Research on Interface Management of General Contracting Projects ()
1. Introduction
The general contracting mode of the project has the advantages of realizing the integrated management of design, procurement and construction under one main body, as well as the in-depth crossover of various specialties in the process of project construction, so as to better ensure the control of the progress and cost of the project. The engineering construction industry has received more and more attention. At the same time, in the process of solving the general contracting problem, it is often found that the root cause of most problems is the improper handling of the interface problem [1]. Therefore, the effective control of the interface problem is of key significance for the smooth completion of the general contracting project. This paper studies the influencing factors of the interface management of the general contracting project. Combined with the characteristics of the general contracting project, the factors that affect the interface management of the general contracting project are analyzed by factor analysis and fuzzy evaluation to clarify the key influencing factors. And put forward improvement suggestions for key factors, which provides a good idea for the future interface management of the industry.
The advantage of the project general contracting mode is to realize the integrated management of design, procurement and construction under one main body, as well as the in-depth crossover of various specialties in the process of project construction, so as to better guarantee the construction of the project. Control the schedule and cost of the project. The engineering construction industry has been paid more and more attention. At the same time, in the process of solving the general contracting problem, it is often found that the root cause of most of the problems is improper handling of the interface problem [2]. Therefore, the effective control of the interface problem is of key significance to the smooth completion of the general contracting project. This paper studies the influencing factors of interface management of general contracting projects. Combined with the characteristics of general contracting projects, the factors affecting the interface management of general contracting projects are analyzed through factor analysis and variance analysis, poor information processing ability, design work that ignores buildability, Security incident, too much intervention by the owner, use of new technologies, new materials and new processes in construction, uncertainty and changes in the surrounding environment and six key factors affecting the interface management of general contracting projects are proposed. The project provides theoretical ideas to better solve interface problems.
2. Interface Management Theory
The definition of the word “interface” in Chinese is the contact surface between two objects or components, but the interpretation in English is not the same. Some theories believe that the interface refers to the contact surface between two objects, some scholars believe that the interface refers to the boundary or interface between entities, and some people think that the interface is the mutual relationship and function of two individuals. The term first appeared in the field of engineering technology, and it is a description of the contact surface that is naturally formed in the process of mechanical equipment. Later, it was gradually cited by scholars in other fields. To understand the interface theory from the perspective of management, its connotation Both the extension and the extension have been expanded to a certain extent, which can not only describe the connection status of different departments, but also reflect the handover status between different processes and procedures, and even describe the relationship between people and things [3]. The interface was formally introduced as an independent study in the field of management science at a relatively late time. It was originally the engineering field term “interface management” cited by scholars when they analyzed the barriers and causes of interaction between traditional R & D and marketing departments. In the early research on interface by domestic scholars, Guo, Q. et al. believed that improper handling of the interface between research and development (R & D), marketing and production would lead to a low conversion rate of scientific and technological achievements and a low level of innovation [4]. The Great Wall Enterprise Strategy Research Institute explained the definition of interface in the early stage, and divided the interface into three levels: inter-enterprise (interface 1), intra-departmental (interface 2), and intra-departmental unit (interface 3) [5].
3. Research on Influencing Factors
In this paper, the research methods of the influencing factors of interface management include literature research method, questionnaire survey method and factor analysis method (Figure 1).
3.1. Survey Design
Generation of Initial Items
The scale was developed on the basis of literature research, the results of expert interviews, and this study. The initial scale mainly includes basic demographic variables and factors that affect the interface management of EPC general contracting projects. It is mainly enumerated by looking for the influencing factors that have appeared in the literature in domestic and foreign literature databases.
Searches for “interface management” and “EPC project interface management” in Chinese databases such as CNKI and Wanfang, as well as keywords such as “interface management” and “EPC interface” in foreign language databases such as ASCE and Web of science, for relevant literature, 50 Chinese and foreign literatures were obtained by further screening the references by quickly browsing the abstracts and key words of the literature. Select 20 of them for study, extract 120 influencing factors that affect the interface management of EPC projects, and select 34 of them shown in Table 1.
The first part of the questionnaire is to make statistics on the basic characteristics of the respondents, including the respondents’ gender, age, education level, work unit, job position, the number of participating EPC projects, and working years. Among them, the working years, jobs, and the number of participating EPC projects mainly refer to Liu Jiannan’s research on the key success factors of UHV project interface management. In addition, it also refers to the partial design of demographic variables in the questionnaire on residents’ waste management behavior by Chung et al. [6]. And Vu, Wang, Min, et al. Influence of financial factors on international general contracting projects on project schedule delay [7].
