Back to ER Diagram
Survey & Land

Survey & Land Logic

Topographic survey data, survey points, land boundary management, setting out, level surveys, and as-built surveys.

PostgreSQL
6 Tables
Schema: survey
Survey Points

Overview

Survey & Land module manages all surveying activities for construction projects. Topographic survey data establishes baseline terrain. Setting out transfers design coordinates to ground. Level surveys monitor earthwork quantities. Land boundary records establish project limits. As-built surveys document final construction versus design. Survey data integrates with BIM and project progress tracking.


Topo Survey

Setting Out

Level Survey

As-Built

Report
6
Survey Tables
GPS/TS
Instruments
cm
Accuracy
3D
Coordinate System

Status States

StatusDescriptionAllowed ActionsNext States
PlannedSurvey scheduledMobilize EquipmentIn Progress
In ProgressSurvey team on groundCollect DataProcessing
ProcessingData being processed and validatedGenerate ReportCompleted
CompletedSurvey report finalizedShare, Archive

Database Schema

survey.survey_data

  • survey_id — PK
  • project_id — FK → project.project
  • survey_type — topographic | setting_out | level | as_built
  • survey_date, surveyor — Execution details
  • instrument_type — total_station | gps_rtk | drone_lidar
  • accuracy_class — first_order | second_order | third_order
  • status — Planned → In Progress → Completed

survey.survey_point

  • point_id — PK
  • survey_id — FK → survey.survey_data
  • point_number, easting, northing, elevation — 3D coordinates
  • description — Point feature description
  • coordinate_system — UTM | local grid

survey.land_boundary

  • boundary_id — PK
  • project_id — FK → project.project
  • boundary_type — project_limit | phase | zone
  • coordinates_json — GeoJSON polygon
  • area_sqm, perimeter_m — Computed dimensions
  • survey_id — FK → survey.survey_data

survey.as_built_survey

  • asbuilt_id — PK
  • project_id, activity_id — FK references
  • design_coords_json, actual_coords_json — Design vs As-built
  • deviation_mm — Measured deviation
  • within_tolerance — Boolean compliance flag

Survey Operations

1

Topographic Survey

Initial terrain survey establishes existing ground levels. Total station and GPS used for point collection. Data processed into DTM (Digital Terrain Model).

2

Setting Out

Design coordinates transferred to ground using total station. Reference points established with concrete pillars. Grid marked for foundation/structure layout.

3

Level Survey

Progressive level surveys during earthwork to measure cut/fill quantities. Cross-sections at regular intervals. Volume computed using prismoidal method.

4

As-Built Survey

After construction, survey actual positions of structures. Compare with design coordinates. Deviations documented for record and handover.

Survey Queries

Earthwork Volume

SELECT sd.survey_date,
       SUM(CASE WHEN sp.elevation > design_level THEN cut_volume ELSE 0 END) AS total_cut,
       SUM(CASE WHEN sp.elevation < design_level THEN fill_volume ELSE 0 END) AS total_fill
FROM survey.survey_data sd
JOIN survey.survey_point sp ON sp.survey_id = sd.survey_id
WHERE sd.project_id = :project_id
  AND sd.survey_type = 'level'
GROUP BY sd.survey_date;

Validation Rules

Business Rules

  • Coordinate System: All surveys must use consistent coordinate system and datum
  • Tolerance Check: As-built deviations beyond tolerance flagged for rectification
  • Instrument Calibration: Survey instruments must have valid calibration certificate
  • Point Density: Minimum point spacing per survey type (e.g., 5m grid for topo)

Integration Points

Connected Modules

  • Project: Survey progress linked to project activities
  • BIM: Survey data feeds BIM model for terrain and as-built
  • Estimation: Earthwork volumes feed BOQ quantity verification
  • Quality: As-built surveys verify construction accuracy

Best Practices

Recommended

  • Establish permanent benchmark network before construction starts
  • Back up survey data daily to cloud storage
  • Use drone surveys for large-area progress monitoring
  • Maintain survey instrument calibration log