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Management 2015, 5(5): 141-147 DOI: 10.5923/j.mm.20150505.01

Assessing Consequences of Change Request Impact in Construction Industry of YEMEN: An Explorative Likert-Scale Based Survey Design Murlidhar A. Lokhande1, Farouk Saif Yahya Ahmed2,* 1 Professor, at Department of Commerce, Dr, B. A. M. U, Aurangabad, Maharashtra, India Research scholar at Department of management science, Dr, B. A. M. U, Aurangabad, Maharashtra, India

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Abstract The linear construction projects of YEMEN are the basis of the study, focussing on the requirement of change

orders in the several stages of the projects. The work presented here is defining the potential survey questioner to obtain the reliable and optimal data from construction industry of YEMEN. The data obtained will be used further to assess the change impact consequences and possible directions of prevention. The overall survey planned in 3 dimensions and they are finding the severity and scope of the change request impact, consequence certainty of the change request impact and the preventive strategies followed to avoid the consequences of the change request impacts. The overall 21 benchmarking functional and non-function construction standards are defined to prepare the questioner and the same is used to obtain the construction industry opinion, beliefs and practices through the said three dimensions of the survey.

Keywords Construction project management, Change request, Construction planning, General construction, Engineered construction, Likert-Scale

1. Introduction The construction projects related change orders and the subsequent conflicts are the main causes of major problems in the industry such as, delays in project completion, increase in cost, and defects in quality. A change may be because of an addition, deletion, or revision of the project scope. The reasons behind change orders widely differed as stated by Naoum in the paper [1]. The causes behind project changes are mostly, communication inefficiency of not being in time and being ineffective, improper integration, ambiguity, environment changes, and aggregation of project complexity. The substantial effects of change orders on the projects time period and on the direct and indirect involved cost factors can be assessed from a project management standpoint. The works of constructing roads, electricity cabling, water and sewage works including other works are involved in projects of linear construction and these projects are regarded among all the infrastructure projects the most vital projects. A roads project for example has several specialized categories such as, tunnels, bridges, retaining walls, runways and jetties according to the YEMEN System for Contractors Classification. * Corresponding author: [email protected] (Farouk Saif Yahya Ahmed) Published online at http://journal.sapub.org/mm Copyright © 2015 Scientific & Academic Publishing. All Rights Reserved

The linear construction projects are executed to great stretches either above or below the ground. The linear projects are implemented taking into account the benefits to a wide population group. The project implementation is very expensive comprising of unknown challenges, mostly in terms of the factors geologically existing with risks involved being both familiar and unfamiliar. The implementation of linear project to great extents above ground or underground is the main factor that differentiates linear projects from different other types of construction projects. In this paper we study the major linear construction projects implemented by the YEMEN governments Ministry of Transport and Ministry of Water and Electricity. These projects are considered in the study of the “change orders” to recognize the causes, impacts, as well as the severity, due to the change and assess the best practices in management and control of change orders.

2. Literature Review In the process of any project, changes occur usually on a daily basis and change the form of work implemented, construction approach, quantity of the work and result in changes of amount of resource associated to labour and material. In the construction industry change orders have been traditionally part of the process and are not a new concept introduced.

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The study by Thomas and Napolitan [2], Ibbs [3], stated that clients task of change management becomes challenging due to the wide differences in the causes of change orders. In the paper [4], Leonard et al. give the causes of change orders as of 3 types such as, errors and omission in the design, changes in the design, and unfamiliar conditions not foreseen. The study of Johnson [5] gives 4 different conditions and stated that the cause for change orders could be any one of them. The factors given are, the geographical conditions documented before and the actual different conditions found below the surface later, the differences that appear contrary to assumed conditions in the work of re-modelling prevailing building, client change requests, and finally reviews of regulatory mechanism. The causes of change orders in construction projects have been studied by different researchers who have given several strong reasons behind the change orders. A study [6] by Hsieh et al. takes into account, ninety different successfully implemented public construction projects in Taipei metropolis, Taiwan. The change orders recorded of projects finished prior to year 2000 are reviewed with a comprehensive orderly classification of the causes affecting the change orders. The causes are classified first into 2 categories, i.e. technical and administrative causes and further grouped into 9 sub categories. A ranking is given to the change orders based on their impact levels of 7 factors and 34 causes. A study based on Taiwan highway construction projects by Wu et al. in the paper [7] focuses on the Second National Highway construction project. The review collected all the project management approved and issued change orders and analysed change orders of 1038 in total. The analysis finds 34 different causes which are classified into 4 groups based on who has introduced the change in terms of, owner, design consultant, on-site construction unit, or external parties which also comprises of all other parties not belonging to the first 3 groups. In the paper [8] a review of 865 construction projects by Hanna et al. finds that in 87 per cent of the completed projects, 6413 different sizes change orders implemented. The study finds the causes of change due to, insufficient field investigations, uncertain specifications, plan errors, or changes or mistakes of the design by the engineers consulted and concluded that of the total 6,413 change orders one-third of them were avoidable. The paper [9] conducts a survey of huge size building construction projects in YEMEN’s eastern province by Al-Dubaisi. The study attempts to determine the major reasons behind the change orders and their level of impact and stated the primary reason of change orders are the owner initiated changes in the plans and the secondary reason being changes in material or procedure or both. The study by Wu et al. in the paper [10] observed that the construction delays and cost escalations in maximum number of public construction projects is mostly due to change orders which impact morale, quality, and result in disputes legally. Similarly a study by Finke in the paper [11]

