Zakaria Dakhli

Application of lean to the bidding phase in building construction: a French contractor’s experience

Purpose While many procurement systems govern the construction sector, Design/Bid/Build is still prominent among the French building actors. The research applies Lean thinking (via a kaizen event) to the bidding phase of a building construction company to improve its bidding outputs. Design/methodology/approach The method used in this study is “Action-Research”. A two-month preparation phase was needed to prepare for the kaizen event. The results were based on an assessment conducted after 6 months of the kaizen event. Performance was measured following selected indicators related to ‘Time’, “Economical Impact”, “Quality” and “Sustainability”. Findings The Lean implementation had positive side-effects on the company’s organization and strategy as well. Practical implications The findings of this action-research project can be used to help researchers and practitioners assess the potential application of Lean in the bidding phase. It also provides insights into the importance of the cultural and existing practices for a successful Lean implementation. Originality/value A few research projects investigated the application of Lean thinking in bidding as it is considered as a wasteful process. However, waste can also be organized. The research proves that bidding can benefit from Lean thinking.

Experimental and numerical prototyping of a complex cement column formwork for construction

ABSTRACT Complex shapes in civil engineering require complex and unique molds. Starting from the fact that 3D printing technology primarily targets this type of product, this paper investigates the potential adaptation of 3D printing in the mold and formwork industry. A small-scale printing test was realized to build a complex architectural design prototype using cement. The results are presented according to three phases: 1 – Selection phase: 3D printing technology was selected and the adequate printing material. Experimental and numerical studies were realized to assess the material. 2 – Adaptation phase: the 3D printer was scaled for use. 3 – Prototyping phase, that deals with printing the formwork and evaluating the cement poles. The research proved the feasibility of using 3D printing technology to produce complex-shaped prototyped formworks for cement poles in construction.

Durability of textile facing materials for construction: Implementation of an accelerated aging test by hydrolysis

This paper presents the design and development of a test protocol for accelerated aging by hydrolysis in basic and acidic media, as well as application of this protocol for testing two fabrics intended for use as facing materials for buildings. The durability indicators were selected in order to quantify and analyse the impact of accelerated aging on fabrics. The experimental results reveal that the two fabrics’ behaviour depends on the medium’s nature. The aging in an acidic medium was hardly noticeable. Conversely, aging in a basic medium resulted in a quick deterioration of the fabrics: after 35 days of aging, the tensile strength of both fabrics was close to zero. Furthermore, the two fabrics behave differently in the basic medium, which is mainly due to their separate structures: the first fabric resistance to nail tear increased during the first day of aging unlike the second fabric.

Characterization of Waste in Ethiopian Building Construction Projects

According to the February 2017 Mckinsey Global Institute report, construction industry is one of the largest sectors in the world economy with

Robotic mechanical design for brick-laying automation

10 trillion spending, 13% of GDP contribution and 7% employment opportunity annually. However, the sector laborproductivity for the past two decades couldn’t exceed 1% a year while the total world economy and the manufacturing sector has been grown by 2.8 and 3.6 % respectively. As a result of this, the industry loss a value of

Durability of textile facing materials for construction: Operating accelerated ageing protocol results in basic medium for lifetime estimation in conditions of use

1.6 trillion a year that would meet about half of the world’s annual infrastructure needs or boost global GDP by 2 %. According to this report, Ethiopia is the last in the list of countries with poor productivity. Considering the above fact, this study assess building construction projects in Ethiopia with respect to the common types of waste in order to identify the most important waste in Ethiopian building construction projects. Accordingly the study confirmed that close to 40% of the project time is wasted in performing non value adding activities due to over production, over processing, Transport, motion and waiting related wastes.

Experiencing Lean Six Sigma in the French residential construction: Setting effective performance indicators to address client satisfaction

Abstract This paper investigates the potential for automation of masonry work. A brick-laying robot was designed and the robot’s design criteria were such that it should be able to construct a wall using cinder blocks autonomously. The paper outlines considerations for the entire process of implementing the robot, from material input and stock management to construction process by the robot itself. The design included the functioning of the brick-laying robot’s head. Finally, comparisons were made in terms of cost and time efficiency between the robot and traditional methods for masonry assembly. The results revealed that the designed robot optimized time and cost deliverables with a noticeable waste reduction and an increase in productivity.

Efficient logistics enabled by smart solutions in tunneling

The building industry is now evolving in a rapid pace due to the massive need to build and rebuild the cities. While designing the building, the owner appreciates the esthetic aspects, whereas the contractor is more interested in a performance-based approach for its construction. The current study investigates the integration of industrial textiles in buildings. For that, life spawn estimation of textile materials is crucial due to the different existing French regulations that set a minimum durability criterion. The paper presents a methodology for lifetime estimation and an application to two fabrics intended for use as facing materials for buildings. A series of aging tests were carried out and extrapolations were made to reach the research goal. The results of tests that were carried out indicate the feasibility of the textiles’ lifetime estimation methodology used.

Development strategies for the French construction sector

Purpose Compared to the manufacturing industry, Lean Six Sigma (LSS) lacks a clear methodology for its application in the tertiary service. One reason is the difficulties to assess information flow compared to physical flow. Indeed, the use of information flow as a process entry in the LSS method is not well investigated, mainly due to the difficulties in collecting adequate and sufficient data. The purpose of this research study is to investigate the application of LSS in the tertiary service, in particular, real estate development. Design/methodology/approach The paper is based on an action research methodology where LSS methodology is applied to solve client-dissatisfaction issue. One of its main causes is found to be the late delivery time. The work describes how the method was applied. Findings LSS is an adequate approach for making well-thought-out improvement in real estate development. Practical implications The work provides an implementation of LSS in real estate development. It also gives new insights into the LSS application in the tertiary service. The work also suggests practical recommendations and solutions to address the main challenges faced by real estate development. Originality/value Construction is governed by many processes that are difficult to identify and, even more, to assess. LSS helps identifying those which create real value for the client.