Standard laboratory tests were performed as part of a routine comparison of the two sealant binders and to augment the exterior and accelerated weathering data. Results are presented in Table 5 and Fig. 12. Adhesion and Joint Movement Performance-The acrylic sealant has excellent wet and dry peel adhesion to mortar, with no adhesive failure and […]
Рубрика: Durability of Building and Construction Sealants and Adhesives
Accelerated Weathering
To assess their usefulness in predicting real world weathering results, the sealants exposed in the El Paso warehouse exposure were also subjected to several accelerated weathering tests. Results are presented in Tables 2-4 and in Figs. 8-11. Weathering of Plaques in Xenon Arc and Fluorescent UV Weathering Devices — The results of the accelerated weathering […]
Results and Discussion
Tilt-Up Warehouse Exposures Early Observations-The applicator found that the acrylic sealant needed to be handled somewhat differently than the polyurethane sealants that he was used to working with. As mentioned earlier, the acrylic sealant sent to the job site was not optimized for application properties. The applicator, in fact, found that the acrylic sealant was […]
Laboratory Testing
To complement the exterior and accelerated exposures described above, three key ASTM C920-05 tests were run. These included adhesion, joint movement testing, and hardness. Adhesion to concrete mortar was tested according to ASTM C794-06 [8], with dry adhesion being tested after the initial 3 weeks of cure and wet adhesion after additional 1 week of […]
Accelerated Weathering
In addition to the warehouse exposures described above, the durability of the two sealants was also evaluated using standard accelerated weathering procedures and ASTM C1519-04, Standard Practice for Evaluating Durability of Building Construction Sealants by Laboratory Accelerated Weathering Procedures. Weathering of Plaques in Xenon Arc and Fluorescent UV Weathering Apparatus-Specimens for accelerated weathering were laid […]
Tilt-Up Warehouse Exposures
A tilt-up warehouse in El Paso, TX, was renovated in the Spring of 2005. As part of this renovation, the failing 20 year old sealant used in the original construction was removed and replaced with the acrylic and polyurethane sealants described above. To directly compare performance, these two sealants were applied in alternating joints around […]
Experimental Methods
Sealants A high performance acrylic sealant and a high performance polyurethane sealant, both conforming to the ASTM C920-05 Class 25 specification, were chosen for this evaluation. The polyurethane sealant was specified by the moisture-proofing contactor as part of a commercial restoration project. A two part polyurethane was chosen due to the low humidity in El […]
Field Performance and Accelerated Weathering of High Performance Acrylic and Polyurethane Sealants for Tilt-Up Applications
ABSTRACT: To demonstrate the suitability of high performance acrylic sealants to low rise industrial construction applications, a laboratory prepared high performance acrylic sealant was compared to a commonly used, commercially available two part polyurethane sealant. The centerpiece of this comparison is an exterior exposure in El Paso, TX, in which the two sealants were professionally […]
Comparison between Water Penetration Test Results of Vertical and Horizontal Joints
A comparison was made between water leakage through deficient vertical and horizontal joints as shown in Fig. 19. The results reflect leakage rates of joints subjected to a water deposition rate of 4 L/(min-m2). The Y-axis provides the rates of leakage (L/min) across the horizontal joint; that of the X-axis for the vertical joint. Results […]
Water Penetration Test Results for Horizontal Joint
Evidence of water penetration at the horizontal joint is given in Fig. 15 and Fig. 16. A view of water entry along the interior side of the joint is shown in the photo of Fig. 14; water is seen to be pooling on the surface of the interior of the joint but ultimately made its […]