Precast Drain vs Cast-in-Situ Drain in MiTS

Drain is a channel or structure designed to remove surface or subsurface runoff from a developed area into the water bodies nearby such as rivers, seas, etc. Designing a drainage system, engineers can choose between precast drains or cast-in-situ drains, considering factors such as,

1.  Cost-effectiveness

2. Site-specific requirements

3. Complexity of the shape and sizing

What is a precast drain? #

A precast drain is a type of drainage system structure made from concrete, manufactured off-site, typically in factories, under a controlled environment by suppliers.

The process of manufacturing a precast drain starts with the preparation of the mold that has been reinforced properly, followed by pouring of the concrete mixture into the molds and the curing process. Then, the finished structures will be transported to the construction site which will then be installed at the designated location, and connected to other drains or components of the drainage system designed.

With the precast method, the drain structures offered are more versatile in a way that the mold can be customized in various shapes and sizes to meet the requirements of a project. Other than that, precast drains manufactured in the factories also provide better quality control with consistency in the production standards and environment maintained for the perfect concrete curing process.

What is a cast-in-situ drain? #

Cast-in-situ drains also involve pouring of mixture onto molds of specific form and curing properly for a durable drain structure, but the entire process takes place on-site. It involves excavating trenches and lining them with formwork or molds in the desired drain locations.

In such cases, cast-in-situ drains offer more flexibility in adapting to the complexity of the terrain, particularly when considering variations in height that correspond to the depth of the excavated trenches. Furthermore, with drains created on-site, the connections are more seamless and continuous without the need for joints which can be the potential weak points to the drainage system.

Applying Precast or Cast-in-situ drains in MiTS #

Drain types in MiTS #

Within MiTS, users are presented with variety of drain type to select from, catering to their specific project needs. This selection encompasses both precast and cast-in-situ drains.

Options > Project Parameters > Expand Drainage > Expand Drain types > Click on any of the drain types for the dimensions

Differentiating between Precast and Cast-in-situ drains in MiTS #

Customization of drain height in MiTS stands out as a prominent distinction between the precast and cast-in-situ drains.

In the context of precast drains, engineers have the ability to precisely determine and maintain a consistent height, which makes them particularly suitable for projects that necessitate uniformity. This feature is prominently showcased in the software through the editable height options available in the Dimension Editor under Spread Input or Project Parameters. The ‘height’ of precast drains is a variable dimension that can be effortlessly modified to increase the drain capacity without affecting the width dimension.

On the other hand, cast-in-situ drains exhibit height variations following the depth excavated, that is based on Ground Level – suitable Invert Level of the drain. Hence, why, users are not able to change the height computed by the software.

Users may refer to the list below to further understand the difference between the two types of drains in MiTS.

Cast-in-situ drain #

Half-round drain #

Block drain #

Precast drain #

Box Drain #

V-Shape Drain #

Trapezoid Drain #

U-Drain #

U-Drain with Dry Weather Flow (DWF) #