡沫沥青正在“出圈”

　　8、 Industry trend: foam asphalt is "emerging"

　　近年来，泡沫沥青厂拌冷再生在江苏、山东、江西等省份的高速公路养护中得到大力推广。原因很简单：它兼具了乳化沥青的柔性和水泥的早期强度，而且更、更省钱。

　　In recent years, foam asphalt plant mix cold recycling has been vigorously promoted in highway maintenance in Jiangsu, Shandong, Jiangxi and other provinces. The reason is simple: it combines the flexibility of emulsified asphalt with the early strength of cement, and is more environmentally friendly and cost-effective.

　　以G30连霍高速为例，采用粗粒式泡沫沥青冷再生铺筑基层12千米，两年跟踪检测显示，路面无任何反射裂缝，弯沉值稳定，效果优于传统半刚性基层。

　　Taking G30 Lianhuo Expressway as an example, 12 kilometers of base course is paved with coarse grained foam asphalt cold recycling. Two years of tracking tests show that the pavement has no reflective cracks, and the deflection value is stable, which is better than the traditional semi-rigid base course.

　　而水泥冷再生因为裂缝通病，在高等级公路中的应用正逐步收缩，更多用于底基层或低等级道路。

　　Due to the common problem of cracks, the application of cement cold recycling in high-grade highways is gradually shrinking, and it is more commonly used in subbase or low-grade roads.

　　乳化沥青冷再生则在城市道路、园区道路等对扬尘和气味敏感的工程中仍有独特优势（泡沫沥青在发泡时会有短暂沥青烟）。

　　Cold recycling of emulsified asphalt still has unique advantages in urban roads, park roads and other projects that are sensitive to dust and smell (foam asphalt will have temporary asphalt smoke when foaming).

　　九、写在

　　9、 Write at the end

　　厂拌冷再生不是“一招鲜”，三种技术各有千秋。选对了，废料变好路；选错了，后期裂缝、水损坏让你头疼不已。在做技术决策前，一定要做旧料性能检测和配合比验证试验。没有的技术，只有合适的方案。

　　Factory mixed cold recycling is not a "one trick", each of the three technologies has its own advantages. Choosing the right one, waste becomes a better path; Choosing the wrong one, cracks and water damage in the later stage will give you a headache. Before making technical decisions, it is necessary to conduct performance testing of old materials and mix proportion verification tests. There is no best technology, only the most suitable solution.

　　本文由 冷再生机 友情奉献.更多有关的知识请点击 http://www.tclqgc.com/ 真诚的态度.为您提供为的服务.更多有关的知识我们将会陆续向大家奉献.敬请期待.

　　This article is a friendly contribution from the cold recycling machine For more related knowledge, please click http://www.tclqgc.com/ Sincere attitude To provide you with comprehensive services We will gradually contribute more relevant knowledge to everyone Coming soon.