When designing the items of the second part of the evaluation of influencing factors, we mainly refer to the research of Wang and Ling [8]. At the same time, taking into account that some expressions do not conform to the habits of my country’s engineering industry, some modifications have been made to the naming of processes, etc. In addition, the questionnaires of foreign scholars generally have many items, and the questionnaires are very long. Considering that the length of the questionnaires will affect the recovery rate of the questionnaires, this study conducted a preliminary questionnaire within the research group to judge the semantics of the items and the questionnaire. Fill in the comfort.
The evaluation of the influencing factors in this study adopts the 5-point Likert design, and the respondents are asked to evaluate the content of each item according to their actual situation. “2”, “3” for “moderate impact”, “4” for “moderate impact”, and “5” for “severe impact”.
3.2. Descriptive Statistical Analysis of Basic Characteristics of Samples
3.2.1. Sample Gender Analysis
According to the gender structure, there are 225 males, accounting for 82.7%, and 47 females, accounting for 17.3%. The proportion of males is significantly higher than that of females. This ratio also reflects well that there are far more male employees than females in the construction engineering industry.
3.2.2. Sample Age Analysis
In terms of age level, the group aged 25 - 35 accounted for the largest proportion, accounting for 43.4%, followed by the group aged 46 and above, accounting
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Table 1. Initial influencing factors.
for 26.8%, and the two combined accounted for 70.2%. The remaining 16 - 24 years old and 36 - 45 years old accounted for 7% and 22.8% respectively. It can be seen that the respondents are mainly young and middle-aged people aged 25 - 35. On the one hand, this age group is in a stage of just graduating and career advancement, and secondly, this age group has relatively good physical fitness, can withstand the work intensity of the engineering industry, and can also bring them considerable income.
3.2.3. Sample Educational Attainment Analysis
Judging from the educational structure of the sample, there are 155 people with bachelor degree, accounting for 57% of the total sample, followed by college degree, with 59 people, accounting for 21.7%; the rest are doctor or above, master, high school and below, accounting for 7%, 18%, and 2.6%, respectively. It can be seen from this that the total proportion of bachelor degree and above is 75.7%, which shows that the current employees in the engineering industry are generally highly educated and have a relatively high cultural quality. This is due to the development of engineering technology, and more and more high-tech equipment and processes are applied in the engineering industry, so higher requirements are placed on the cultural quality of employees.
3.2.4. Sample Work Unit Type Analysis
From the distribution of the types of units where the samples are located, the most are from construction units, with a total of 128, accounting for 47.1%; followed by 31 cost consulting units, accounting for 11.4%; the rest of the owners, design units, supervision units, procurement units, government departments, For details of other consulting units, universities or scientific research institutions, and general project contractors, please refer to Table 2. This shows that the personnel from the construction unit far exceed other units, which is also in line with the actual construction process. In any construction project site, the personnel from the construction unit always account for the majority.
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Table 2. Respondent basic information.
3.2.5. Sample Job Type Analysis
From the distribution of the sample positions, there are 90 enterprise managers, accounting for 33.1%, followed by professional technicians and project managers, accounting for 26.5% and 24.3%, respectively. The rest are government department managers, researchers from universities or research institutes, and other personnel, accounting for 2.6%, 5.9%, and 7.7%, respectively. The samples came from front-line professional technicians and project managers, accounting for 83.9% in total. Such samples are directly involved in the project construction and provide good support for the authenticity of the data.
3.2.6. Quantity Analysis of Samples Participating in EPC Projects
This questionnaire survey is a factor affecting the interface management of EPC general contracting projects, so the number of respondents participating in EPC projects is investigated. It can be seen from Table 2 that 176 persons have participated in the EPC general contracting project, accounting for 64.7% of the total, and the remaining 35.3% of the surveyed persons have not directly participated in the EPC project. In addition, the largest number of people participated in 1 - 3 EPC general contracting projects, with a total of 154 people, accounting for 56.6% of the total. This shows that with the gradual promotion of the EPC general contracting model, more and more construction processes in my country use the EPC general contracting method for construction.
3.2.7. Sample Working Years Analysis
Judging from the working years of the investigators, there are 84 working years from 1 to 5 years, accounting for 30.9% of the total; More than 112 years, accounting for 41.2% of the total. According to the survey results of working years, it can be shown that those who participated in this survey are practitioners with certain work experience.
3.3. Descriptive Statistical Analysis of Influencing Factors
From Table 3, it can be seen that in the evaluation of 34 factors, the evaluation score of “1” has a lower weight among all factors, the evaluation score of “3”, and “4” has a higher weight among all factors, and these scores provide support for the analysis of variance below.
After calculation, the average evaluation score of all factors is 4. The evaluation score for such factors as excessive intervention by the owner delayed payment of the project payment by the owner, incomplete design drawings, many errors in the design drawings, low contract price, lack of effective management
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Table 3. Evaluation of various influencing factors.
and unified command, etc. exceeded 3.8 from Table 4. For the analysis of individual factors, factors such as delay in payment of construction costs by the owner, low contract price, many errors in design drawings, lack of effective management and unified command and other factors are rated as having the highest proportion of serious impacts. Looking at the results from the perspective of factors, it reflects that the interface management of EPC general contracting projects is seriously affected by the above factors, so it lays a foundation for the specific analysis of the influencing factors below.
