IN
DEGREE PROJECT THE BUILT ENVIRONMENT, SECOND CYCLE, 30 CREDITS
STOCKHOLM SWEDEN 2021,
Implementation of a tool for equipment supply planning
Creation and implementation of an Excel tool to improve the efficiency of the planning of supply for equipment in the structural work phase of apartment buildings projects
THÉO BESCH
KTH ROYAL INSTITUTE OF TECHNOLOGY
SCHOOL OF ARCHITECTURE AND THE BUILT ENVIRONMENT
Implementation of a tool for equipment supply planning
Creation and implementation of an Excel tool to improve the efficiency of the
planning of supply for equipment in the structural work phase of apartment
buildings projects
THÉO BESCH
Master’s Programme, Civil and Architectural Engineering, 120 credits
Date: February 24, 2021 Supervisor: Folke Björk
Examiner: Kjartan Gudmundsson
School of Architecture and the Built Environment Host company: Eiffage Construction Habitat
Swedish title: Implementering av ett verktyg för planering för tillförsel av utrustning
Swedish subtitle: Skapande och implementering av ett
Excel-verktyg för att effektivisera planering för tillförsel av utrustning för resning av byggnadsstommen vid byggande av flerbostadshus
Implementation of a tool for equipment supply planning / Implementering av ett verktyg för planering för tillförsel av utrustning
© 2021 Théo Besch
Abstract | i
Abstract
Supply planning is one of the key steps in an apartment building construction project, due to the repetitive nature of these projects where the construction pace therefore has a crucial importance. However, if the working force planning and the materials planning are often acknowledged as important, the equipment supply planning can happen to be considered as secondary.
Therefore less effort has been put in the tools used to make this planning.
This master thesis is the result of a work in collaboration with the methods department at Eiffage Construction Habitat, one of the most important French construction companies. It presents the implementation of a tool that automates an important part of the equipment supply planning in order to gain efficiency during this planning process and to be able to focus deeper on the key issues of the project. This tool allows to drastically reduce the time spent during the supply planning for the equipment of the structural phase, both regarding vertical works (walls and columns) and horizontal works (floors, beams and balconies). Along with making the planning more efficient, it allows to standardize the output documents and facilitate the work of the other departments with whom the methods department collaborates. Resulting from a case study and an internal survey, the implemented tool relies on the Microsoft Visual Basic for Applications technology, allowing to stay within the users’ range of mastered software, therefore improving the adoption potential of the tool. The results analysis showed a great satisfaction from the users, both regarding the abilities of the tool and its form.
Keywords
Construction, Appartment buildings, Equipment supply, Visual Basic for Applications, Planning
ii | Abstract
Sammanfattning | iii
Sammanfattning
Resursplaneringen är ett av de viktigaste stegen i ett projekt för byggande av flerbostadshus på grund av den repetitiva karaktären hos dessa projekt där bygghastigheten därför har en avgörande betydelse. Men om arbetskrafts- planeringen och materialplaneringen ofta ses som viktiga kan planeringen av utrustningsförsörjningen råka betraktas som sekundär. Därför har mindre ansträngningar lagts på de verktyg som används för att göra denna planering.
Detta examensarbete är resultatet av ett arbete i samarbete med metodav- delningen vid Eiffage Construction Habitat, ett av de viktigaste franska bygg- företagen.
Arbetet presenterar implementeringen av ett verktyg som automatiserar en viktig del av planeringen av utrustningsförsörjningen för att få effektivitet under denna planeringsprocess och för att kunna fokusera djupare på de viktigaste frågorna i projektet. Detta verktyg gör det möjligt att drastiskt minska den tid som spenderas under leveransplaneringen för konstruktions- fasens utrustning, både när det gäller vertikala arbeten (väggar och pelare) och horisontella arbeten (golv, balkar och balkonger). Tillsammans med att effektivisera planeringen möjliggör det att standardisera utdata och underlätta arbetet för de andra avdelningar som metodavdelningen samarbetar med.
Till följd av ett studiefall och en intern undersökning är det implementerade verktyget beroende av Microsoft Visual Basic for Applications-tekniken, vilket gör det möjligt att hålla sig till denprogramvara som användarnas har tillgång till och kan behärska, , vilket förbättrar möjligheter för att verktyget ska accepteras och använda verktyget. Resultatanalysen visade en stor tillfredsställelse från användarna, både vad gäller kan leverera och hur gränssnittet till användaren är utformat.
Nyckelord
Byggprocess, Flerbostadshus, Utrustningsförsörjning, Visual Basic for Applications, Planering
iv | Sammanfattning
Résumé | v
Résumé
La planification de l’approvisionnement est l’une des étapes clés d’un projet de construction d’habitats collectifs, en raison du caractère répétitif de ces projets où le rythme de construction a donc une importance cruciale. Cependant, si la planification des effectifs et la planification des matériaux sont souvent reconnues comme importantes, la planification de l’approvisionnement en matériel est parfois considérée comme secondaire. Par conséquent, moins d’efforts ont été consacrés aux outils utilisés pour effectuer cette planification.
