A CONTRIBUTION TO PRODUCTION PLANNING IMPROVEMENT IN THE CONSTRUCTION INDUSTRY THROUGH THE ANTICIPATION CONCEPT

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1 A CONTRIBUTION TO PRODUCTION PLANNING IMPROVEMENT IN THE CONSTRUCTION INDUSTRY THROUGH THE ANTICIPATION CONCEPT Ricardo Luiz Machado, Dr.Sc. Catholic University of Goiás, Department of Industrial Engineering, Avenida Universitária, 1440, CP. 86, CEP: , Goiânia GO, Brazil Luiz Fernando Mählmann Heineck. Ph.D. Federal University of Santa Catarina, PPGEP, CP: 476, CTC/EPS, CEP: , Campus Universitário, Florianópolis SC, Brazil Abstract: This article presents a synthesis of a doctorate thesis that proposes a model to improve the production planning process in the construction industry through the systematization of management anticipatory measures. Such systematization is performed through three sequential steps: identification of anticipations that should be present in the production flow; interpretation of what sort of managerial action might be related to the inclusion those anticipations; and due consideration and placing of such management actions in the production planning process. Multiple case studies were conducted on real sites, developing a number of examples of possible anticipatory measures. Most of the time, the lack of proper consideration of such measures was related to problems in the flow of work, thus giving support to the need of improving the building site planning process through this new concept. A number of anticipatory measures are illustrated throughout the text. Keywords: Production planning; Anticipation; Construction industry. 1 Introduction The area of construction planning and control is being under investigation for now some 50 years, since the introduction of PERT/CPM in the middle 50. The fact that evidences of their practical success are rare indicates that much more research should still be devoted to this area, due to its potential contribution to the building industry.

2 It might be said that there is already a distinct production planning and control (PPC) discipline as applied to the construction industry, inspired by the seminal work by Alexander Laufer (LAUFER & TUCKER, 1987, 1988, LAUFER, 1990, LAUFER, HOWELL & ROSENFELD, 1992). He introduced the idea of a planning process, that should be improved and mastered by construction practioners, rather than relying just on planning techniques. It is also of cornerstone standing the work by Glenn Ballard whose major contribution is the idea that action will occur as planned only if operatives find them feasible, are capable of coping with it and willing to perform (BALLARD 1994, BALLARD & HOWELL, 1998 and BALLARD, 2000). In Brazil, relevant investigations were carried out by Mendes Jr. (1999) who addressed the computational tools appropriate for each level of the planning process hierarchy and Bernardes (2001) who put forward a systematic planning model at the strategic, tactical and operational levels. He also investigated reasons for successful planning implementation at this latter lower end of managerial action. The research gap seems to rest on the nature, amount, and quality of information that feeds the planning process. For example, operational level information is neglected to the field of informality, taking for granted that operatives will have them, timely take them into consideration and display the necessary intellectual skills to deal with them (MACHADO, 2000). To consolidate the planning process in construction more should be understood about systematic information management according to KOSKELA, (1992), LAUFER & TUCKER (1987), BALLARD & HOWELL (1998), MENDES Jr. (1999), MACHADO (2000) and BALLARD (2000). A specific kind of information is addressed in this research work, namely the connection to elements that might represent hindrances to the normal flow of work on construction sites. Such information is systematized through a number of case studies and then introduced in the hierarchical model of production planning that now represent the state of the art in this field of knowledge. 2 The Production Planning and Control (PPC) for the construction sector Originally, PPC for the construction sector was characterized as a good example of straightforward application of Gantt Charts or CPM/PERT nets, what nowadays is taken just as a long term planning initial step (MENDES JR., 1999).

