## 4 Conclusions  
This study was conducted from the effort to provide the means to improve the existing waterproofing methods for pavement technologies for bridge deck surfaces. A double-sided bonding composite waterproofing sheet that can be applied to both APC and LMC pavement layers used on the bridge deck was proposed as a new waterproofing material, and its physical properties and applicability were verified in accordance to KS standard test methods. The conclusion of this study is as follows:  
1. For the purpose of preventing water leakage to ensure long-term durability of concrete bridges, a double-sided composite waterproofing sheet manufactured by laminating an asphalt compound layer and a modified acrylic emulsion layer on both sides with a non-woven fabric as the central material was proposed as a new bridge surface waterproofing material. As a result of measuring the resistance performance of deterioration factors such as temperature change, chemical influence, crack behavior, and water pressure for the newly proposed waterproofing sheet, according to the KS test method related to the waterproofing material for bridges, it is confirmed that the performance exceeds the KS quality standard;
2. As a result of evaluating the applicability of this waterproofing sheet when used with the APC pavement, it is confirmed that the material exceeds the performance requirement outlined in the KS standard by at least 8% and at most 130% in various performance items. Therefore, the waterproofing sheet proposed in this study is expected to exhibit stable waterproof performance even when applied to the APC pavement. In the case of LMC pavement, it is verified that the material exceeds the performance requirements outlined in the KS standard, at most, by about 320% in various performance items;
3. Comparing the results of using this waterproofing sheet for APC and LMC pavements, the performance is shown to be relatively higher with the LMC pavement, and it is  
Figure 9: Individual comparison of physical property evaluation results of waterproofing sheets in APC and LMC pavement layers.  
predicted that this result is due to the difference in the waterproofing layer adhesion caused by the difference in the properties of the waterproofing sheet material and the pavement material.  
As it stands, the double-sided bonding waterproofing sheet is verified as feasible for use as an option for waterproofing materials in bridge surfaces, regardless of the type of APC or LMC pavement. However, as experiments conducted in this study are limited to performance evaluation and standard requirements of Korean standards, further investigation is required before this material can be certified as viable for use in the international setting.  
Conceptualization, H.K., K.O., K.A., S.O., B.J. and X.H.; methodology, H.K., K.O. and S.O.; experimental plan, H.K., K.A., K.O., S.O., B.J. and X.H.; formal analysis, investigation, resources, data curation, H.K. and K.O.; writing--original draft preparation, H.K., K.O., K.A., S.O., B.J. and X.H.; writing--review and editing, S.O., B.J. and X.H.; supervision, S.O., B.J. and X.H.; project administration. All authors have read and agreed to the published version of the manuscript.  
This research was funded by research support program of Seoul National University of Science and Technology in 2021.  
Not applicable.  
The authors declare no conflict of interest. The founding sponsors had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, and in the decision to publish the results.