stated the change orders impacts on the working condition may be, deviation of resources, weakening of skilled labour, congestion in the work places, stacking of trades, discrepancies in supervision, disruptions in continuity of work, and hence overall delay in all the activities. A categorization of the impacts of change, divides the change effects into two types, direct effects and indirect effects. A direct effect of a project change for instance is rework in a project which is a major cost factor impacting a project, sometimes nearly 10-15% of the total project cost, as stated by EPSRC (Engineering and Physical Sciences Research Council) [12]. An indirect effect also impacts the cost and schedule of the project according to the changes in the project. A second type of classification of the effects of change orders, categorizes [13] the effects into two types, direct effects and consequential effects, which is by the CII (Construction Industry Institute). The effect as a result of a change causing impact in the same project scenario where the change has been implemented is a direct effect, whereas the effect due to a change resulting in an impact in another project scenario and not in the same scenario in which the change was implemented is known as a consequential effect. These two types of effects due to a change have impacts of cost or time or both. In the paper [14] by Assaf and Al-Hejji, a survey of YEMEN stated different kinds of project of construction, attempts to find the causes of delay and establishes that according to the projects stakeholders the change orders are the most general cause of delay. A survey of similar nature in Jordon by Al-Moumani [15] and in Hong Kong by Chan et al. [16] finds the change orders to be the major reason of delay in construction projects. The study of change effects on labour productivity in the paper [17] by Leonard reviews 90 claim cases of different contracts in every aspect. The author categories the cases into, civil/architectural and mechanical/electrical groups and depicted the percentage loss of productivity as a function of the percentage of the change related total work hours. The study finds productivity loss of 10-20 per cent for every 4-5 fold increase in percentage of work hours expended related to change. The work of Hanna and Gunduz in the paper [18] for controlling of change orders, suggests minimizing change orders processing time or reduction in the time in-between a change order’s initiation and subsequent approval, which according to them will result in lesser loss of productivity. An approach for decreasing changes of design in the paper [19] developed by Westmoreland is based on identifying in the review process most of the design changes, and suggests incorporating two criteria which are, first a recheck of the plan followed by a review of the specifications and second a review of the constructability. In minimizing rework, specifically related to design changes by Love in the paper [20], shows the strategies that can be implemented such as, freezing the scope of the design, value management (VM), constructability analysis, and teambuilding. The work by Love et al. [21] for decreasing

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the rework in construction projects mostly as a result of the common change orders, offers several suggestions such as, client and end-user requirements determination, comprehension and mitigation of change with suitable strategies, the change and errors potential determination in terms of risk assessment based on contract documents auditing, and enhancing skills and knowledge with the help of programs providing training.

3. Research Objectives and Methodology The study aim is exploring the change orders of construction projects of linear model implemented in YEMEN and includes all projects of all regions in the state. Apart from this main objective other definitive objectives are, (1) identifying the most significant causes, (2) determining the most authoritative party of all, (3) identifying the most significant impacts of all, and (4) determining the best practices for change order management and control. Based on the literature review results and the above research objectives, a survey is designed with questionnaire for construction projects owners, consultants and contractors. The MoT (Ministry of Transport and MoWE (Ministry of Water and Electricity) are part of the owners surveyed in all the branches in the entire province of YEMEN State. The consultants certified in design and projects supervision by the owner group are surveyed. The contractors surveyed are those who have been rated by the YEMEN Contractors Classification Agency as grade I or II top contractors. In every sub-population sample, the size is calculated using the explorative data analysis [22] and the data is analysed based on different methods of statistical analysis with predictive analytics SPSS™ software and tools such as Excel™. Empirical Study and statistical assessment of the contributions: The survey implemented by us is for studying the practical problems faced in the construction industry of YEMEN, which will be assessed I our future article with the scope of the contributed strategies and the optimality of the contributed strategies over current strategies.