Ce mémoire de master est le fruit d’un travail en collaboration avec le département méthodes d’Eiffage Construction Habitat, l’une des plus impor- tantes entreprises françaises de construction. Il présente la mise en œuvre d’un outil qui automatise une partie importante de la planification de l’approvision- nement en matériel afin de gagner en efficacité lors de ce processus de planification et de pouvoir se concentrer davantage sur les enjeux clés du projet. Cet outil permet de réduire drastiquement le temps passé lors de la planification de l’approvisionnement pour le matériel de gros oeuvre, aussi bien en ce qui concerne les ouvrages verticaux (voiles et poteaux) que les ouvrages horizontaux (planchers, poutres et balcons). En plus de rendre la planification plus efficace, il permet de standardiser les documents de sortie et de faciliter le travail des autres services avec lesquels le service méthodes collabore. Issu d’une étude de cas et d’une enquête interne, l’outil implémenté s’appuie sur la technologie Microsoft Visual Basic for Applications, permettant de rester dans le périmètre des logiciels maîtrisés par les utilisateurs, améliorant ainsi le potentiel d’adoption de l’outil. L’analyse des résultats a montré une grande satisfaction des utilisateurs, tant au niveau des capacités de l’outil que de sa forme.
Mots clés
Construction, Habitat collectif, Approvisionnement en matériel, Visual Basic for Applications, Plannification
vi | Résumé
Acknowledgments | vii
Acknowledgments
I would like to thank all the people who helped me with the work on this project and the writing of this thesis.
First, I would like to thank Professor Folke Björk, professor at KTH and supervisor of my thesis, for his help and precious advice during the entire process of the project. Despite the distance, he followed this project with both an expert and a caring eye.
I would like to express my deepest gratitude to Mahmoud Si Youcef and Guilhem Alrang, my two supervisors at Eiffage Construction. Instigators of this project, they were a crucial help for me to grasp its challenges and its issues. Without their enthusiasm and their impressive knowledge of the field, this project couldn’t have been the same. Along with them, I want to thank the entire team of the methods department, whose warm welcome gave me the best work environment I could hope for. Each one of them gave me precious advice without which this project wouldn’t have been possible.
Last but not least, I would like to thank Louise and Augustin, my two roommates, to whom Covid and remote working gave an unexpected importance in the writing of this thesis.
Paris, February 2021 Théo Besch
viii | Acknowledgments
CONTENTS | ix
Contents
1 Introduction 1
1.1 Motivations . . . 1
1.2 Purpose . . . 1
1.3 Goals . . . 2
1.4 Delimitations . . . 3
1.5 Structure of the thesis . . . 3
2 Background 5 2.1 Planning process . . . 5
2.2 Equipment supply planning . . . 6
2.3 Summary . . . 7
3 Research Methodology 9 3.1 Background study . . . 9
3.2 Choice of technology . . . 10
3.3 Evaluation process . . . 11
4 Tool Implementation 13 4.1 Vertical Works Equipment . . . 13
4.1.1 Data collection . . . 13
4.1.2 Needs quantification . . . 14
4.1.3 Executive documents . . . 16
4.2 Horizontal Works Equipment . . . 16
4.2.1 Data collection . . . 16
4.2.2 Needs quantification . . . 17
4.2.3 Executive document . . . 19
4.3 Diverse Security Equipment . . . 20
x | Contents
5 Conclusions and Future work 21
5.1 Results analysis . . . 21
5.2 Conclusions . . . 22
5.3 Limitations . . . 23
5.4 Future work . . . 24
List of acronyms and abbreviations | xi
List of Figures
3.1 Commercial model of the B4/B5 project . . . 10 4.1 Example of a data table for vertical works equipment . . . 15 4.2 Example of a schedule for vertical works equipment . . . 16 4.3 Example of a visual summary for vertical works equipment . . 17 4.4 Example of data tables for horizontal works equipment . . . . 18 4.5 Example of a schedule for horizontal works equipment . . . . 20
List of acronyms and abbreviations
CAD Computer-Aided Design ECH Eiffage Construction Habitat VBA Visual Basic for Applications
xii | List of acronyms and abbreviations
Introduction | 1
Chapter 1 Introduction
1.1 Motivations
Planning is one of the most crucial phases in a construction project, especially in an apartment building project. Indeed, apartment buildings projects show an important repetitiveness in most of their tasks compared to other types of buildings, especially in the superstructure, where most of the floors are quite similar to each other. The main consequence of that repetitiveness is the importance of the pace: the schedule must be perfectly timed because each delay in a task will repeat itself whenever that task is due to be done. Any error in the planning is at least multiplied by the number of floors, and often even more as it has many other consequences and it can derail the whole pace of the project.
