Mutual Correlation Between Softening Point and Flow Resistance at Elevated Temperature According to Bitumen Mass in Bitumen Sheets

3rd World Multidisciplinary Civil Engineering, Architecture, Urban Planning Symposium

土木建筑工程;文学

Plachy, Jan^1 ; Vysoka, Jana^1 ; Vejmelka, Radek^1

Institute of Technology and Business in eské Budjovice, Department of Civil Engineering, Okruní 517/10, eské Budjovice

370 01, Czech Republic^1

关键词: Building construction;    Elevated temperature;    Isolating materials;    Laboratory measurements;    Mutual correlations;    Statistical evaluation;    Temperature values;    Underground construction;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/471/3/032078/pdf
DOI  :  10.1088/1757-899X/471/3/032078

学科分类：土木及结构工程学

来源: IOP

【 摘 要 】

Bitumen sheets are isolating materials that are used in the building construction, primarily as roof waterproofing, vapour barrier and waterproofing of the substructure. For civil engineering they are applied as the isolation of concrete bridge decks and they are used as the main waterproofing for underground construction. Currently, bitumen sheets mentioned above are modified by polymers of elastomer and plastomer. In the places where the bitumen sheets are exposed to UV radiation or to high temperature, the manufacturer is, according to the product standards, required to declare the flow resistance at elevated temperature. This paper deals with the investigation of the interdependence between the flow resistance at elevated temperature and the softening point of the bitumen matter in these bitumen sheets. In practice, the results of this dependence are often used in the production of bitumen sheets during the inter-operative check, where the softening point value determines the value of the flow resistance at elevated temperature. This allows to determine, whether the produced bitumen sheets will fulfill the values declared by the manufacturer with advance. Since the test for detection of the value of the softening point takes in average 30 minutes then it is possible to react quickly and efficiently during the production and to make the appropriate corrections. Reinforced bitumen sheets which are used for waterproofing of the isolation of concrete bridge decks were selected as the samples from various manufacturers. In practice, this aforementioned dependency is often cited but it is not explicitly documented by a sufficiently large number of samples. The authors of this article found during the previous research that the dependence is influenced by the temperature value - the higher is the temperature, the more obvious is the dependence. For this reason, it is very evident in the case of bitumen sheets modified by polymers of the plastomeric character. The hypothesis, that there exists some relationship between the flow resistance at elevated temperature concerning to bitumen sheets and the softening point of the bitumen matter, was confirmed only partially. The aim of the paper is to confirm or refute the hypothesis even for materials modified by polymers of elastomeric character. For this reason, the number of bitumen sheets modified by polymers of both plastic and elastomeric character was increased. Results were formulated based on the statistical evaluation of data obtained from laboratory measurements.