4. Questionnaire Design The survey questions are designed based on the previous literature of construction projects change orders and are separated into five parts. In section 1 common question’s for feedback are included such as the participant’s profession, experience, and individual projects specialization. In section 2 questions for feedback on change orders related issues such as, agreement levels in acknowledging a problems existence, ownership levels of the causes initiating the change orders, reasons behind a change order related surge in expenses of a project, their role in work areas which have taken a maximum hit in productivity, along with questions about the duration in which change manifestation is more, and about

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the chief causes of change order procedural related delays. The questioner is of 21 queries, such that each query reflects one among the benchmarking cause of change requests. The initial questioner is keen to verify the change request impact severity and impact towards the factors such as "Financial", "Project Time Schedule", "Quality Factors" and "Resource acquisition". The second survey questioner is aimed to assess the impact type observed against 21 benchmarking change request categories. The impacts of change requests is categorized into 11 cases and these are "Decrease in productivity", " Delay in completion schedule", "Dispute between owner and contractor", “Decrease in quality of work", “Increase in project cost", "Additional revenue for contractor", "Delay of material and tools", "Work on hold in other areas", "Increase in contractor’s overhead", "Demolition and re-work" and "Delays in payment to contractor". The third questioner is to assess the recommendations of the target clients towards strategies to prevent the impact of the change requests. These prevention strategies are also classified into 11 cases and these are "Early setting of change request handling procedures", "Timely approval of change request", "Negotiation by knowledgeable people", "Appropriate approval in writing", "Giving consideration to indirect effects in change request pricing", "Clarity of scope of change", "Checking and review of design changes for feasibility", "Review of gray areas in contract documents”, “Freeze of design”, “Team effort between parties" and "Work break down structure". It is to be noted that a few participants showed apprehension on the way the changes are managed giving support to the opinion about, chaotic and unsystematic change management practices. The frequency and severity of causes and impacts due to change order and the frequency of practices implemented are measured with explorative data analysis strategies.

5. Data Collection The survey questionnaire is given to participants who are the owners, contractors, and consultants. The communication process with each organization involved sending the questionnaires with a cover letter to the general manager and receiving the replies by fax and in a few cases however by hand the questionnaires were given and replies received. The communication was followed up daily over the telephone, for speeding up the responses, for providing clarification to the given questions, and to answer the respondent’s queries. The responses received following the sending of the questionnaires, are collected in a phase of two months which totalled to 65 responses. Many questionnaires did not elicit responses as the consultants who stated the reason of not designing or supervising any project yet though pre-qualified by the concerned ministries for implementing the projects. Out of the total responses received, 6 responses as a result of partial or false data are disqualified. So the qualified

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responses equalled to 59 from the different groups of owner, contractor, and consultant sub populations. The collected data is analysed as reviewed by using various methods of descriptive and inferential statistics of ANOVA [22].

6. Formation Significance of the Survey Questioner 6.1. Survey Questioner The survey reviews and appraises companies offering construction solutions in YEMEN. The design of the survey focuses on finding information of the company’s strategy and experience towards change impact due to various factors. The survey questionnaires are designed to acquire better insights in the comprehension of change impact and for establishing best practices in the implementation of change management. The questions or queries are modelled on various information concepts that are in the sequential order as follows. A. Change of plans or scope by owner In construction projects the owner specific change orders are a major reason for variations [30] attributed to lack of proper involvement in the planning and execution of the terms of contract, design and resources [26] affecting every phase of project implementation. B. Owner’s financial problems The financial issues of the owner are of many different types including those of economic, social, political factors. The financial related delay especially for big projects are raising capital or acquiring the government allocated budget. The other reasons are sudden price changes, invalid claims, inaccurate work valuation, that affects the owner cash flow. The diminished financial capabilities cause changes of project plans for reducing the project cost limiting the scope of implementing the project. The owner specific financial issues are the most important causes of delay in construction projects. The owner's planning and review of project cash flow, impacts the progress and success of the project and future prospects of securing new projects [32, 36]. C. Change of schedule by the owner A change of schedule by the owner implies for the contractor cost/schedule implications in terms of resources for the changed work process [34, 38]. To reduce the impact of a change affecting the entire program schedule, each and every program detail must be included in the schedule, with the current schedule status, reflecting the delays and possible impacts with reasons, the recovery initiatives undertaken for recovering the schedule and a probable date of completion. D. Limitations to define the projects objective A case of ineffective communication of the project objectives translates to unclear objectives including ambiguities and variations of critical disposition. This communication without relevant clarity and detail if involves various teams and associations working for the projects