3 In the past actual day to day operations, shop floor organization and the removal of restraints to the normal flow of work caused by external sources are left to informal plans, if any. No duly attention was formally paid to details of execution, technological implications of different building techniques, production rhythm, production capacity of machines and labor, sequencing of work, effort synchronization of different work places and integration between different planning time horizons. It should not come as a surprise that work on site was prone to delays, interruptions, rework, lack of sequence and low productivity. The quest is for planning (and a process of planning) for everything that might happen on site, at any level of the work breakdown structure and at any time horizon. If planning is by definition the previous evaluation of means and their proper scheduling to achieve an end, it might be asserted that production will benefit from before the fact planning exercises whatever, wherever, whoever and whenever it deals with. Moreover, managerial actions might be induced by these planning efforts both to take place prior to work execution of while it is under way, increasing the chances that things will happen on site as desired. The problem is that both planning and management actions will exponentially grow as time consuming undertakings, making it even less likely that PPC will be used. The solution involves the redefinition of the planning model, creating opportunities for long, medium and short term scrutiny of means and aims. Additionally planning will be enacted only according to the certainty with which information is available. Information will be provided with increasing certainty as scheduled due dates are approached either by external/ internal sources or, more in line with the approach followed in this paper, by deliberate management efforts to amass, produce and systematize production data. At the operational level it is still an open question who should do the planning. In order to lessen managerial burden a number of authors propose that staff and field manager s planning should concentrate at the upper end, that is, at strategic and tactical levels. This also can be said in connection to time horizons long term and medium term (look ahead) are the realm of planning officers while short term is left for shop floor operatives and supervisors. Further to that, managerial effort can also be alleviated by drawing most of management actions needed at tactical level in the form of CPM-like nets (operational nets). Such operational nets will make it automatic

4 recovering of should be done on site according to best practices suggested by previous experience. A hierarchical Production Planning and Control model that might accommodate what was previously discussed might look like the one depicted in figure 2.1. Figure 2.1: A hierarchical model of building PPC 3 A systematic view on anticipations 3.1 The meaning of anticipations in a PPC context Machado (2003) puts forward 4 steps for a systematic view on anticipations: 1) Identification of elements that cause disturbances to the work flow and the hypothetical appointment of management actions that might be associated with their non-occurrence; 2) Identification of elements that are connected to work flow improvement. By the same token, management action should be conceived to guarantee their presence on the building site; 3) Inclusion of prospective management actions, previously devised in steps 1 and 2, into production plans;

5 4) Evaluation of outcomes assuring that such anticipations are connected to a better work flow and that their enacting is feasible in economical and managerial burden terms. In order to identify anticipations, managers should contemplate what can go wrong or can be improved in the daily operations on site. Management takes the lead and acts before execution takes place. Management action occurs before usual planned project operations take place. In extreme, previous management action that was expected to occur while actual operations are under way on site becomes unnecessary. Anticipation is a substitute for task management while work is in progress. Anticipation concepts do not aim to change the paradigm of PPC as it is carried out in construction projects. It aims it increase awareness about a neglected aspect of conventional planning. It is not just programming, thought, evaluation of alternatives, production of information and risk analysis that stem from planning, but also a prescription for management action before physical task connected action takes place. In general, this sort of awareness is better fostered by detailed work flow analysis, or careful monitoring of its disruption. Detailed work analysis will help conventional planning that normally takes into consideration only aggregated information and the whole set of activities that are necessary to bring project to completion. Anticipation concept is designed for PPC process improvement; it is not an end in itself, but a complementary undertaking while planning. Laufer (1990) was one the first research workers to advocate the inclusion of actions like anticipations in formally derived production plans. According to him, deciding how to conduct activities in the future is part of the planning process, but plan implementation is the most important step in the planning process. In order to avoid future mistakes while conducting activities, preventive decisions should be implemented in the present. In a sense, planning implementation means working more in present time in order to get work done right in the future. Bernardes (2001) maintains that many of the problems that cause interference in the rhythm of production are related to restrictions in the work environment. The inclusion of precautions during plans elaboration might reduce their detrimental effects. For him, medium term planning is suitable for this undertaking, as it allows sufficient time for

6 managers to scrutinize possible causes of disturbance and to react before real action takes place. Koskela (2000) relates anticipation to a decrease in work flow variability. Neglected anticipation actions would be the cause of process variability (or deviations from a standard or planned production stream). As he is worried about the fluid nature of work, he devised seven categories of pre-requisite flows that should feed every job assignment, as graphically depicted in figure 3.1 Figure 3.1: Basic inflow of inputs for task production planning Koskela (2000) stresses that most of the hindrances at the work place are caused by an uncertain flow of resources, at it is the case of project details that are late, or the lack of working conditions due to a severe climate. It is interesting to note that for both disparate examples something can be done to maintain work flow on site. In the first, case management action can be in the form of visits to designers in order to speed up the delivery of just the needed pieces of information (in the right sequence). In the second case it might be related to better whether forecasts or work place encapsulation Especial and regular anticipations According to Machado (2003) anticipations are identified in cycles, within a project or from project to project. Figure 3.2 presents a production planning and control inclusion cycle:

7 Figure 3.2: Production Planning and Control cycle for anticipation inclusion Anticipations can be categorized into special and regular ones, depending on how often they are taken into account by PPC cycles. A special anticipation is normally employed upon just once during the project lifetime. Work flow evaluation and improvement occurs in the form of learning based on global performance of previous projects. It is project specific, and would be taken into consideration only for projects of similar characteristics. It is the case, for example, of providing a special drainage system for sites under threat of floods, high standing water levels or a heavy rainy season. Regular anticipations are common to many production processes and should be documented in the form of standard management action compendiums. Rosso (1990) identifies thirteen regular categories of anticipations: 1) equipment procurement, 2) material procurement, 3) tooling, 4) material selection, 5) transportation of resources to the work place, 6) set out (design translation into actual site references, marks and gauges), 7) installation of ancillary equipments (like scaffolds), 8) protection of equipment, 9) technology transfer, training and process development; 10) tests; 11) cleaning, 12) inspection and 13) work place dismantling. Those categories can be taken as a first suggestion for both special and regular anticipations. This research work will expand those categories. The need for special anticipations will be observed on three case studies. In parallel regular anticipations will be collected according to literature suggestions, analysis of individual building processes within the project case studies and technical recommendations for best practices in construction.

8 4 Research methodology Research steps and their sequence can be assessed through the examination of figure 4.1: Figure 4.1: Research scheme 5 Research results Field work various steps provided a gradual refinement in the process of unveiling new anticipation examples and categories. Initially, Koskela (1990) model depicted in figure 3.1 was taken as a checklist to evaluate how his seven categories of flow were feeding actual conversion work. Management action directed to the proper provision of materials and equipment was the most noticeable anticipation being performed. Later on, examples started to be found in connection with more sophisticated aspects, like giving access to the working place, carrying out of tests and inspections and making sure that design geometrical measures were properly set out on site. At the end, more and more examples were not able to produce more anticipation categories (convergence took place), allowing theoretical generalization of results. Some of the anticipation categories were advanced by literature review, like tooling, provision of project details and resource transportation to the working place. Other categories were supported by practical evidence, like preventive maintenance of equipments, mould provision (as in the case of granite kitchen benches ordering), prototyping (as in the case of ceramic tiling) and material selection (as in the case of working with wooden components, with different color patterns). Anticipations were most of the time noticed after the fact, that is, neglected action in their respect was taken as the cause of production flow disruption. It is still an open

9 question if proper anticipation measures, rightly and timely put into place, might be associated statistically with better performance. The major contribution of this research work is then connected to the categorical systematization of anticipations, after they were exhaustively identified. What follows is a description of these categories: 1) Anticipation in connection to precedence work; 2) Anticipation in connection to projects; 3) Anticipation in connection to materials management; 4) Anticipation action in connection to the provision of equipments and tooling; 5) Anticipation action in connection to site safety; 6) Anticipation action in connection with inspection; 7) Anticipation action in connection to accessibility; 8) Anticipation action in connection to transparency; 9) Anticipation in connection to horizontal and vertical setting out; 10) Anticipation in connection to pre-production on site; 11) Anticipations in connection to the availability of storage space for especial building components; 12) Anticipations in connection to the creation of a proper working environment; 13) Anticipations in connection to water and energy supplies; 14) Anticipations in connection to disrupting technical precedence of activities; 15) Anticipations in connection to temporary protection of finished parts of the work; 16) Anticipation in connection to First Run Studies; 17) Anticipation in connection to performance tests; 18) Anticipation in connection to the taking down of geometrical measures; 19) Anticipation in connection to the creation of moulds; 20) Anticipations in connection to weather; 21) Anticipation in connection to an unbalanced match between workload and production capacity; 22) Anticipation in connection to cleaning, trimming and making good; 23) Anticipation in connection to waste management. 6 Including anticipations in Production Planning ng and Control Figure 6.1 is complementary view on figure 2.1. The latter illustrates PPC techniques that might be used at long, medium and short term time horizons. The former associates time horizons with strategic, tactical and operational levels of planning.

10 Figure 6.1: Inclusion of anticipations in hierarchical building PPC model A combined view of both figures makes it clear that as strategy relates to the project as a whole, it should be though off with a long term horizon. As tactics relates to parts of the project, its corresponding planning activities are better dealt with in time horizons corresponding to smaller periods. By extension, short term planning is the realm of operational decisions. Most of the examples illustrating anticipation categories throughout this paper pointed out to their medium term and tactical nature. In fact, major lead times for implementing management actions associated with anticipations will recommend their inclusion into medium term planning. By the same token, anticipations are more appealing when they can influence bigger parts of the job, instead of individual activities, thus corresponding to tactical planning. Special anticipations, unique for each particular project, fall into this category. Regular anticipations, repeatedly employed for similar activities in different projects, are accommodated by operational plans. Thus the PPC model depicted in figure 6.1 shows anticipations acting at both levels of planning. It should be stressed that they will not affect long term or strategic planning due to a matter of definition. Anticipations are those management actions that are not formally incorporated into PPC either because they were unnoticed by management or because their enacting was taken for granted.