Equipment supply is one of the aspects that can often be considered as secondary in the planning but it can be a major source of delay. Indeed, whereas the accent is often put on being sure that the right working force and the right materials are onsite at the right time, the absence of needed equipment can lead to inefficient workers and a paralysis of the works. On the other hand, for both economic and logistic reasons, one can not consider renting equipment with excessive margins to be sure that they always have at least what they need. That’s why the forecast and planning of equipment needs has to be precise enough, both in quantities and in schedule.
1.2 Purpose
One of the biggest challenges of the planning phase is the short amount of time devoted to it. Indeed, it is most of the time made by teams working on many
2 | Introduction
different projects at the same time, with quite short notice. Therefore any lack of efficiency in the planning process will be time lost for the thinking about the construction and planning optimisation. To that end, the automation of the most basic tasks of this planning can be of great help, as they can allow the planner to focus on more sophisticated issues. Apartment buildings projects are really adapted to this process of automation as there often are a lot of common points between two different projects. Automating everything that is related to these common points can therefore free some precious time to focus on specific issues, that will often be key issues upon which will depend the success or not of the project.
1.3 Goals
The goal of this project is to create a tool that maximizes the precision and the efficiency of the equipment supply planning during the structural phase of apartment buildings projects. This has been a request from Eiffage Construction, one of the biggest construction company in France. This project has been run within the methods department of their apartment buildings division,Eiffage Construction Habitat (ECH). The first and most obvious goal of the developed tool is to make the whole process more efficient through automation of the most repetitive tasks within the planning process. However, given its field of use, it must answer to different constraints.
The users of the tool are for the biggest part completely familiar with IT solutions, mainly with desktop tools andComputer-Aided Design (CAD) software. However very few of them are familiar with coding or with more advanced IT solutions. With that in mind, it is crucial for the adoption of the tool that it be completely user-friendly and easy to master.
Another important constraint for the tool is flexibility. Indeed, as two projects are never exactly identical, both in their content and in their working hypotheses, the tool must be able to fit these changes. To do so it is crucial to keep in mind during the whole creation process that any computed value is a suggested value, that can be easily overwritten by the user.
Moreover, the automated aspect of the tool must not dispense the user from the whole process of thinking that is essential to an efficient planning.
The project managers specifically asked that some aspects of the equipment planning shouldn’t be automated even if they technically could because they are critical in the overall understanding of the project progress.
Another goal of the tool is to facilitate the use of the data once the planning is done. Many different interlocutors have use of this supply planning, as the
Introduction | 3
equipment depot, the site managers, the costing department, etc. and each of them need the information under different forms. The tool should therefore take this into consideration and make it easy to generate the documents that will be useful to each of these interlocutors.
There are three main deliverables in this project: the tool itself, an explanatory note on how to use it to make it easily usable for any new user, and a technical explanatory note about the coding, to enable later evolutions of the tool.
1.4 Delimitations
The created tool focuses on the equipment planning during the structural work phase. The methods currently used during the other steps of the planning aren’t concerned by this project. Three categories of equipment are concerned here:
formwork equipment, shoring equipment and security equipment.
1.5 Structure of the thesis
This thesis will first cover the background of the study, by detailing the current planning process in an apartment building project. After a presentation of the different methodological choices, the tool implementation will be described.
The results, conclusions and perspective of future work are then presented.
4 | Introduction
Background | 5
Chapter 2 Background
This chapter provides background information about the current planning process used during the preparation of an apartment building project. It then details the current method used to plan the equipment supply.
2.1 Planning process
The planning process is one of the major phases during the preparation of a project. It consists of various steps that follow a logical order, aiming at the best and most efficient organization of the construction phase. This process helps the constructor to prepare the construction. It can be done by the constructor itself, or by a methods department within the constructor company, or even by an external methods company. The steps are globally the same within each company as they naturally respect the logic of the thinking.
However, how each step is performed can differ between two companies. The quality of the tools that perform these steps is judged both by their accuracy and by their efficiency.
The process starts with establishing the bill of quantities, along with thinking about the construction methods. The construction methods setting consists in deciding how every task of the structural work will be achieved.
For example, it consists of deciding which beam will be pre-made and which will be traditionally cast, which slab will be traditionally cast and which will use shuttering floor. Once this is done, the bill of quantities gathers the quantity of every specific task at every floor. This document is the first base for every planning that will follow.
The second step is the crane pace-loading. In an apartment building project, the rhythm of construction is determined by the ability of the crane to
6 | Background
follow the pace, and the manpower can always be adapted to follow the crane’s pace. Therefore, the goal is that the crane be always fully used throughout the day. To do so, some tools have already come to fruition: from all the tasks of a floor in the quantity of bills, they can compute the time needed for the crane to execute all these tasks as long as the necessary manpower, material and equipment are available. The result of this crane pace-loading is the amount of days needed for each floor.