objectives will have numerous change impacts in the projects implementation [36]. An effective and efficient communication approach enables the project stakeholders to work on problems and solutions with an overall view of the project implementation and realize common objectives and achieve success in accomplishing the overall project objective. E. Changes in material or procedures The materials change orders have impacts of fundamental procedural variations of strategy and implementation approach in the construction stage [28]. The adjustment of material change may be due several reasons such as, developer facing financial problems necessitating using of lesser quality material in place of costlier and quality material specified initially or site conditions requiring a more efficient material, or other reasons. This type of changes normally has procedural impacts of, manpower, equipment, time and capital expenditure. These procedural difficulties require the construction projects to have an effective material management process with proper material specifications, materials procurement, storage and installation with an effective monitoring mechanism. F. Conflict between contract documents A project with multiple stakeholders and multiple contract documents usually may cause confusion of the requirements planned giving scope to conflicts in the project results [29]. The contract documents when implemented by the various parties without proper coordination would have various types of impacts on the project implementation. A delay due to misunderstanding in one of the contracts would cause disruptions in other contracts schedule. The documentation of a contract must effectively convey the purpose and the relations with other contracts in the project for the successful project implementation without any chance for future avoidable obligations. G. Change in design by consultant Design changes related to the structure by an architect consultant or the technical designs changes such as mechanical/electrical changes by an engineer consultant can alter the project significantly with severe impacts. The changes of enhancement in the design, is a regular practice of project design consultants in the construction industry [26] and the frequency with which the changes occur is greater in projects implemented prior to the finalization of the design [34]. H. Scope of work for the contractor is not well The scope of the project involving detailed design, implementation and completion, must be described adequately to everybody involved. The projects scope if not clear before the execution will cause changes in the project plan, and design resulting in rework impacting the cost and schedule of the project. An extensive evaluation and clarification given about the project scope of work to all the project stakeholders involving owner, designers, consultants, vendors, and contractors, results in minimum change order

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impact in the project execution and results in successful implementation of the project [34, 26]. I. Errors and omissions in design A project when designed with insufficient detail, or with improper coverage of all the project aspects or with mistakes would cause strong change impacts in the construction affecting the work output [26] and the project schedule [27]. J. Lack of coordination between contractor and consultant A common practice in projects of construction is that work such as the project surveying, design, etc. is distributed and assigned to different consultants. The lack of proper coordination between the contractor and the consultant leads to the contractor being confused in the selection of material, equipment and manpower during project implementation. The complications that arise may seriously impact the project if not detected in the initial stages and handled with proper effort and knowledge by all the groups involved.

N. Contractor’s desire to improve his financial situation The profit motives of the contractor would cause request for adjustments in plans or budget, to make way for variations, based on ambiguities and defects in the plans and specifications. The major reason for variations in construction projects is the contractors who by influencing or suppressing information and by practices such as using different procurement methods, materials etc. increases his profits at the cost of the project quality. The general reasons for contractor implementing extra works are the variations proposed [38]. O. Contractor’s financial difficulties The financial problems of contractor may have important change order variations in a project, impacting the schedule and quality of the construction. The contractor’s financial capacity affected by delay in his obtaining payment is secondary, as the workers receiving payment in time is of primary importance [39].

K. Value engineering

P. Required labour skills are not available

Value methodology or VE process is finding alternative materials and techniques to improve the integrity and cost worthiness of the project. The implementation of value engineering during the construction phase (VECP) in terms of architectural and technology improvements for enhancing the overall functionality and/or cost effectiveness of the project, involves great risk of initiating multiple changes in the construction [33]. In terms of cost-worth analysis value engineering is practical if implemented in the design phase of the project [37].

Q. Required equipment and tools are not available

L. Technology changes The technologies associated with the methods, materials, equipment used in construction may change as newer beneficial technology becomes available. For instance, a newer construction mechanism may be incorporated or the latest systems may be installed in a building for the maintenance and long term cost benefits. The flexibility in including newer beneficial variations in the project planning stage [31] should be done with attention towards the associated unknown constraints involved. M. Differing site conditions The physical conditions if different from that represented in the documentation of the contract prepared inaccurately by consultants can be a major reason for delays [27]. The implementation of big construction projects such as highways, dams and canals are impacted by factors such as different soil conditions, existence of rock formations, or other reasons and are complicated by the damages, delays or claims by the contractor citing inaccurate contract representations. Some of the ways for managing the change impacts of increase in the project cost and schedule are, a proper site evaluation before the actual construction and after the changed conditions for an effective claims settlement, and right fiscal planning involving contingency funding for unexpected circumstances.