11 Daily control will pinpoint more unnoticed possible anticipations and will suggest their formal inclusion into PPC. This feedback from daily control to anticipation thinking will increase learning abilities on site. Moreover, they will contribute to the creation of enlarged data banks of special and regular anticipations that might be taken into account by managers in the future. 7 Final remarks Both the 23 categories of anticipations and the PPC model illustrated by figure 6.1 were taken to field personnel in case study 3. Graphical slides, photographs and technical description of building operations were submitted to them asking how they will react if they have had the chance of incorporating anticipations into production planning. Interviews indicated that managers agreed with anticipation categories, find them relevant and useful. Some of field managers added that they already take into consideration, due to practical experience, but are unable to systematically address them before action starts on site. Enforcing the use of anticipation concepts at medium term and tactical planning seems to be a sensible way of coping with this extra managerial burden. At this stage special anticipations might cater for parts of the job, that is, they did not need to be repeated for isolated activities. Moreover, medium term action relieves time pressure to act here and now. Following the same lines, regular anticipations might be part of operatives training and skills, freeing managers to dedicate their time to special anticipations at higher levels of production planning. References BALLARD, G.; HOWELL, G. (1998) - Shielding Production: Essential Step in Production Control. Journal of Construction Engineering and Management, Vol.124, Nº1, pp BALLARD, G. (1994) - The Last Planner. Northern California Construction Institute Publication. Monterey, CA, pp , April. BERNARDES, M.M.S. (2001) - Desenvolvimento de um Modelo de Planejamento e Controle da Produção para Micro e Pequenas Empresas de Construção. Porto Alegre -

12 RS, Tese de doutorado apresentada ao PPGEC da Universidade Federal do Rio Grande do Sul, 291 p. KOSKELA, L.. Management of production in construction: a theoretical view. Proceedings IGLC-7, University of California, Berkeley, CA, USA, pp , july, KOSKELA, L. (2000) - An exploration towards a production theory and its application to construction. Espoo, Finland. Dissertation to the degree of Doctor in Technology presented to the Helsinki University of Technology, 298 p. KOSKELA, L. (1992) - Application of the new production philosophy to construction, Technical report No. 72, CIFE, Stanford Universtity, Stanford, California. LAUFER, A.; HOWELL, G.A.; ROSENFELD, Y. (1992) - Three models of short-term construction planning. Construction Management and Economics, Vol. 10, p , LAUFER, A.; TUCKER, R. (1988) - Competence and timing dilemma in construction planning. Construction Management and Economics, Vol. 6, p LAUFER, A.; TUCKER, R.L. (1987) - Is construction planning really doing its job? A critical examination of focus, role and process. Construction Management and Economics, Vol. 5, p LAUFER, Alexander. (1990) - Essentials of Project Planning: Owner s Perspective. Journal of Management in Engineering, ASCE, Vol. 6, No. 2, p MACHADO, R.L. (2000) - Um Modelo de PCP de Curto Prazo para a Construção Civil. III SIMPOI, Fundação Getulio Vargas, São Paulo SP, Brasil. MACHADO, Ricardo Luiz. (2003) - A Sistematização de Antecipações Gerenciais no Planejamento da Produção de Sistemas da Construção Civil. Florianópolis SC, Tese (Doutorado em Engenharia de Produção) - Programa de Pós Graduação em Engenharia de Produção, Universidade Federal de Santa Catarina.

13 MENDES JR, Ricardo. (1999) - Programação da produção na construção de edifícios de múltiplos pavimentos. Florianópolis SC, Tese (Doutorado em Engenharia de Produção) - PPGEP, Universidade Federal de Santa Catarina, 235 p.. ROSSO, T. (1990) - Racionalização da construção. São Paulo, SP: FAU-USP, SANTOS, A. (1999) - Application of Flow Principles in the Production Management of Construction Sites. Salford UK, Tese de doutorado apresentada ao School of Construction and Property Management of the University of Salford, 463 p.. SLACK, N.; CHAMBERS, S.; JOHNSTON, R. (2002) - Administração da Produção. São Paulo, SP: Editora Atlas, 2 ª. edição, 747 p., 2002.