Minimization of Waste Generation at Construction Sites

Waste has been recognized as a major problem in the construction industry and its effects on working efficiency as well on general economy of country. Waste generation results from numerous factors at different stages of construction projects. The main objective of this paper is to identify the most significant causes of waste in construction projects of Sindh. This study is based on questionnaire survey investigation. Total seventy-three (73) respondents having construction site experience, participated during data collection. The gathered data was assessed through statistical method with help of Average indexing (A.I) technique. Findings of analyzed questionnaires present that, unsuitable methods of material storage, worker’s mistakes, poor management system at site, effect of sub surface ground conditions, excessive use of construction material, inexperienced constructor hire for construction project work, poor site layout, poor coordination among the construction stakeholders, improper planning schedule of project by the constructor and problem between main constructor and sub-constructor are major construction waste issues in Sindh region. Keyword-Construction Projects, Waste Generation, WasteMinimization.

issues of construction waste generation, as per the research findings, poor site supervision and management, poor planning and scheduling, inexperience hired staff, errors and mistakes occurs in designs and mistakes during construction are essential factors responsible for construction site waste.Recently, in Iran a research discoveredthe major causes of construction waste occurrence at sites i.e.lack of skills, lack of knowledge of demolition, use of old methods of construction, low quality material, inappropriate method for shipment and frequent demolition [13]. Errors in design, frequent changes in design, inexperience workers, weather effect and failure of equipment at site during construction works are most essential causes of construction waste in under developed regions of world [14]. The literature is rich in different regions globally related to construction waste, however this research study based on identifying the waste generation factors in Sindh region, which fulfill the major gap in literature.
III. DATA COLLECTION AND ANALYSIS A quantitative method was used for conducting questionnaires with experienced personnel involved in construction projects. On the basis of identified factors, the targeted respondents were asked about level of significance of these factors in relation to Sindh region's construction projects.Level of significance of these factors weremeasured on an ordinal scale.A five point Likert's scale was adopted for collection of data through questionnaire survey.Where "1" describes to not significant and "5" describesto extremely significant. Analysis of factors was done with Statistical Software Package (SPSS) version 20. After analyzing the gathered data, the rank of each factor was decided on the basis of average index values. Literature reveals that average index method formula has been used in data analysis [15].

IV. RESULTS AND DISCUSSION
The data was collected through a questionnaire survey. Construction practitioners such as clients, consultants and constructors of Sindh region were the targeted respondents for this study. A total of 110 questionnaires were distributed among targeted respondents. Seventy three (73) questionnaires were received and valid for data assessment purpose. Figure 1 and 2 present the response of received questionnaires and experience level of respondents respectively.The collected data was analyzed to find out the most significance waste generation factors in construction projects of Sindh region. Average index (A.I) value of every significance factor of construction waste with its rank is shown in Table 1.  Worker's mistakes 4.17 2 3 Poor management system at site 4.14 3 4 Effect of sub surface ground conditions 4.10 4 5 Excessive use of construction material 4.10 4 6 Poor site layout 3.86 5 7 Poor coordination among the construction stakeholders 3.83 6 8 Improper planning schedule of project by the constructor 3.77 7 9 Problem between main constructor and sub-constructor 3.77 7 10 Poor weather conditions 3.66 8 11 Poor storage of construction material 3.63 9 12 Delay in arriving of workers and material at site 3.60 10 13 Damage

V. CONCLUSION AND SUGGESTION
The main target of this research work is to identify the construction waste factors in construction projects of Sindh. The significance level of these causative factors wasdetermined througha questionnaire survey. The respondents were targeted from Sindh region with rich site experience of construction. Average index technique was used to examine the level of importance of causative factor and then to decide their rank. The results of the study identified the top most significance factors of construction waste in Sindh region projects. Unsuitable methods of material storage (UMMS), worker's mistakes (WM), poor management system at site (PMSS), effect of sub surface ground conditions (ESSGC) and excessive use of construction material (EUCM) are major causes of construction waste generation. Therefore, the research concludes that, there is seriousnecessityfor minimizing the construction waste in Sindh region projects by reducing the identified major causes of this research work. On the basis of results,the authors provide following suggestions for construction practitioners to minimize waste generation in construction projects of Sindh.
1. Design a systematic method for construction handling and storage of materials. 2. Construction personnel should arrange meetings on daily basis and develop a path for improving communication and coordination among the stakeholders. 3. A fully authorized site supervisor/inspector must be hired and available at the site for monitoring, however a senior engineer must visit the site regularly to resolve the site issues. 4. Ground condition must be known prior to executionof work on site and work should be carried out as per engineer's direction. 5. Proper quantity estimation must be done and engineer at site must ensure the material utilization as per estimation. 6. Proper site layout plans be made by the constructor, which help the construction practitioners in resolving poor site layout issues before staring any work at construction site. 7. Construction players should develop a waste management plan system to minimize the waste. 8. All stakeholders should beaware about weather conditions of construction site.
ACKNOWLEDGEMENT The authors would like to thanks Mehran University of Engineering and Technology, Jamshoro, Sindh, Pakistan and Chairman of Civil Engineering Department for their continuous encourage and support in completing this research study.