INWED Engineering Heroes: Amal Hajj Ali

INWED Engineering Heroes: Amal Hajj Ali


Associate, Head of the Materials Unit at Dar’s GHCE Department

1. What first motivated you to choose the Materials Field? And what keeps you in this field today?

To start with, I always thought about a field where “creativity” is the most prominent feature and criterion for selection. At the time, I believed that would only be available in an art career. Actually, because of that, I first thought of studying graphic design but luckily, I chose civil engineering. During my studies, I came to discover the “hidden art” behind almost all material involved under civil engineering projects related to bridges, roads, airports, tunnels, harbours, dams, etc.

During my 4th year at the university, I was inspired by my Professor who used to teach us geotechnical and foundation design and who showed us the importance of this domain and highlighted the diversity and distinctiveness in it. I still remember him saying “You have to taste soil to understand geotechnical engineering”. I decided to do my final year project in this topic, and the research work I did was really interesting and so I realized that this is the domain which I should seek as my career.

Then, I joined the Geotechnical and Heavy Civil Engineering (GHCE) Department at Dar where I was first supporting, then leading, the Construction Materials Unit within the department. This gave me the chance to contribute to several challenging major projects in infrastructure, roads and building domains and to experience and recognise the diversity and the innovations in this field.


2. Your scope on projects is generally described as preparing investigation programs and specifying, reviewing and controlling the materials for various building and infrastructure projects. How do you decide what types of investigations are needed and which materials are to be used? What do those investigation programs generally include and why are they so very important?

Investigation programs and material specifications, whether required for building or Infrastructure projects, are essential for foundation design of structures, pavement design for road projects, concrete mix designs, earthworks, and assessment of borrow areas.

Selecting the right material is of extreme importance and constitutes an integral part of the construction process and in-service performance of any structure. It is essential to obtain actual information on the physical and chemical characteristics of the founding terrain (soil/rock), groundwater levels, and/or on the existing pavement structural layers. In fact, inadequate investigations or relying on assumed parameters are commonly some of the primary causes of ground and pavement failures.
To prepare geotechnical or pavement investigations, I first do a thorough desk study to obtain deep insight of the project conditions, and I check available data from previous investigations and studies in order to adequately plan and optimise the number of boreholes that need to be drilled under the various structures, their location, and depth and/or on the test pits that have to be excavated along a road alignment or light structures as well as on preparing the required field and laboratory testing to determine the properties of the material.

Site reconnaissance visits are also important for proper planning of the investigation program. Site investigations form the basis for defining, and correlating the main design parameters to ensure adequate quality and safety for the project and for the feasibility of the construction process.


3. You are also often responsible for reviewing and providing recommendations on construction material submittals. Has this approach changed recently, with the stronger focus on sustainability, environment, and health? What are some of the ways in which geotechnical engineers contribute to creating more sustainable buildings?

My role at Dar stimulated me to significantly contribute in evaluating construction material and assessing the availability of suitable material within project vicinities in order to optimise construction cost and avoid transporting materials over long distances.

I always seek alternative solutions to treat unsuitable materials and encourage sustainable approaches such as the use of by-products, recycled materials, reclaimed asphalt material, and/or construction material modification/stabilization should it be in earthworks, pavement structures and other infrastructure and building structures.

Elsewhere, I evaluate new construction alternatives in the pavement. These alternatives can include, for example, the rubblization of concrete pavement to speed construction and reduce the use of virgin aggregates. For the design, construction and maintenance of new pavement structures as well as for pavement rehabilitation, lifecycle cost analysis is also considered to check the overall costs including maintenance interventions and environmental impact over the lifecycle of the pavement. Such measures will assist in reducing the pollution rate, carbon footprint, embodied energy and emissions to achieve sustainable design.

4. At Dar, you’ve worked on hundreds of projects of various sizes including major airports, ports, strategic bridges and highways, and infrastructure for new developments. How does your scope of work differ from one project to the other? What are some things these projects have in common? Which types of projects have you found most challenging and which are the most rewarding?
Since the majority of our projects require input from a material engineer, I have the opportunity to contribute to more than 100 projects every year, including major and high scale infrastructure and building projects.

Each project has its own challenges, especially with regard to preparing geotechnical designs and specifying materials. Ground is naturally variable and not easily predictable, and this makes geotechnical design more challenging compared to other engineering fields in which the quality and design can be defined with great precision and confidence. Moreover, each project has its particular formations, ground and groundwater conditions, environmental conditions, local market practice, etc., all of which have significant influence on the project’s design approach.

So, proper identification and interpretation of field data is crucial to developing ground models and engineering parameters that are representative and robust, notwithstanding the intrinsic variabilities and uncertainties in the subsurface. Still, projects with problematic soils such as reclaimed soil, soft and compressible clay, collapsible soils, hazardous waste, and unstable material are considered the most challenging. Thankfully, I have been highly exposed to various projects/markets and case studies with different challenges, approaches, and experiences throughout my career. This has helped me build solid expertise in the field, and I can reflect that expertise on ongoing projects, predicting common practice problems and recommending suitable and cost-efficient solutions for each potential issue.


5. What are some of the trends that you are excited about?

Digitisation, automation, and global databases are the trends we are currently intensely focused on. My GHCE colleagues and I are gathering our know-how in the field, and transforming our practice through a more digital approach. Digitisation, automation, and BIM are our new tools. I see in this transformation a promising future and a chance for our know-how to make a bigger impact on the market.


6. Finally, what would be your advice to a girl thinking of a future as a geotechnical/material engineer?

Geotechnical/materials engineering is an exciting field that is much different from other civil engineering divisions. Here, the engineer is literally playing in the dirt with rocks and materials in her hands. This field has no routine, and every new project triggers new sorts of challenges. My advice to new female graduates who are seeking a career in geotechnical engineering is to show confidence and interest in their work, to build gradual experience though the challenges that they will face, to keep on learning and exploring innovative methods, to think out of the box and come up with solutions to the problems, and finally to love their career.