This then allows to build the schedule of the structural work phase. This schedule is built through a Gantt chart. The primary decomposition of each floor’s tasks is to differentiate the vertical works (walls and columns) and the horizontal works (beams and floors). Each of these tasks will last for the duration computed by the crane pace-loading. The planning associated with the bill of quantities will allow to compute the production rate: the quantity of each type of work that needs to be done everyday. The production rates will be the source of all the supply planning, in terms of manpower, material and equipment.
2.2 Equipment supply planning
As this topic is really company-oriented, it is really difficult to analyze the tools used by different companies as they are not necessarily keen on sharing their planning tools. For that reason, the method presented here is the method currently used within the methods department of ECH, which sought an improvement of their tool.
The global equipment planning process can be split into three main parts:
vertical works equipment, horizontal works equipment and diverse security equipment. Regarding the vertical works, the most important work is to quantify the amount of form panels needed to cast the walls and columns.
Panels of different length and height exist so they need to be chosen in an appropriate manner. As far as the horizontal work is concerned, there are various elements to quantify according to the choices of construction method, but the most common examples are shoring towers, metal props and slab beams. These are usually quantified through ratios to the production rates. The security part is more wide and less repetitive as it depends a lot on the project.
It can regroup equipment such as railings, overhanging work platforms or stair podiums.
The widely used method within the department consists in filling a template table. Something that can be easily noticed is the diversity of the documents used by each person in the department. Almost everyone have their own
Background | 7
template with its own level of automation. Some tools used are basic Excel sheets where the quantities have to be manually computed. There were some attempts of automation through macro programming but none of them is generally used, seemingly for their lack of ergonomics or flexibility. As a result, after both a case study and interviews as later detailed in 3.1, there is definitely room for improvement in this process. The dominant feeling about it is that a considerable amount of time is wasted in formatting and table filling and therefore leaves less time for thinking and optimizing. There is therefore a need for improvement regarding the efficiency of this process, thus the idea of automating parts of it.
2.3 Summary
The whole planning process is a chain of different tasks all connected to one another: construction methods, bill of quantities, crane pace-loading, schedule and finally supply planning. The logic flow between all these steps is crucial to the coherence of the planning and it is primordial to keep that in mind when trying to optimize the process. However every single step can be made as efficient as possible in order to free some time for the delicate matters. Some of them are currently already quite efficient but some show room for improvement. The current process for equipment supply planning, based mostly on filling tables by hand, seems relatively basic and could be considered as archaic. That is why an automation of this process could be able to bring noticeable advancement to the whole chain.
8 | Background
Research Methodology | 9
Chapter 3
Research Methodology
3.1 Background study
The first step of this project was to analyze the current state of the whole planning process and more deeply of the equipment supply planning process in order to point out the weaknesses that need improvement and the challenges that have to be faced. A true understanding of the existing system was necessary to get a good grasp on the real needs of the company. Two methods were chosen for doing this.
The first one was to go through the whole process through a case study.
To do so, we worked on an apartment building project in Asnières-Sur-Seine, called ZAC d’Asnières - B4/B5. This project, represented on figure 3.1, consists in the building of 265 apartments in a student facility, 120 private housing and 85 public housing which construction phase will last two years and a half. Working on the entire planning process from the beginning to the end allowed to weigh the importance of the equipment planning, but also to understand more precisely its inter-dependence with the other steps of the planning. Indeed, it is crucial to deeply understand what information is needed at what time and where it comes from. Moreover, it allowed to get a feeling about the parts of this process being already efficient and the parts being the most important to improve.
This feeling was only personal so the second part of the background study was a survey within the department to make benefit of the knowledge and experience of people who have been working on the topic for a long time and who have more experience and therefore a more precise idea of what they need. Through individual and collective meetings, they shared their opinions about the steps they thought to be efficient and the improvements they’d like
10 | Research Methodology
Figure 3.1: Commercial model of the B4/B5 project
to see. This step allowed to get a more detailed idea of what the tool should look like and what it must help to do. Indeed, plenty of information was drawn from these meetings, about the issues currently faced with the system, and the wishes about the new system.
3.2 Choice of technology
Apart from CAD software, all the steps of the planning process are made through Microsoft Excel and Microsoft Project, including the equipment needs planning. In order to maximize the adoption easiness of the tool, it seemed necessary to remain within this perimeter. Moreover, MicrosoftVisual Basic for Applications (VBA) resources seemed sufficient in order to solve the exposed problems. The use of this tool within Excel therefore seemed the most adapted solution.
There are also other options that could have made the coding more efficient, but the main advantage of MicrosoftVBAwas the interface, both for the user and for potential future improvements or modifications. Regarding the users, it seemed crucial to remain as close as possible to their habits in terms of software use so the Microsoft Excel interface was undeniably the best solution.
Some languages such as Python or Java allow to work with Excel data and with the Excel interface. However the choice of remaining within MicrosoftVBA was made in consideration of potential future modifications. Indeed, using VBAmakes it possible for anyone in the company with some basic knowledge to improve or modify the tool in the future if needs be. Creating this tool
Research Methodology | 11
in another language would have made it a definitive, frozen tool, because nobody in the company would have the time to dive into Python code for a small modification. The risk in producing such a frozen tool would be that as soon as the automated parts don’t fit exactly the needs, the user would rather go back to a fully manual tool, which has the only advantage of flexibility.
