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APPLICATION FOR MEMBERSHIP IN THE UGANDA INSTITUTION OF PROFESSIONAL ENGINEERS (UIPE) TO THE CLASS OF MEMBER AND REGISTRATION WITH ENGINEERS REGISTRATION BOARD (ERB) TECHNICAL REPORT ON DESIGN REVIEW OF SOROTI MOROTO LOT 1 AND LOT 2 (150) AND CONSTRUCTION SUPERVISION OF SOROTI MOROTO LOT 1 PROJECT (...

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APPLICATION FOR MEMBERSHIP IN THE UGANDA INSTITUTION OF PROFESSIONAL ENGINEERS (UIPE) TO THE CLASS OF MEMBER AND REGISTRATION WITH ENGINEERS REGISTRATION BOARD (ERB)

TECHNICAL REPORT ON DESIGN REVIEW OF SOROTI – MOROTO LOT 1 AND LOT 2 (150.3KM) AND CONSTRUCTION SUPERVISION OF SOROTI – MOROTO LOT 1 PROJECT (100.0KM)

REPORT

SUBMITTED BY GEOFFREY NSUBUGA BSc Civil Engineering Email: [email protected] DECEMBER 2017

Technical Report

EXECUTIVE SUMMARY Uganda National Roads Authority (UNRA) is implementing An In-house supervision team to perform. I was deployed on the Upgrading of Soroti - Moroto Road in December 2016 to carryout Design Review and Construction supervision for Soroti – Akism and Akisim - Moroto as a Materials Engineer until procurement of the Supervision Consultant was completed. At the project start up brief, major challenges were identified like omission of swamp treatment by the design consultant, inadequate bridge foundation studies, Natural sands with high silt content and black cotton soils along most sections of the project. A design review was done to eliminate the challenges identified at the start-up of the construction process. Swamp treatment was determined using rock fill, Crushed Rock blinding and a geotextile membrane, crusher run sand was tested and conformed to sand requirements. The Alignment was resampled at intervals of 500m to identify soils unsuitable for road bed preparation as outlined in Clause…………. Additional boreholes were drilled at bridge locations to qualify foundation design parameters. The excavation method was adopted for swamp treatment, unsuitable black cotton soils replaced with a layer of G7 material and compacted to 95% MDD. The unit rates for swamp treatment components were established by the Applicant under the supervision of the Resident Engineer. Dynamic Cone Penetrometer and Dynamic Lightweight Penetrometer were performed by the Applicant to establish subsurface characteristics for pipe and box culverts respectively considering the depth under foundation influence. The applicant obtained control samples and instructed Field Density Tests on all constructed fill and pavement layers to establish conformance to the specifications. During Construction, field site trials were performed for subbase, base and surface dressing to establish performance and optimisation.

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Technical Report

DECLARATION I declare that the content presented in this technical report is a record of my active participation and involvement with significant degree of responsibility on the upgrading of Soroti - Moroto Road Project as a Materials and Pavement Engineer for the design review and construction supervision. The technical content is my interpretation and understanding of engineering facts.

........................................................................ Geoffrey Nsubuga Materials Engineer (UNRA)

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Technical Report

ACKNOWLEDGEMENT I express my sincere gratitude to the Directorate of Network Planning and Engineering for granting me an opportunity to work with the UNRA Construction and Supervision Team on the Construction Supervision of Soroti – Moroto Project Lot 1 and 2 as a Materials Engineer.

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Technical Report

TECHNICAL REPORT TABLE OF CONTENTS Chapter

Description

Page

EXECUTIVE SUMMARY

ii

1

BACKGROUND

1

1.1

Introduction

1

1.2

Introduction (THE PROJECT)

1

1.3

Background of the project

1

1.4

Civil Works Contract

1

1.5

Consultancy contract

2

1.6

Project location

2

1.7

Topography and Climate

3

1.8

The Project Organogram

3

MATERIALS INVESTIGATIONS

5

2.1

Subgrade soil investigations

5

2.2

Prospection for Construction Materials

6

2.3

Subbase Materials

8

2.4

Hard Rock

8

2.5

Water Sources

9

2.6

Sand

9

2.7

Swamps along the Project Route

10

2.8

Swamp Locations

10

2.9

Geotechnical Investigations along Swamps

11

2.10

Additional Swamp Investigations

11

2.11

Settlement Characteristics of the swamps

11

2.12

Swamp Treatment Method

12

2

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Technical Report

3

2.13

Excavation method

12

2.14

Displacement Method

12

2.15

Quantity of Rock fill

13

2.16

Geotechnical investigations at bridge and major box culvert locations

13

2.17

Foundation Parameters

15

PAVEMENT EVALUATION

17

3.1

Subgrade Classification

17

3.2

Traffic Loading

18

3.3

Assessment of Past Traffic Estimates

18

3.4

Present traffic counts

18

3.5

AXLE LOAD DATA

20

3.6

Origin and Destination Surveys

23

3.7

TRAFFIC GROWTH RATES

23

3.8

Traffic forecast

25

3.9

Design Traffic Loading

25

3.10

PAVEMENT STRUCTURE

26

3.11

Design Consultant’s Proposed Pavement Structure

26

3.12

Revised Pavement Structure at Tender Stage

27

3.13

Pavement Design Review.

