UHPC超高性能混凝土作為一種新型的水泥基復(fù)合材料，被稱為不開裂的混凝土，它一般采用高強(qiáng)硅酸鹽水泥、硅灰、石英粉、細(xì)硅砂、減水劑、有機(jī)纖維等多種高強(qiáng)度韌性材料經(jīng)過特殊工藝配置而成的高性能纖維增強(qiáng)混凝土。最初被應(yīng)用于廣東英德北江四橋，使橋梁結(jié)構(gòu)有效避免連續(xù)箱梁橋自重過大、主跨過度大的梁體開裂等難題。

UHPC ultra-high performance concrete, as a new type of cement-based composite material, is known as non cracking concrete. It is generally made of high-strength Portland cement, silica fume, quartz powder, fine silica sand, water reducing agent, organic fiber and other high-strength toughness materials through special process configuration to form high-performance fiber reinforced concrete. Originally applied to the Beijiang Fourth Bridge in Yingde, Guangdong, the bridge structure effectively avoids problems such as excessive self weight and cracking of the main span of continuous box girder bridges.

除應(yīng)用于大跨徑橋梁箱梁橋面鋪裝外，還被廣泛應(yīng)用于建筑結(jié)構(gòu)加固、工程搶修，例如港口碼頭的防腐蝕防水構(gòu)筑物的保護(hù)以及石油海洋行業(yè)中鋼結(jié)構(gòu)建筑的保護(hù)層防護(hù)。UHPC超高性能混凝土之所以被稱為不開裂的混凝土是因?yàn)樗趯?shí)際應(yīng)用中可以有效的防止結(jié)構(gòu)出現(xiàn)裂縫，從材料本身來說，孔隙率低，不含粗骨料，通過提高材料內(nèi)分子的細(xì)度和活性，讓它在使用過程中的高韌性得以發(fā)揮，相比較于普通的混凝土來說更不容易產(chǎn)生開裂的現(xiàn)象。材料經(jīng)過700次抗凍融實(shí)驗(yàn)后仍然完好，抗折強(qiáng)度能是普通混凝土的10倍以上，抗折強(qiáng)度高，也是使材料柔韌性更好的一大因素。

In addition to being used for the pavement of large-span bridge beams and box girder decks, it is also widely used for building structural reinforcement and engineering repair, such as the protection of anti-corrosion and waterproof structures in port terminals and the protection layer protection of steel structure buildings in the oil and marine industry. The reason why UHPC ultra-high performance concrete is called non cracking concrete is because it can effectively prevent structural cracks in practical applications. From the material itself, the porosity is low, and it does not contain coarse aggregates. By improving the fineness and activity of molecules in the material, its high toughness can be exerted during use, making it less prone to cracking compared to ordinary concrete. After 700 freeze-thaw tests, the material remains intact, with a flexural strength that is more than 10 times that of ordinary concrete. Its high flexural strength is also a major factor in improving the flexibility of the material.

其次這種超高性能混凝土的抗壓強(qiáng)度也比普通混凝土的抗壓強(qiáng)度要高，甚至比常見的生鐵的抗壓強(qiáng)度還要高，普通混凝土的抗壓強(qiáng)度在15到30兆帕左右，超高性能混凝土的抗壓強(qiáng)度超高性能混凝土的抗壓強(qiáng)度一般在150兆帕左右，是普通混凝土抗壓強(qiáng)度的10倍以上。

Secondly, the compressive strength of this ultra-high performance concrete is also higher than that of ordinary concrete, and even higher than the compressive strength of common pig iron. The compressive strength of ordinary concrete is around 15 to 30 megapascals, while the compressive strength of ultra-high performance concrete is generally around 150 megapascals, which is more than 10 times the compressive strength of ordinary concrete.

再有這種超高性能混凝土材料本身自重輕，是混凝土建筑結(jié)構(gòu)的三分之一，自重的減少能夠有效的降低靜荷載，更利于建造那種細(xì)長(zhǎng)型的建筑物，例如在預(yù)應(yīng)力橋梁上應(yīng)用這種混凝土，能夠有效降低預(yù)應(yīng)力鋼筋的使用率，降低材料成本，節(jié)省工程項(xiàng)目費(fèi)用。

Furthermore, this ultra-high performance concrete material itself has a light weight, which is one-third of the weight of concrete building structures. The reduction in weight can effectively reduce static loads, making it more conducive to building slender buildings. For example, applying this type of concrete to prestressed bridges can effectively reduce the usage rate of prestressed steel bars, reduce material costs, and save project costs.