3.3 Evaluation process
One of the biggest challenges in this tool implementation was to be sure that it would match the expectations of the operative future users, and that they would adopt it, and not stick with their old habits. To ensure that, the evaluation of the tool was made through continuous feedback and frequent talks with the operatives all along the conception of the tool. These recurrent meetings and talks had major advantages.
The first one is that it is quite hard to establish from the beginning all the functionalities that the tool should have, especially when you start from a fully manual process. For this reason, it occurred many time during the implementation that, when presented with what was already implemented, the users had ideas and suggestions about what else could be done. A part of this process that was very important was the two way dialog about what would be ideal and what would be possible, in order to establish what should be done.
Another goal of these frequent meetings was to be sure that the tool would be used. Indeed, in a such time-tensed sector, any tool that doesn’t perfectly match the user needs and makes them feel like they are loosing time will be immediately put aside and the user will go back to the tools they were using before. Therefore, in order to avoid that all the work dedicated to this project is discarded, it was crucial to be sure that the tool would match the requirements.
12 | Research Methodology
Tool Implementation | 13
Chapter 4
Tool Implementation
The tool and its implementation must follow the same logic that the supply planning process presented in2.2: planning of the vertical works equipment, horizontal works equipment and then security equipment. Indeed, these categories of works require different types of equipment but most importantly their supply planning follows very different logic and reasoning. The structure and form of the supply planning must therefore be different for each of them and adapted to the thought process.
The first step of the tool, which is the only step common to the three categories of equipment is the data extraction from the schedule. Information such as the name of the tasks, their duration, date of beginning and end, and the related quantities is extracted from the project schedule, and is formatted to be then exploitable. From them, a text recognition of the name of the tasks allow the tool to extract them to the right category.
4.1 Vertical Works Equipment
4.1.1 Data collection
The first step of the data collection about the vertical works equipment is information about the project itself. Most of them are collected through user input. The first one is the margin coefficient that the user wants to use in their supply planning, namely the percentage margin that will be taken on all the supply planning in order to prevent from equipment malfunction, or unpredicted needs. This can vary along with the management style of the project managers, but also with the construction site constraints, such as the lack of storage space, or even constraints that can lead to an uneven pace and
14 | Tool Implementation
punctual needs for intense work. A second needed information is the brand of the wall panels that will be used. The reason for which this is needed is that the length of the panels differ according the the brand. For the two brands regularly used within Eiffage projects (Outinord and Hussor), there are three sizes of available panels, multiples of an elementary panel. Outinord offer panels of 62.5, 125 and 250 cm whereas Hussor offer panels of 60, 120 and 240 cm. The chosen brand can therefore have consequences on the equipment planning. The last information is the way the user wants to quantify the need in panels, and there are two possibilities for this. What’s important to understand is that the panels are ordered and delivered as elementary elements (for example 62,5 cm, 125 cm and 250 cm) but on the construction site they will be assembled in packs (from 62,5 cm to 625 cm), and the goal is to keep them as much as possible assembled to avoid to have too many manipulations.
Therefore, the user can choose to quantify their needs in elementary elements, or directly in packs adapted to the pace and the configuration of the project.
Some information is also set by default within the tool but can be modified by the user, such as the size of the panels that will be used for columns casting.
Information about each task is then collected. Most of it comes from the schedule. All the tasks whose name contains a word related to walls of columns is extracted and information about it is collected: the duration, the dates of beginning and end, the quantity of walls and the quantity of columns. The user is then required to input the height of the walls for each task. One task can represent a whole floor, or part of a floor if different height of walls are needed at this floor, or even a group of floors if they all have the same characteristics. There are usually one or two tasks per floor for the infrastructure and one or two tasks for the entire superstructure as one of the main characteristics of apartment buildings if the repetitiveness of the superstructure.
4.1.2 Needs quantification
The specificity of the vertical works equipment supply planning is that a lot of information is needed for each task, but as only one type of equipment is quantified (wall panels), it is the same type of information that is needed for all the tasks. A table to collect and compute all the information for all tasks is therefore the most adapted format. Each row represents a task and follows from left to right the thought process that ultimately leads to the quantification of each type of panel.
The first information computed by the tool is called the panel configuration.
Tool Implementation | 15
Each length of panel is available in different heights: the main panel which is 280 cm high, two bottom-extensions of height 100 cm or 150 cm, and a top-extension of height 50 cm. The panel configuration is the combination of these different elements that matches the better with the needed height for the wall. When the user inputs the height of the wall, the tool therefore finds automatically the first higher panel configuration. However, this choice as every other can be overruled by the user if they want to use another configuration, for example for needs of efficiency if that particular configuration is used for the task just before and for the task just after. The second information computed is the linear need in panels. This is computed from the quantities and durations that give a daily pace, associated with the margin coefficient. Finally, the user must distribute this linear need among the different lengths available. This being done manually was a wish from the operatives, who wanted to force the user to think about the distribution most adapted to the shape of the floor, and not to use a standard distribution. For example, a twisted floor with many corners will require more small panels than a regular rectangle one, even if they have the same daily needs.
