| 护坡砖使用过程中裂缝产生的成因以及预防措施 |
| 添加时间：2018/11/10 9:51:39 浏览次数： |
| 我国的社会经济水平的不断提高，对于水利水电的基础建设上极为看重，水电站、水利护坡等都逐渐的增加，护坡砖模具的使用越来越频繁，在通过使用护坡砖模具浇筑成型的护坡砖在使用一段时间护坡砖砖体会产生一定的裂缝。 With the continuous improvement of social and economic level in China, great importance has been attached to the infrastructure of water resources and Hydropower projects. With the gradual increase of hydropower stations and hydraulic slope protection, the use of slope protection brick moulds has become more and more frequent. The use of slope protection brick moulds has resulted in some cracks in the use of slope protection brick moulds for a period of time. Sew. 在浇筑护坡砖过程中所产生的裂缝主要是因为：由于混凝土在硬化过程中，水泥和水起化学反应，产生大量的水化热引起混凝土的温度上升，如果热量不能很快散失，内部和外部温差过大，就将产生温度应力，使结构内部受压，外部受拉。混凝土在硬化初期，只有很低的抗拉强度，如果由内外温度差引起的拉应力超过混凝土早期抗拉强度时，混凝土就要产生裂缝。 Cracks in the process of pouring revetment bricks are mainly caused by the chemical reaction between cement and water during the hardening process of concrete, which results in a large amount of hydration heat, which causes the temperature rise of concrete. If the heat cannot be quickly lost and the temperature difference between inside and outside is too large, the temperature stress will be produced, which will make the internal structure compressed. External tension. In the early stage of hardening, concrete has very low tensile strength. If the tensile stress caused by temperature difference between inside and outside exceeds the early tensile strength of concrete, concrete will crack. 而对于这种事情的发生所能避免的措施主要是：尽量选用低热或中热降低泥矿渣水泥、粉煤灰水泥；减少水泥用量，将水泥用量2尽量控制在450kg/m以下；降低水灰比，一般混凝土的水灰比控制在0.60以下；改善骨科级配，掺加粉煤灰或高效减少水剂等来减少水泥用量，降低水化热；改善混凝土的搅拌工艺，采用“二次风冷”新工艺降低混凝土的浇筑温度；在混凝土中掺加一定量的具有减水、增塑、缓凝等作用的外加剂，改善混凝土拌和物的流动性、保水性，降低水热化，推迟热峰出现的时间；合理安排施工工序，分层、分块浇筑，以利于散热，减小约束；在大体积混凝土内部设置冷却管道，通过冷水或冷气冷却，减小混凝土的内部温差；加强混凝土温度的监控，及时采取冷却保护措施；加强混凝土养护，混凝土浇筑后，及时用湿润的草帘、麻片等覆盖，并洒水养护，适当延长养护时间，保证混凝土表现缓慢冷却，在寒冷季节，混凝土两面必须采取保温措施，以防寒潮袭击。 The main measures to avoid such occurrence are as follows: choosing low or medium heat to reduce the cement content of mud, slag and fly ash; reducing the cement content to control the cement content below 450kg/m; reducing the water-cement ratio to control the water-cement ratio below 0.60; improving the orthopaedic gradation and adding powder. Coal ash or water additives can reduce the amount of cement and the heat of hydration, improve the mixing technology of concrete, adopt the new technology of "secondary air cooling" to reduce the pouring temperature of concrete, and add a certain amount of additives with water reducing, plasticizing and retarding functions to improve the fluidity of concrete mixtures. Water-retaining, reducing water-heating, delaying the time of hot peak; reasonable arrangement of construction procedures, layered and block pouring, in order to facilitate heat dissipation and reduce constraints; setting cooling pipes in large volume concrete, cooling by cold water or air, to reduce the internal temperature difference of concrete; strengthening the monitoring of concrete temperature, timely mining Take cooling protection measures; strengthen concrete maintenance; after concrete pouring, cover it with wet curtains, flakes, etc. in time, and sprinkle water to maintain it. Appropriately prolong the maintenance time to ensure slow cooling of concrete. In cold season, thermal insulation measures must be taken on both sides of concrete to prevent cold wave attack. 还有便是在使用期间内，有些护坡砖的使用在一些迎水面上，水温的冷热交替极为容易发生水泥制品的裂纹产生，所以为了减少裂纹的产生在对护坡砖塑料模具浇筑过程中所使用的水泥最好采用能抗冻性较好的，以免冷热交替下护坡砖发生裂缝从而导致水泥砖块产生裂缝导致最后护坡砖破损难以在继续使用。 In addition, during the use period, some slope protection bricks are used on some water-facing surfaces. The alternation of cold and hot water temperatures is extremely prone to cracks in cement products. Therefore, in order to reduce the cracks, the cement used in the process of plastics mould casting of slope protection bricks should have better frost resistance, so as to avoid the alternation of cold and hot. Cracks occur in downhill slope protection bricks, which lead to cracks in cement bricks, resulting in failure of the final slope protection bricks, which is difficult to continue to use. |
| 上一页 护坡砖模具 |
| 下一页 河道护坡砖机在具体操作时需要注意以下流程 |