27

3.14

AASHTO DESIGN (Structural Number Method)

28

3.15

Proposed Pavement Structure

29

Figure 9: Urban Pavement Cross section

30

Figure 10: Urban Cross section

30

4

3.16

Surface Treatment

30

3.17

Chippings for Surface Dressing

31

3.18

Bitumen Specifications

31

3.19

Tests on Aggregates and Bitumen

31

SURFACE DRESSING DESIGN

32

4.1

Design of Spray rates

32

4.2

Design of Spread rates

34

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Technical Report 4.3 5

6

Prime Coat (MC30)

35

CONSTRUCTION SUPERVISION

36

5.1

Introduction

36

5.2

Drainage Inventory

36

5.3

Maintenance of the Existing Road

37

5.4

Site Clearance

37

5.5

Borrow pit Acquisition and Exploitation

38

5.6

Earth Works

38

5.7

Swamp Treatment

39

5.8

Quarry Rock and Operation

39

5.9

Concrete Production and Materials

40

5.10

Concrete Mix Designs

41

5.11

Culverts Crushing Test.

42

5.12

Tests on Bituminous Materials

43

5.13

MC-30 Cut back for Priming

45

5.14

Steel Reinforcement bars

45

5.15

Challenges encountered during Testing of Materials

45

5.16

Pavement layers of Natural gravel material

46

5.17

Stabilisation-Mechanical Modification (Subbase G 30)

46

5.18

Crushed Aggregate Road Base

48

5.19

Challenges for Earth Works and Pavement Layers Construction

48

5.20

Surface Dressing

48

5.21

Field trials for surface dressing

49

5.22

Field Observations

52

5.23

Traffic Management and Control

53

ENVIRONMENTAL MANAGEMENT

54

6.1

Introduction

54

6.2

Potential Impacts of the Project

54

6.3

Mitigation Measures

55

6.4

Monitoring and Supervision

55

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Technical Report 7

8

9

PROJECT RISK MANAGEMENT

56

7.1

Introduction

56

7.2

Risk Identification

56

7.3

Risk Assessment, Analysis and Mitigation Measures

56

CONCLUSION, RECOMMENDATIONS & CHALLENGES

62

8.1

Conclusions

62

8.2

Challenges

64

REFERENCES

66

APPENDICIES

67

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Technical Report

LIST OF FIGURES Description

Page

Figure 1: Project Location ....................................................................................................................... 3 Figure 2: Project Organogram ................................................................................................................ 4 Figure 3: Proposed 3 span bridge ......................................................................................................... 14 Figure 4: Proposed single span bridge ................................................................................................. 14 Figure 5: Classification of Predominant Clay Types ............................................................................. 15 Figure 6: Traffic Counts Stations ..........................................................................................................19 Figure 7: Axle Load Set up at Television ( Mbale - Soroti Road)......................................................... 21 Figure 8: Pavement Evaluation Soroti - Akisim(0+000 –150+300) Analysis 1 ..................................... 29 Figure 9: Urban Pavement Cross section ............................................................................................. 30 Figure 10: Urban Cross section ............................................................................................................ 30 Figure 11: Common Slump Forms ........................................................................................................ 41

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LIST OF TABLES Description Page Table 1: Sections with Unsuitable Soils for roadbed Preparation ............................... 5 Table 2: Borrow Pit Locations identified by Design Consultant .................................. 6 Table 3: Borrow Pit Locations and Materials Quality .................................................. 7 Table 4: Hard Rock Sources ...................................................................................... 8 Table 5: Chemical Test Results ................................................................................. 9 Table 6: Identified Sand Deposits ............................................................................ 10 Table 7: Summary of Swamp Details ....................................................................... 10 Table 8: Summary of Swamp Consolidation Parameters ......................................... 12 Table 9: Provisional Quantities of Rock fill ............................................................... 13 Table 10:Typical Properties of Clay Types ............................................................... 15 Table 11: Foundation Proposals .............................................................................. 17 Table 12: Summary of Classified Traffic Counts along the route (2010) in the most trafficked lane ........................................................................................................... 18 Table 13: Soroti - Moroto Directional ADT Traffic. .................................................... 19 Table 14: Moroto - Soroti Directional ADT Traffic ..................................................... 20 Table 15: Vehicle Equivalent Factors on projects with the area ............................... 22 Table 16: Traffic growth scenarios ........................................................................... 24 Table 17: Demand Elasticity of Petrol and Diesel .................................................... 24 Table 18: Pavement Design Life Selection............................................................... 25 Table 19:Summary of 15 Year Design Cumulative ESA’s........................................ 25 Table 20:Subgrade Classification ............................................................................. 27 Table 21: Proposed Pavement Structure ................................................................. 29 Table 22:Weighing factor for the 1st Seal chippings ................................................ 32 Table 23:Adjustment factors for spray rates (1st seal) ............................................. 33 Table 24:Weighing factor for the 2st Seal chippings ................................................ 33 Table 25:Adjustment factors for spray rates (2st seal) ............................................. 33 Table 26: Designed Spray and Spread rates for surface dressing ........................... 35 Table 27: Tests results for Cement. ......................................................................... 40 Table 28: Problems Encountered while testing materials ......................................... 46 Table 29: Proportions of G30 Material...................................................................... 46 Table 30:Labour mobilised for the trial Construction ................................................ 47 Table 31:Equipment at km 68+000 .......................................................................... 47 Table 32: Equipment at the borrow pit at km 68+300 RHS. ..................................... 47 Table 33: Challenges during the Construction of Earth Works and Pavement Layers ................................................................................................................................. 48 Table 34: Designed Spray and Spread rates for surface dressing ........................... 51 Table 35: Designed Spray and Spread rates for surface dressing ........................... 52 Table 36: Challenges encountered during surface dressing Construction ............... 52 Table 37: Challenges during the Construction of Earth Works and Pavement Layers ................................................................................................................................. 53 Table 38:Risk identification and analysis matrix ....................................................... 58 Table 39:Lessons Learned from Design Review and Supervision ........................... 62 Table 40: Challenges and Actions Taken on the Project. ......................................... 64 x

