A Research on the Prediction Model for the Unit Rate of Construction Formwork

Autor: Chi-ming Hsu, 徐啟銘
Rok vydání: 2005
Druh dokumentu: 學位論文 ; thesis
Popis: 93
In general, Taiwan construction companies “subcontract” to others, in which the calculation of labor costs are all based on the amounts of construction units, which result in the continuous ambiguity of the actual unit rate of each labor and each work in the industry. Therefore, the actual labor costs and required working time could not be truly controlled, and indirectly result in the failure of implementing schedule of construction management in Taiwan. Furthermore, it is known from expert interview that at this moment, the analysis of unit rate by each unit (architect, construction consultant company, construction company, and construction personnel) is based on the unit wages requested from subcontractor, and fill in the unit rate of unit price analysis form after convert to unit rate from daily wages. The advantage of this method is that unit rate is closer to the unit rate of contracted unit price, and more comply with the status of unit rate of practical working item, but has difference with practical unit rate. For the reason, through the results of literature review, expert interview and research inference, this research collects 5 types with total 30 influential factors that influence the unit rate of formwork, including “personal factor”, “knowledge and technological factor”, “environmental factor”, “technology and structure factor”, and “emotional factor”, to execute on-site questionnaire survey on the formwork construction personnel of building construction in Taiwan, and file the data obtained from testees first, and confirm the appropriateness of sampling of the scale by reliability and validity analysis. However, the attribute of every inner and outer evaluation factor of unit rate is different, and could divide to “factor could measure by numerical” and “factor could not measure by numerical”. Therefore, the correlation between each factor (ordinal variable and categorical variable) and correlation and influence of each factor on the unit rate of RC structure (Classify to wall, beam and stair structure according to the investigation of phenomenon feature) are analyzed respectively by correlation analysis, independent sample t-test, and one-way ANOVA, and analyze the possible influence on working ratio by different condition combination as the basis of independent variable to establish the quantity factor model (model established by numerical data) and prime factor model (model established by non-numerical data) of the prediction of unit rate with different attribute. After realized the influential factors and structure of unit rate of building formwork, based on the result, this research utilized quantity factor to make multiple regression analysis, and utilized prime factor to make quantified I analysis, and established the predicted quantity factor model and prime factor model of the working ratio of construction formwork, respectively (Classify to wall, beam and stair structure according to status quo). Finally is to discuss the difference and error rate between two models, and compare the R2 value of predicted model in each RC construction material and the error rate between the practical unit rate and predicted unit rate of model from the data of testee (5 random sampling); in which the compared results of R2 value in each model are “R2 value of wall construction material, quantity factor model is 58.4%, prime factor model is 77.5%), “R2 value of beam construction material, quantity factor model is 56.0%, prime factor model is 74.1%”, and “R2 value of stair construction material, quantity factor model is 70.4%, prime factor model is 84.2%”; the compared results of the error rate △ (%) between each model is, “ error rate △ (%) of wall construction material, quantity factor model 13.99%, prime factor model 10.19%”, “error rate △ (%) of beam construction material, quantity factor model 8.28%, prime factor model 7.32%”, and “error rate △ (%) of stair construction material, quantity factor model 8.83%, prime factor model 4.42%”. It is verified from the compared results that prime factor model is more accurate in the prediction of unit rate in formwork, and propose to the industry as the reference and application when predicting the unit rate of RC construction material in formwork. The achievement of this research could control the unit rate of each RC construction material in the formwork effectively through the prime factor model established in the research, and could be the effective and correct basis for construction consultant company, construction company and construction management consultant company to evaluate unit rate and computing working schedule while making construction quotation, and could also be the reference for the industry to evaluate the working efficiency of subcontractor.
Databáze: Networked Digital Library of Theses & Dissertations
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