因此超高性能混凝土被廣泛應(yīng)用于建筑、橋梁、隧道、水港碼頭和道路等多個(gè)領(lǐng)域。例如，裝配式建筑中，UHPC幕墻、圍墻、集成屋；水庫(kù)大壩護(hù)坡工程；高速路防撞墻；橋梁鋪裝；地鐵景觀裝飾等。UHPC超高性能混凝土應(yīng)用如此廣泛那么它如何施工呢？材料攪拌：超高性能混凝土在攪拌時(shí)應(yīng)按照廠家推薦的加水量進(jìn)行攪拌，宜采用臥軸、行星式或逆流強(qiáng)制式攪拌機(jī)攪拌，攪拌時(shí)間不得少于2min，也不得超過3min。

Therefore, ultra-high performance concrete is widely used in various fields such as construction, bridges, tunnels, water ports, docks, and roads. For example, in prefabricated buildings, UHPC curtain walls, walls, and integrated houses; Reservoir dam slope protection project; Highway collision walls; Bridge paving; Subway landscape decoration, etc. How to construct UHPC ultra-high performance concrete when it is widely used? Material mixing: Ultra high performance concrete should be mixed according to the recommended amount of water by the manufacturer during mixing. It is recommended to use a horizontal axis, planetary or counter flow forced mixer for mixing, and the mixing time should not be less than 2 minutes or more than 3 minutes.

材料澆筑：材料入模前應(yīng)根據(jù)設(shè)計(jì)要求用專業(yè)的設(shè)備檢測(cè)超高性能混凝土的相關(guān)數(shù)值，合格后方可入模澆筑，澆筑時(shí)溫度最好控制在5~30℃，避免高溫或低溫，溫差較大的天氣狀況下澆筑；澆筑時(shí)自由落體高度不能大于2米，大于2米時(shí)，應(yīng)采用溜槽、串聯(lián)關(guān)油缸、漏斗等輔助輸送材料，不能出現(xiàn)分層和離析的現(xiàn)象；澆筑時(shí)應(yīng)分層連續(xù)進(jìn)行，間隔時(shí)間不得超過90分鐘，不得隨意留施工縫；振動(dòng)施工：可使用振動(dòng)設(shè)備如插入式振動(dòng)棒、附加平面振動(dòng)器、表面平面振動(dòng)器等可用于振動(dòng)超高性能混凝土。養(yǎng)護(hù)說明：不僅僅是需要及時(shí)澆水保濕，還要注意控制混凝土的溫度變化。在濕養(yǎng)護(hù)的同時(shí)，應(yīng)保證混凝土表面溫度與內(nèi)部溫度和所接觸的大氣溫度之間不出現(xiàn)過大差異。

Material pouring: Before the material is poured into the mold, professional equipment should be used to test the relevant values of ultra-high performance concrete according to the design requirements. Only after passing the test can it be poured into the mold. It is best to control the temperature during pouring at 5-30 ℃ to avoid pouring in high or low temperature weather conditions with large temperature differences; When pouring, the free fall height should not exceed 2 meters. When it exceeds 2 meters, auxiliary conveying materials such as chutes, series closing oil cylinders, funnels, etc. should be used to prevent layering and segregation; During pouring, it should be carried out layer by layer continuously, with an interval of no more than 90 minutes, and construction joints should not be left arbitrarily; Vibration construction: Vibration equipment such as plug-in vibration rods, additional plane vibrators, surface plane vibrators, etc. can be used to vibrate ultra-high performance concrete. Maintenance instructions: It is not only necessary to water and moisturize the concrete in a timely manner, but also to pay attention to controlling the temperature changes of the concrete. During wet curing, it should be ensured that there is no significant difference between the surface temperature of the concrete and the internal temperature, as well as the atmospheric temperature in contact.