# Wing Wall Construction Guide | Design Considerations

## Introduction

Wing walls are structural members of structures such as bridges, culverts, and retaining walls. It plays a very important role in civil engineering, providing support and stability to structures.

Wing walls are also known as abutment walls, which are built on either side of a main structure to redirect or retain earth and water flow.

Before we discuss the details of the wing wall construction, let us see some basic terms of wing wall construction.

## Functions of Wing Wall

A wing wall serves as lateral support to the main structure like a bridge, or culvert by absorbing the pressure and weight exerted by the surrounding earth or water.

Wing walls are generally constructed by making some angles. It is not necessary wing wall to be angled. It can be curved or straight, depending on the specific project requirements.

To retain the earth bank of approaches (return wing wall). Approaches are the length of the communication route affected by the layout and design of the bridge at both ends which carry the communication route to the level of the bridge floor.

Proper design and construction of the wing wall play very important roles to ensure the stability and durability of the entire structure.

## Types of Wing Wall

1. Straight Wing Wall (This wing wall is constructed straight along the abutment of a bridge or culvert.)
2. Splayed Wing wall (This wing wall is constructed by making some angle with the abutment of a bridge or culvert)
3. Return wing wall (This wing wall is constructed perpendicular to the abutment of the bridge or culvert)

## Design Considerations for Wing Wall Construction

In order to design a safe, durable, and economical wing wall for a structure, several design considerations must be taken into account. They are given below.

a) Structural Analysis and Load Calculations:- Firstly structural analysis and load calculations should be carried out to calculate the load carrying capacity and different types of loads applied on the wing wall during the life of the wing wall.

b) Soil Testing:- To know the soil properties like bearing capacity, compaction, and drainage characteristics, soil testing should be done to select the proper type and size of the foundation.

c) Geometry of wing wall:- Now according to structural analysis of the construction site and soil condition the shape and size of the wing wall height, angle, length, and curvature should be decided.

d) Material Selection:- Proper selection of materials like concrete mix, stone, or brick should be done which provide proper strength and durability for the wing walls.

## Step-by-Step Guide to Wing Wall Construction

• Site Preparation and Excavation
• Reinforcement Placement
• Formwork Installation
• Concrete Pouring
• Curing Process

### a) Site Preparation and Excavation

First of all clear the construction site by removing any debris or vegetation. And then, excavate the foundation trench according to the design specifications and design country codes.

### b) Reinforcement Placement

After that place steel reinforcement bars (rebars) according to design. The amount of rebar should be provided according to the load, bending moment, and shear force acting at different parts of the wing wall. Reinforcement should be provided sufficiently to strengthen the wing walls and prevent cracking.

### c) Formwork Installation

Install formwork for the foundation and superstructure to provide the required shape of the wing walls before pouring concrete. The formwork should have a smooth and uniform finish toward the concrete pouring side.

### d) Concrete Pouring

Pour high-quality concrete mix into the formwork of the foundation and superstructure to be strong enough to bear loads on it till the design period. Ensure that it fills all spaces and covers all the reinforcement adequately.

Concrete should be compacted properly by the use of a vibrator for concrete to be durable and strong enough to bear the load. Over-compaction may cause segregation and bleeding in concrete structures.

### e) Curing Process

After pouring concrete, cure the concrete to keep it moist and protected from extreme weather conditions for at least 24 days to 28 days. Curing of concrete should be started within 24 hours of casting or according to the mix design of the concrete.

Curing is the process of spreading water on the newly prepared concrete to allow hydration and gain proper strength.

### f) Finishing Touches

After the completion of concrete work and curing for some days, remove the formwork and perform any necessary finishing touches, such as smoothing the surface with cement mortar or slurry or adding any texture.

## Some FAQs (Frequently Asked Questions)

1. Q: What is the purpose of wing wall construction in bridge or culvert?

Ans:- Wing walls in bridge construction are provided to provide lateral support to the structure and retain earth by preventing soil erosion and improving the overall stability of the structure.

2. Q: How much should be the depth of the foundation of the wing wall for a bridge or culvert?

Ans:- The depth of the foundation of wing walls depends on various factors like soil properties, wall height, and the load which will act in the future due to static and dynamic traffic on the structure.

An ideal depth of foundation is provided by a geotechnical engineer according to the site condition and the nature of the soil.

3. Q: Can wing walls be constructed using materials other than concrete?

Ans:- Yes, besides concrete, materials like stone and brick can be used for wing wall construction. The strength of the wing wall to be constructed depends on several factors like design periods, load on it, site condition, environmental impact, etc.

4. Q: Are wing wall construction necessary for culverts or small bridges?

Ans:- Yes, wing walls are essential for culverts and small bridges because they prevent soil erosion around the structure by managing water flow below the structure.

5. Q: Can wing walls be built with a curved design?

Ans:- Yes, wing walls can be constructed with curved designs. Wing walls are generally constructed curves when dealing with specific site conditions or aesthetic considerations.

6. Q: How do wing walls prevent water-related damage to structures?

Ans:- Wing walls redirect water flow away from the main structure like bridges and culverts. It helps to prevent soil erosion. It reduces the risk of water-related damage like chemical attack, and seepage, and enhances the durability of the construction.