Figure 4.1: Example of a data table for vertical works equipment
Once this table has been filled and both the panel configuration and needs quantification have been done, all that information is extracted to a schedule that will allow to manage the deliveries and returns. In this schedule, the tool first sums up the theoretical needs in panels of each height and length for each week. It then computes the needed deliveries and returns by comparing the needs from one week to the one before. The next step is to shift the deliveries to the week before and the returns to the week after. This is due to the fact that there is a packaging delay needed before being able to use the panels and before being able to send then back. This delay is not necessary for a panel shifting from a task to another so it wasn’t possible to simply extend the needs before and after each task. The real needs for each week are then summed up again. During this process, the user can manually add some stored equipment if they want to avoid having too many deliveries and returns. For example
16 | Tool Implementation
if some equipment is supposed to be returned and then delivered again two weeks later, the user can force it to be stored during these two weeks.
Figure 4.2: Example of a schedule for vertical works equipment
4.1.3 Executive documents
The process previously detailed allows to compute the need for each height and each length of panel at any given time. However, what’s important is how this information is formatted and used. To do so, two executive documents are created.
The first one is a visual summary. For each floor and each task, this document sums up all the information about the task and draw a representation of the required panels and their configuration. This document, visible on figure 4.3is to be used by the project managers during the construction.
The second document is a summary of all the deliveries and return, with their dates and contents. This document allows the pricing department to evaluate the costs of the equipment, and the equipment depot to organize the deliveries.
4.2 Horizontal Works Equipment
4.2.1 Data collection
As in the case of the vertical works equipment, the first step of data collection is information about the project itself. However it is definitely more succinct as
Tool Implementation | 17
Figure 4.3: Example of a visual summary for vertical works equipment
only the margin coefficient is needed from the user. Many ratios of quantities of equipment according to the quantity of work are also built-in by default.
Information about each task is also required, and comes from both the schedule and user inputs. As with the vertical works, the duration, date of beginning and end, and the quantity are extracted from the schedule for every task which name contains words linked to horizontal works. For each of these tasks, the user must first input the type of work, which can be a beam, a floor or a balcony. For each of these types of work, the tool then offers different options of construction methods. The frequently used methods for beams are pre-made, traditional casting with shoring towers, and traditional casting with modular formwork. The floors are usually either pre-made, traditional cast with shoring towers, traditional cast with modular formwork or made from alveolar slabs. Regarding the balconies, many options are available as traditional casting with shoring towers, modular formwork, overhanging work platforms or floor tables, or pre-made balconies set thanks to shoring towers, floor tables or mounting brackets.
4.2.2 Needs quantification
The equipment supply planning for horizontal works is really different from the vertical works as many types of works are concerned and therefore many different types of equipment must be quantified. Whereas in vertical works
18 | Tool Implementation
only different sizes of wall panels were quantified, in horizontal works the tool must plan the quantities of almost ten different types of equipment. Moreover, each task has its own needs in equipment. Therefore, the previously used structure of a table with a row per task isn’t adapted at all in this case: each type of work and therefore each task must have its own data table.
Once the user has filled the type of work and construction method for each task, the tool generates automatically one table per task with the needed equipment for that task, and computes the quantities needed from the information about the task and the built-in ratios. The company operatives specifically asked for some quantities not to be automatically computed, to force the user to think about the optimum quantity and not to use a basic ratio. Moreover, all the ratios can be overwritten by the user if they feel that this specific case differs from the average scenario. The same overwriting is also possible with the number of equipped zones, which is also proposed by default. As far as the walls are concerned, the wall panels are only used for one day during the casting process so the quantity of panels needed is the quantity of wall daily built. As far as horizontal elements are concerned, the equipment is needed for several days so at a given moment, the number of equipped structures will be a multiple of the number of daily built structures. The number of equipped zones depends of the type of work but is usually the same from one project to another. However, given the specifics of the project, the user can chose to modify this number and adapt is to the specific project course. Along with certain quantities and the possibility of forcing ratios, the user also has to input the size of some types of equipment as shoring towers and metal props. Indeed, these depends on the heights of the floors where the work is done, and there are many overlaps between the different sizes available so it must be a choice from the user, and can’t be computed.
Figure 4.4: Example of data tables for horizontal works equipment
After all the individual tasks tables that quantify what’s called the rotating equipment (because it moves from one structure to the one next to it, etc.), a table is created for immobilized equipment. This deals with equipment that will remain for a long duration at a specific location and for a specific structure,
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for example a structure that needs to be shored over the whole length of the project. These tasks are usually not mentioned in the project schedule so the user has to fill them manually.