Technical Report

LIST OF ABBREVIATIONS UNRA : Uganda National Roads Authority MoWT : Ministry of Works and Transport ADT : Average Daily Traffic AADT : Average Annual Daily Traffic BC : Base Course CESAs : Cumulative Equivalent Standard Axles DBST/ DSBS :Double Bituminous Surface Treatment/Double Seal Bituminous Surfacing DCP : Dynamic Cone Penetration ESA : Equivalent Standard Axles ESAL : Equivalent Standard Axle Loads MoWHC : Ministry of Works, Housing and Communications ORN-31 : Overseas Road Note 31 UBOS : Uganda Bureau of Statistics DC : Design Consultant

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1

BACKGROUND

1.1

Introduction

This document is the applicant’s summarised technical report on design review of Soroti – Akisim (Lot 1) and Akisim – Moroto (Lot 2) and construction of Soroti – Akisim (Lot 1). This is presented to demonstrate the applicant’s technical and professional competence. The first four chapters have been prepared to highlight the Applicant’s contribution in the in the materials, pavement and Geotechnical design review of the project road. Chapters five, six and seven cover my experience during the ongoing construction of the Soroti – Akisim road project lot 1. 1.2

Introduction (THE PROJECT)

1.3

Background of the project

The Government of Uganda (GOU) earmarked funds for the National Roads Development and Maintenance Programme (NRDMP), and it intends to apply part of the funds towards payments under the contract for upgrading to bituminous standard of the Soroti – Moroto Road (150.3km) from Gravel to Paved (Bituminous) standard. The Soroti-Moroto road provides an important link in the national road network and contributes significantly to the economic prosperity of northeast region. The road upgrading will also assist the administrative and social coverage in the region, reduce vehicleoperating costs and improve social services and trading opportunities. The road has been regularly affected by the floods during spells of heavy rains due to the low-lying nature of the terrain and a series of seasonal and permanent swamps along the route. The road was a gravel road of class C, in a poor condition; the overall riding quality being rated as unsatisfactory on most of the road stretches. The project starts at Arapai (Teso College) to Nadunget (Moroto). The route traverses districts of Soroti, Amuria, Katakwi and Napak joining the completed Nakapiripit – Moroto road at Nadunget junction. 1.4

Civil Works Contract

Consequently, Uganda National Roads Authority (UNRA) acting on behalf of the GOU, awarded Contract No. UNRA/WORKS/2015-16/00002/002 for the upgrading of the Akisim Moroto Road lot 2 (50.3km) to China Railway No.3 Engineering Group and Contract No. UNRA/Works/2015-16/00002/001 for the upgrading of Soroti – Akisim Lot 1(100km) to China Communication Construction Company with a commencement date of 1st November 2016. The value of the Civil Works Contracts are as listed in the table below:

Section

Contractor

Lot 1 Lot 2

CCCC CR3

Contract Sum 348,000,000,000 248,069,399,126

Duration (Month) 36 30

Technical Report The contract payments are broken into 75% payable in USD and the remaining 25% in UGX. These project sums are inclusive of all the local taxes. This is a pre These are pre –financed contracts with the following conditions to be achieved in the first year of construction. Section Lot 1 Lot 2

Physical progress 30% 30%

Accumulated IPC sums USD 30,000,000 USD 16,000,000

The project road is an earth road to be upgraded to a class II Standard paved road comprising of a carriageway width of 7.00m and shoulder width of 1.5m. The carriageway and shoulders to have a double surface dressing. 1.5

Consultancy contract

There was a delay in the procurement of the Consultancy services for both lot 1 and 2. To keep in line with the intended ...