The choice of concrete materials, cement should try to use low hydration heat, long cementing time, preferred in the heat of Portland cement, low heat slag Portland cement, volcanic ash Portland cement. Coarse aggregate should be used continuous grading, fine aggregate should be used in the sand, additives should be used retarder, water reducing agent, admixture should use fly ash, slag powder and so on. Construction of the template requirements. Template support in the construction should be ground before the soil to deal with to ensure that the pole support in the construction will not subsidence. Templates and support the selection must be calculated, in addition to meet the strength requirements must also have sufficient rigidity and stability; side support pole and wall spacing should not be greater than 300mm, the middle should not be greater than 800mm. Before the concrete pouring, quality control personnel should be required according to the specification of the template support, size, etc. one by one inspection, in the demolition of the mold, the concrete strength should meet the requirements of the specification. When these tensile stress exceeds the crack resistance of concrete, it will produce cracks. Many internal changes in the humidity of the concrete are small or slow, but the surface humidity may vary greatly or drastically. Such as poor maintenance, when dry and wet, the surface shrinkage shrinkage by the internal concrete constraints, but also often lead to cracks. compaction of soil in construction when was the first asphalt road made asphalt maintenance systems nottingham old asphalt pavement maintenance