4.2.3 Executive document
The tables used for the needs quantification can be used by the project managers during the construction to be able to monitor where the equipment should be allocated. However, an executive document is needed to be able to order the equipment and evaluate its cost. To do so, a schedule is created where the needs in each equipment are summed up every week. Before generating that schedule, the user can choose to keep some tasks or equipments out of it.
This can be useful if the user wants to plan the supply for certain tasks, but won’t need this planning in the executive documents as theses particular tasks will be subcontracted.
A special problem is visible through the schedule due to the fact that some of the different tasks of the horizontal works happen at the same time (beams and floors for example), whereas the vertical works tasks were strictly successive. Due to this, peaks in the equipment needs can appear: weeks where the quantity is bigger than the week before and the week after. Two reasons can explain these peaks, and one of them needs to be taken care of.
A first reason is the superposition of two different tasks at the same time that require the same equipment. For example, shoring towers might be required at the same time for floors and for beams a bit further at the same floor. Another possibility is that two tasks of the same nature happen during the same week.
The problem then is that that the tool considers them as happening as the same time, whereas in truth they will follow each other, and therefore the quantity of equipment needed that week is not the sum of the needs but the maximum.
This distinction between the two situations could be automated, however the company operatives wished to simply bring light to these peaks and let the user chose how they want to deal with them.
Another important difference with the vertical works is the evolution of the needs through time. As far as walls are concerned, as there is only one type of equipment, the quantities increase and decrease with important bearings between the evolutions. Therefore the needs for deliveries and returns can be identified as the weeks where leaps happen. However with the horizontal works equipment, the evolution is much more continuous, due to the fact that many tasks happen in parallel. Therefore it was decided to simply present the needs at any time and let the project managers, along with the equipment
20 | Tool Implementation
Figure 4.5: Example of a schedule for horizontal works equipment
depot, organize the deliveries and returns as they wished, depending on the storage space available, the distance to the depot, or the budget planned for logistics.
4.3 Diverse Security Equipment
Compared with the vertical works, the security equipment is the other extreme in terms of similarity from one project to another. The number of possible different types of equipment is major, and they can’t be quantified with only figures and quantities as they require blueprints and complex information about the project. Therefore it was decided that regarding this equipment planning, the method of the table template previously used for the whole equipment planning remained the most adapted and the most efficient.
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Chapter 5
Conclusions and Future work
5.1 Results analysis
The evaluation process of the tool followed the same structure as the background study: a case study and dialog with the future users.
Once the tool was finalized, the case study presented in 3.1, a housing project in Asnières-Sur-Seine, was used again as an example of what the tool could offer. We went again through the equipment supply planning of this project, to be able to compare the efficiency and the relevance of the created tool with the previously used methods. The differences in terms of efficiency were undeniable. The time spent in the supply planning was considerably shorter with the tool than the time previously spent during the background study for the same planning. However it was also crucial to be sure that the results were relevant. Indeed, even if all the computed results can be overwritten by the user, it would be a huge loss of time if every one of them had to be overwritten because they didn’t match with what the user had in mind.
The comparison between the default results given by the tool and the manually written results from the original case study showed almost identical results in all the categories of the planning.
The second evaluation of the tool was made through feedback from the future users. As mentioned earlier, the users were consulted all along the implementation of the tool, so the main goal of this final evaluation was to make sure that nothing was left aside. Just as during the whole process, this dialog resulted in step by step modifications until reaching solutions that pleased all the users. Here again, one of the biggest challenges was not only to understand their needs but to accommodate their needs, as every user has their own habits and therefore their own wishes.
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5.2 Conclusions
In 1.3 different goals were set for this tool, and can be divided into two categories: what the tool shall achieve, and what form it should take.
The main goal that was set was to gain efficiency in the equipment supply planning through automation of the most repetitive tasks. This can be considered as well achieved, as with the implemented tool, no work of formatting is needed from the user, and the user inputs are limited to their strict minimum. This can be seen directly in the time spent for an entire supply planning, which is considerably reduced thanks to this tool. Another goal of the tool was to be able to extract uniformed output documents, that match the needs of all the interlocutors of the methods department. This is one of the biggest improvements brought by the tool. Indeed, the previously used method required either the user of their interlocutor to manually extract and format the information they needed from the the entire planing. Both the extraction and the formatting are now managed directly by the tool, that generates different documents, based on the information every other departments usually need, and the format in which they need it.
