The application of cast-in-place foam concrete in my country was initially focused on building roofs and ground energy-saving insulation projects. However, with the gradual increase in awareness of the excellent properties of this material in other fields, its application The scope of application is rapidly expanding, and its application in my country’s municipal roads, underground structures, port water conservancy, mine backfill and other projects is increasing year by year.
Municipal road projects
(1) New road construction projects
Foam concrete is mainly used in soft soil embankments, bridgehead embankments, platform backfills, etc. in new road construction projects. Utilizing the lightweight properties of foam concrete to build embankments in deep soft soil areas can effectively reduce the additional stress on the base, reduce the subgrade settlement, and control the subgrade settlement within the allowable range; when used in bridgehead embankments, it can reduce the friction between the bridge and the bridgehead subgrade. The settlement is poor, providing more comfortable driving conditions; in the back filling project of the retaining wall platform, the lightness and self-reliance of foam concrete can be used to reduce the lateral pressure of the retaining wall and reduce the wall thickness of the retaining wall. The size of the retaining wall reduces the bearing capacity requirements of the foundation.
(2) Road reconstruction and expansion projects
Foam concrete is generally used in road reconstruction and expansion projects The roadbed of high-grade roads in soft soil areas is widened, and the lightweight nature of foam concrete is used to reduce the settlement difference between the new roadbed and the old roadbed.
(3) Road maintenance and repair projects
In road maintenance and repair projects, foam concrete has its own With its advantages of lightness, fluidity, durability and ease of construction, it can be used for embankment slip control, bridge head jump control, foundation void area control, pipe culvert foundation disease control, abandoned pipeline backfilling, etc.
Underground engineering
In urban underground engineering, the lightweight nature of foam concrete can serve as a compensation foundation It can reduce the additional stress on underground structures and ensure the safety of engineering structures. For example, in underground tunnel projects, the tunnel structure design requires that the overlay soil load must be within the range that the structure can bear. If the actual overlay soil load exceeds the structure’s bearing capacity, the overlying fill soil must be reduced in load. Replacement with cast-in-place foam concrete is much simpler and more convenient than re-reinforcement of the underground tunnel structure, and the cost is low, with obvious technical and economic advantages.
Port water conservancy project
Using foam concrete as the port gravity wharf retaining wall material can not only It meets the anti-slip stability requirements of the top surface of the foundation bed, and can also meet the anti-overturning stability requirements of the front toe of the retaining wall. At the same time, the base stress of the foam concrete retaining wall is smaller. For foundations with smaller bearing capacity, larger retaining walls Has good applicability. In water conservancy project revetment wall heightening and reinforcement projects, foam concrete has recently become a popular choice for backfill materials behind the wall. It takes full advantage of its small bulk density, high strength, fast construction speed, and simple construction to effectively reduce the impact of the backfill on the revetment. The load on the wall minimizes the impact of the heightening and reinforcement treatment on the revetment wall.
Filling project
In civil engineering projects, for some small underground spaces, such as building foundation pits and The surrounding gaps of underground pipeline projects have become a major difficulty in project construction because humans and machines cannot operate or the working space is too small to backfill densely. Taking advantage of the advantages that cast-in-place foam concrete can be pumped by hoses, the pouring construction site occupies very little space, has high fluidity during pouring, can be solidified after pouring, and does not require mechanical rolling or vibration, backfilling these special voids can be It achieves the effect of simple construction and dense backfilling, which provides a new technical means to solve the problem of cavity backfilling.
The cast-in-place foam concrete is used to fill the mine goaf, giving full play to the special effect of foam on fluidity, so that the filling has high solidification rate, high filling rate and high top connection The obvious advantage of efficiency can significantly improve the filling efficiency and the quality of the filling body. These advantages enable cast-in-place foam concrete technology to be widely used in the fields of filling mining and old goaf filling and treatment projects. </p