4. Conclusions
4.1. Variance Analysis of Individual Characteristics and Influencing Factors
After exploratory analysis, 34 influencing factors were classified and divided into six categories of influencing factors. According to the contribution of each influencing factor, a key influencing factor was extracted from each type of factor, and the “inter-organizational information communication quality” was extracted. The “inter-organizational information communication quality” extraction factor “poor information processing ability”; “designer’s work quality” extraction factor “design work neglects constructability”; “constructor’s work quality” extraction factor “safety accident”; “changed” extraction factor “too much intervention by the owner”; “the use of new technologies or new materials” extraction factor “the use of new technologies, new materials, new processes in construction”; “uncertainty of the environment or resources” extraction factor “more uncertainty
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Table 4. The average of each factor.
and changes in the surrounding environment”. The following is a variance analysis of the six influencing factors of EPC project interface management.
4.2. Analysis of Variance between Gender and Influencing Factors
It can be seen from Table 5 that the significance levels of the six factors are all greater than 0.05. Through the homogeneity test of variance, the gender differences are analyzed below.
From the data in Table 6, it can be seen that “the information processing ability is poor, the design work ignores the constructability, safety accidents occur, new materials, new technologies and new processes are used in construction, and there are many uncertainties and changes in the surrounding environment” The significance level is greater than 0.05. The significance level of “too much intervention by the owner” is lower than 0.05, indicating that the influence of this factor on the interface management of EPC projects is different for different genders. As can be seen from Table 7, in terms of the average score of the factor of “too much intervention by the owner”, men (3.90) are significantly higher than women (3.43). Compared with males [7], the scores of female practitioners with “too much intervention by the owner” are relatively low, and they are considered to have a low degree of influence on interface management.
4.3. Variance Analysis of Educational Level and Influencing Factors
From Table 8, it can be seen that the significance levels of “poor information processing ability”, “neglecting constructability in design work”, “too much intervention by the owner”, and “use of new materials, new technologies and new processes in construction” are all greater than 0.05, through the homogeneity test of variance, the following analysis of the differences in education levels.
It can be seen from Table 9 that the significance of the factor of “too much intervention by the owner” is less than 0.05, indicating that this factor has significant differences among people with different educational levels. From Table 10, it can be seen that on the factor of “too much intervention by the owner”, the
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Table 5. Variance homogeneity test of gender.
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Table 7. Descriptive statistics of gender.
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Table 8. Variance homogeneity test of education level.
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Table 9. One-way ANOVA of education level.
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Table 10. Descriptive statistics of education level.
average score is approximately inversely proportional to the increase in educational level, that is, the employees with lower educational level think that “too much intervention by the owner” has a more serious impact on interface management. From Table 2, it can be seen that 75% of the respondents have a bachelor’s degree or below. This data shows that the current education level of employees in the construction industry is mostly bachelor’s degree and below. Due to different learning environments, people with different education levels may be more likely to have theoretical knowledge. He has a relatively thorough understanding and will respond patiently to the owner’s suggestions through his professional knowledge or experience.
4.4. Variance Analysis of Work Unit and Influencing Factors
From Table 11, it can be seen that “the ability to process information is poor”, “the design work ignores the constructability”, “the owner intervenes too much”, “the use of new technologies, new materials, and new processes in the construction”, “the unfavorable environment of the surrounding environment” The significance level of “certainty and more variation” is greater than 0.05, which is regarded as passing the homogeneity test of variance. The differences between the types of work units are analyzed below.
From Table 12, it can be seen that the significance level of the two factors of “ignoring constructability in design work” and “too much intervention by the
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Table 11. Variance homogeneity test of employer.
owner” is less than 0.05, indicating that these two factors have significant differences in the population of different work units. The average score of the “design work neglects constructability” supervision unit is up to 4.33, followed by the average scores of other consulting units and general engineering contractors. In an EPC project, the general contractor usually purchases the supervisory unit and the consulting unit, which is in a juxtaposed relationship with the design unit, so this type of unit is more sensitive to the factor of “ignoring constructability in design work”. Finally, as the overall leader, the general contractor is at a high level of sensitivity to the work of each subcontractor. For “too much intervention by the owner”, the average score of the general contractor is 4.45 and the lowest is 3. The general contractor of the project directly signs the general contract with the owner. The owner frequently intervenes in the project, which affects the progress of the project. The general contractor, as the general person in charge of the project, must bear the schedule and cost risks. Therefore, general contractors are more sensitive to this factor.
Acknowledgements
This research was supported by Anhui Cindare Real Estate Development Co., Ltd.