Along with the goals regarding what the tool should achieve, goals were set about the characteristics it should have in order to ensure the better adoption from the users, and the biggest efficiency in their work. The first and most obvious one was user-friendliness. This is relatively difficult to evaluate on a short-term basis because it would require a lot of testing from different users, so that they are confronted with many different situations. However some first conclusions can be drawn. The software used and the format of the tool ensures an easy adoption as no new software is used and everything stays on a domain that the users already master. The users are already familiar with all the environment of the tool, they therefore only have to focus on where each information goes in the tool. Moreover, the frequent exchanges with the future users during the tool implementation bring two advantages. The first one is that most of them already know how the tool works as they followed its implementation. This won’t help any new user to master it but it ensures that some people within the department master it and have a deep understanding of how it works. The second advantage is that the user implication during the whole process allowed them to express their opinions about the tool format and user-friendliness. Therefore, the tool looks like what the users wanted it to look like, which can be a crucial help for its adoption. Another important characteristic of the tool was its flexibility, and the fact that any computed value or need is only suggested and can be overwritten by the user. This need has
Conclusions and Future work | 23
been deeply taken into consideration and everything can be changed manually by the user. Moreover, in the information categories where it was expected that the user would often want to overwrite them, the implementation allows the user to change the computed value, see easily that the used value is an input and not the computed value, and easily go back to the computed value if they don’t want to overwrite it anymore. The last characteristic of the tool wished by the managers was that the tool wouldn’t prevent the user from thinking about the specifics of the project. The objective of the tool was to get rid of the repetitive tasks and allow the user to focus on the tasks that required thinking, not to allow them to plan the entire supply by just filling boxes and pressing buttons. To ensure that, various strategic choices were made of quantifications that wouldn’t be automated even if they could be, as the automated result would be a generic result and not necessarily fit the specificities of the project. The final case study allowed to realize that the key thinking points noticed during the planning with the previous method remained key thinking points and were not flooded in the automated process.
5.3 Limitations
A few difficulties were met during the tool implementation, and led to limitations in the tool performances.
The first one is the balance that had to be found between the adaptability of the tool to any situation and the wish to have as few user input as possible.
This wish to limit the number of inputs forces the equipment supply planning to stay within the parameter of given scenarios, where a consequent part of the information is default information, common to all projects. The case of pre- made balcony equipment needs can illustrate this problem very well. Most of the time, pre-made balconies are quantified by the number of units that has to be built. Therefore, the tool was made to understand the schedule-extracted quantity as a number of units, and compute all the needed equipment from this number of units. However, it can happen in quite rare situations that the pre- made balconies are quantified by the length that has to be built, for example if it is a long balcony. The choice made here during the tool implementation was to foster the simplicity of the tool (and consider that pre-made balconies quantities are always units) over its adaptability, that would have required the user to manually enter the unit of every quantity. Therefore, if a user can only deal with lengths quantities, they would have to modify the calculations formulas for the related equipment. This search of balance and choices like this are subjective choices about the spirit of the tool, and only a long-term
24 | Conclusions and Future work
use can tell if the decisions made bring more efficiency or if they are more a constraint to the user.
A second balance that has to be found is the balance between giving the ability to the user to modify the stored default data, and maintaining the proper functioning of the tool. These modifications of data from the user without altering the functioning of the tool have to be easily doable in two ways: for light modifications, directly through the Excel interface, and for bigger modifications through access to the VBA code. The easiest type of modifications to allow and handle are the modifications of the code, for two main reasons. First, unlike the tool interface which has to be as concise as possible, the code can contain as much comments as needed, in order to guide a new user that would want to modify it, and the information can be structured in a way that is purely practical, and doesn’t have to answer to aesthetic constraints. Then, any user that would think about modifying the code is a user that knows what they are doing, and there are fewer chances that they modify something without wanting it. The biggest challenge concerns information easily accessible by the user, and easily modifiable. It needs to be that way because it is information which is common to all the projects, but which can be often subject to change. Therefore, these modifications are necessary if we want the tool to stay up to date. Due to this necessity, the risk of a spoiling modification by the user can’t be discarded. However, a proper utilisation of the tool consisting in copying the blank document before filling it easily ensures that any wrongful modification can be easily canceled and won’t have any consequence on the functioning of the tool.
5.4 Future work
Two main evolutions can be considered in order to improve the implemented tool. The first and easier one is the automation of a specific quantity need : the needed shoring towers for an alveolar floor. As of now, this quantity is needed as a user input as it results from a complicated calculation that requires a lot of input (the type of girders used, the span of the floor, the thickness of the floor, etc.).
The second evolution that can be considered doesn’t concern the equipment supply planning, but the equipment use planning. It is the implementation of a whole new tool: the automation of the wall panels turnover. Currently, once the quantities of wall panels are defined, the next step consists in manually deciding the order in which the different wall sections will be cast, and to divide them into blocks, each block corresponding to a day of work. This
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division, called wall panels turnover, depends on the wall panels that will be available and on the configuration of the walls. As this configuration varies a lot from one projects to another, the turnover is currently established manually, and it requires a lot of time in order to find the optimal configuration.
Therefore, it could be considered useful in the future to try to find a way to automatize this task. The difficulty seems greater than the automation of the supply planning, particularly because it requires interactions with blueprints, but the gain of time and efficiency can be massive.
26 | Conclusions and Future work
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