General Job Description  
  Specific Job Descriptions  
  Operational Plan  
  Rules and Regulations  
  Operational Procedures  
  Active Tenders  
  Online Documents  
  RHD News  



RHD Operational Procedure Technical Services Wing
BRRL - Soil Investigation Division
OP/BRL/2.2 - Defect Investigation and Management
Purpose and Scope :

This procedure outlines the process to be adopted following a request to BRRL to investigate a major defect in an existing road.
Definitions :

Defect - is deemed to include excessive settlement of a road pavement together with both embankment and cut slope failures.

Defect Investigation Report - includes the results of all field and laboratory tests deemed necessary to determine the cause of a defect, together with an analysis of those results and recommendations for remedial action to repair the defect.
Responsibility :

Superintending Engineer - BRRL (SE-BRRL) - has overall responsibility for services undertaken or provided by BRRL.

Executive Engineer - Soil Investigation Division (EE-SID) - has overall responsibility for the management and conduct of defect investigations including both field and laboratory tests on samples and interpretation of results.

Executive Engineer - Material Testing & Maintenance Division (EE-MTMD) - is responsible for the laboratory testing of field samples from road pavements and interpretation of results.

Sub - Divisional Engineer - Soil Investigation Division (SDE-SID) - is responsible for the soil investigations on site and subsequent laboratory analysis of samples together with the preparation of the interpretive report for review by EE-SID.
Method :


Almost all requests for defect investigations will come from the Zones, and such requests must be made to SE-BRRL by the relevant ACE for the Zone or SE for the Circle in which the defect is located. Since the investigation and subsequent remedial works will take some time to implement, it will be the responsibility of the SE for the Circle to ensure that site of the defect is made safe and does not present a hazard to the public.


Following receipt of a request for a defect investigation SE-BRRL will instruct EE-SID to undertake an initial site visit to make a visual assessment of the likely cause of the defect, and an estimate of the field and laboratory tests that would need to be carried out to prepare a Defect Investigation Report.

As part of this report EE-SID will prepare a programme for the investigation together with a budget estimate for any external costs that will be incurred, and will submit these to the originator of the request for them to obtain budget approval from CE-RHD.


Following budget approval to undertake the defect investigation EE-SID will arrange for the field investigations in accordance with OP/BRL/2.1. Where the defect takes the form of severe deformation of a comparatively new road pavement, as part of the field investigations samples may need to be taken from the pavement layers for subsequent laboratory analysis to determine compliance or otherwise with the original pavement design.

At completion of the field and laboratory tests EE-SID, in conjunction with EE-MTMD as appropriate, will prepare a report on all tests carried out and an interpretive report based on an analysis of the results.


In parallel with the preparation of the interpretive report on test results EE-SID will prepare a Defect Investigation Report summarizing the results of the interpretive report forming conclusions as to the cause of the defect. The Defect Investigation Report will also make specific recommendations how to rectify the defect and general recommendations on how to avoid similar defects occurring on other road projects.

Upon completion and approval by SE-BRRL the Defect Investigation Report will be sent to the originator of the request by EE-SID, copied to Road Design & Safety Circle and / or Bridge Design Circle if general recommendations are made.

Following this EE-SID will ensure that a copy of the Report is archived within BRRL.
References :

OP/BRRL/2.1 Major Field Soil Investigations
Procedure Flowchart :

The procedure flowchart for this procedure is detailed below -




For duties associated with each grade of personnel see


Updated on : 1/12/2003