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Knowledge, skills and expertise in manpower is most needed [26] in projects having technologically complex requirements. A highly professional certified skilled manpower is required at the scheduled time and for the necessary duration, to implement the complex designs and construction methods, to perform essential tests, adjustments and troubleshoot problems. Any shortage of skilled workforce may be a reason for variations, demolition or rework resulting in delay and increased project cost. The availability of adequate number of tools/equipment, efficient procurement process, adequate knowledge in the selection of the materials, equipment or tools by the consultant are the determining factors for an in-depth development of design [38]. The delays otherwise may have several important variations of design or entire change of plan or substitution of certain materials, tools, equipment affecting project schedules [35]. The adjustments impacts the cost and such unforeseen conditions require proper contingency plans to make adequate resources available. R. Workmanship or material not meeting the specifications Workmanship defects in projects of construction have adverse effects leading to demolition and rework [34, 38] to accommodate changes, causing delays in project completion. The inspection at the conclusion of the project on determination of any specific poor workmanship it relates the constructions inferior quality [26]. The defective workmanship may be due to using incorrect or defective materials, unfitting installations, not implementing all project objectives, and inadequate supervision. S. Safety considerations All the people working in a project require safe and secure working conditions and if the safety regulations are not adhered to may result in, major accidents and design changes

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impacting the project schedule and completion. The safety and security procedures to be implemented for a successful project implementation are, regular safety checks, maintaining cleanliness, accident prevention, ability to handle emergencies, provision for training everybody in safety and maintaining adequate staff for the above processes. A major criterion for a construction project to be completed effectively is safety [32]. T. Weather conditions The changing weather conditions such as rain, snow, wind, and adverse temperature conditions have serious impacts on productivity resulting in delays in construction and variations in the schedule. Open construction projects have serious impacts due to the changing weather [34, 38] and the contractor has to make use of advanced predictive models for forecasting the weather and in projecting the delay of the project. U. New government regulations A project design should comply with the definite codes and regulations of the regional government bodies [26] and the implementation of changed laws during the construction stage of the project has seriously impact on the project, resulting in important changes in construction design. The project design if not complying with the government regulations may delay the project [32], complicate the projects safety, affects the projects progress and delay its completion. 6.2. Finding the severity and Scope of the Change Impact The first level of the survey aimed to find the impact severity and impact scope towards the consequences. The severity is assessed through the three point Likert scale [25] and the opted Likert points are "sever", "moderate", "no influence/not allowed". Similarly the change request scope also been assessed through four point Likert scale with the points "Financial", "Project Time Schedule", "Quality Factors" and "Resource acquisition"

YEMEN towards preventive strategies to avoid change impact influences and consequences. A like as of the dimension and two of the survey here in this dimension also the survey was done through 11 point Likert scale with points "Early setting of change request handling procedures Timely approval of change request", "Negotiation by knowledgeable people Appropriate approval in writing", "Giving consideration to indirect effects in change request pricing Clarity of scope of change", "Checking and review of design changes for feasibility Review of gray areas in contract documents", "Freeze of design Team effort between parties" and "Work break down structure".

7. Conclusions In this paper, the findings of the questionnaire survey is presented and discussed. The 21 causes, their 3 levels of severity scope, 4 levels of consequence of change request impact, 11 possible consequences and 11 preventive strategies were analyzed and covered in the proposed questioner. The survey questioner is prepared, which is based on LIKERT-SCALE. The survey questioner is aimed to find the beliefs and practices of construction industry of Yemen towards the change request impacts in three different dimensions and they are finding the severity and scope of change impact, consequence certainty of change impacts and preventive strategies to surpass the consequences of the change impacts. In future the data obtained through this survey will be used to assess the degree of change requests impact. In regard to this we will adapt the statistical strategies for explorative Data Analysis [R1].

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6.3. Finding the Influence Certainty of Change Request The second dimension of the survey is aimed to identify the possible consequences and their certainty. Hence the survey is initiated to explore the industry opinions and experiences in regard to this. The survey is conducted through 11 points Likert scale and the points involved in the scale are "Decrease in productivity Delay in completion schedule", "Dispute between owner and contractor Decrease in quality of work", "Increase in project cost Additional revenue for contractor", "Delay of material and tools Work on hold in other areas", "Increase in contractor’s overhead Demolition and re-work" and "Delays in payment to contractor". 6.4. Finding Prevention Certainty of the Change Request Impacts The third dimension of the survey is aimed to find the strong beliefs and practices of the construction industry of

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