Concrete Mattress

I. Product Introduction

Concrete mattress originated from European companies that extensively developed concrete pads in the 1980s. Originally made from concrete cured in prefabricated plastic tanks interconnected with the rope, commonly referred to abroad as concrete pads. It provided the industry with a low-cost permanent solution to the problem of protecting the pipeline and the stability of the environment near the pipeline. Today, after the polypropylene rope is laid, concrete is poured on top and plastic tanks are no longer used. Concrete mattresses are mainly used for the laying of underwater flexible rows, all of which are ballasted by concrete mattresses with good integrity, strong ability to adapt to riverbed deformation, easy construction, etc. They have been widely used in river and estuary bottom protection projects around the world, and have achieved good economic and social benefits.

II. Application Design

The concrete mattress is mainly made of concrete such as small square, non-equal rectangular block, equal round disc type block, equal upper and lower double ladder type block and single flexible concrete mattress of reinforced concrete long prism type. Generally it uses anti-aging polypropylene rope linkage. It can be prefabricated by professional manufacturers, transported to the construction point by ship, and installed and constructed by lifting ship or laying ship.

Some companies have special treatment on the edge of the concrete mattress (such as enlargement, weight gain) can greatly enhance the stability of the edge, reducing the concrete mattress in the construction and application of the rolled-up situation.

According to the characteristics of the concrete mattress can be divided into conventional concrete mattress and single flexible concrete mattress. Conventional concrete mattress is mostly made of plain concrete members, and single flexible concrete mattress is a kind of concrete mattress that can only be bent singly, made of prismatic columns made of reinforced concrete, which can be used to act as a load dispersing support. It is also an ideal choice for applications in soft soil bearing.

Ⅲ. Main Advantages

The main competitors of concrete mattress are sand-ribbed flexible rows. Sand-ribbed flexible rows are mainly made of geotextile, reinforced tape, and long pipe bags of sand ribs. Although sand ribs are very cost effective, deployment can sometimes be problematic depending on the location of the project or pipeline. Compared to concrete pads, it may involve more speculative extrapolation in design deployment and thus there is more potential for movement or failure to achieve desired results and thus errors. Concrete mattresses are very stable in comparison, both in terms of size wear consumption after laying and in providing stable protection from the pipeline seabed environment.

In addition, if disassembly is required, for example in the case of pipeline inspection, the bags must be removed and replaced one by one. Changing bags is also not always a permanent solution, as they are not as stable as concrete mattress and run the risk of not holding their shape.

IV. Application Scenarios

Concrete mattress is mainly used for the laying of underwater flexible row, the main role is to protect the river bed within the laying area or to protect the cable pipeline from corrosion. When used in river-related projects, it can achieve the purpose of protecting the bottom, protecting the foot, preventing panning and brushing, protecting the foundation of the project, and thus protecting the stability of the upper solid structure.

There are two main types in concrete mattress applications.

1. submarine and near-shore pipeline fixed: divided into a single layer of gland and the upper cover under the mat two forms. In the case of more stable underwater foundation usually use single layer gland. The use of top cover and bottom pad can effectively eliminate the erosion under the pipeline. When the soil below the pipeline is at risk of eroded, the concrete mattress of the lower gland can be used to provide effective lower environmental protection and stability to stop the erosion of the pipeline from the lower environment.

2. Embankment slope protection and river and pier substrate protection: The earliest application of this product was probably in the 1930s, when it was used for flood control and erosion protection along the Mississippi River in New Orleans, USA. In 2012, the New Orleans branch of the U.S. Army Corps of Engineers again applied concrete mattress to the river to maintain channel stability and prevent diversions.

Concrete mattress has been widely used around the world, such as in the second phase of the Yangtze River deep water channel management project, the dredging promotion dike project used a large number of concrete mattress bottom protection structure. In the deep water channel construction of Yangtze River Nanjing Phase I bottom protection project also has a large number of applications. Many construction and design experiences have been gained in the concrete mattress laying project, which has improved the construction efficiency. Practice has proved that concrete mattress has unique advantages and good effects and wide application in submarine and river engineering project.