Engineering Surveys for Highway Alignment: Objectives, Conventional and Modern Methods || Highway Engineering #7

Introduction

Engineering surveys are an essential part of the process of designing and building highways. These surveys provide the necessary data and information to determine the alignment, profile, and cross-section of a highway, as well as the location and design of any related structures, such as bridges and drainage systems. In this article, we will explore the objectives of engineering surveys for highway alignment, as well as the conventional and modern methods that are used to collect and analyze this data.

Objectives of Engineering Surveys for Highway Alignment

The primary objective of engineering surveys for highway alignment is to determine the most appropriate location for a highway based on a variety of factors, including topography, geology, hydrology, ecology, and land use. Other objectives may include:

Determining the location of existing infrastructure, such as utilities, that may need to be relocated or protected during construction

Identifying any potential environmental or cultural resources that may be impacted by the proposed highway

Assessing the potential for landslides, floods, or other natural hazards that may affect the design and construction of the highway

Identifying the most efficient and cost-effective route for the highway

Conventional Methods of Engineering Surveys

The conventional methods of engineering surveys for highway alignment include:

Topographical Surveys: Topographical surveys are used to create a detailed map of the terrain, including elevations, contours, and natural and man-made features. This information is used to determine the most appropriate alignment for the highway and to design the highway profile and cross-section.

Geotechnical Surveys: Geotechnical surveys are used to investigate the subsurface conditions of the proposed highway alignment, including soil type, rock type, and groundwater levels. This information is used to design foundations, slopes, and other features of the highway.

Hydrological Surveys: Hydrological surveys are used to assess the potential impact of the proposed highway on water bodies and drainage systems, including rivers, streams, and wetlands. This information is used to design bridges, culverts, and other drainage structures.

Environmental Surveys: Environmental surveys are used to assess the potential impact of the proposed highway on the natural environment, including wildlife, habitats, and ecosystems. This information is used to design mitigation measures such as wildlife crossings and to identify any cultural resources that may be impacted by the highway.

Modern Methods of Engineering Surveys

In recent years, advances in technology have led to the development of a number of modern methods of engineering surveys for highway alignment, including:

LiDAR Surveys: LiDAR (light detection and ranging) is a remote sensing technology that uses laser beams to create detailed 3D maps of the terrain. This information can be used to create detailed topographical maps and to identify potential hazards, such as landslides or rockfalls.

GIS Surveys: GIS (geographic information systems) is a technology that is used to collect, store, and analyze spatial data, including data from various sources such as satellite imagery, aerial photography, and ground-based surveys. This information can be used to create detailed maps and to assess the potential impact of the proposed highway on the natural and built environment.

Drone Surveys: Drone surveys are used to collect aerial imagery and data using unmanned aerial vehicles (UAVs). This information can be used to create detailed topographical maps and to identify potential hazards, such as landslides or rockfalls.

Conclusion

In conclusion, engineering surveys are an essential part of the process of designing and building highways, as they provide the necessary data and information.