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Although epoxy adhesives have been used for many years in the construction industry, they are now being used to an increasing degree in precast prestressed concrete applications. This is especially evident in segmental bridge construction.
The author reviews the properties of structural adhesives and lists the important criteria for selecting epoxy adhesives.
In particular, he emphasizes the importance of obtaining reliable data on creep deformation, heat stability, and moisture resistance.
The properties of epoxies are greatly influenced by variations in temperature.
The test results of a comprehensive laboratory program on the creep behavior of epoxy mortars are presented.
Suggested items for specifications are listed together with several pointers in applying the adhesive.
For example, it is very important not to exceed the allowable time period between mixing and epoxy application.
Some suggestions are given on field testing and items needed to be tested.
Finally, the application of epoxies to two specific bridge projects is described.
Epoxy resins have been employed in the construction industry for many years. For example, they have been used as anti-corrosion coatings, indus-trial flooring, interlayer sealing mem-branes, anti-skid surface dressings, ad-hesives, injection and grouting systems.
There are, therefore, great variations in the properties required of the binder or the ready-for-use products in the dif-ferent types of applications.
When epoxies are used to transmit loads, they must possess very unique properties since both the stability and durability of a structure must be guar-anteed over its life span.
Segmental precast concrete bridges fit into this category. For some practi-cal applications of epoxy adhesives in segmental construction refer to the end section of this paper.

CRITERIA FOR SELECTING EPDXY ADHESIVES
TEST RESULTS
SUPPLEMENTARY CONSIDERATIONS
SUGGESTED SPECIFICATIONS
POINTERS IN APPLYING THE ADHESIVE
FIELD TESTING
APPLICATIONS

The epoxy adhesive was applied to adjoining segment surfaces with wood-en spatulas. During this operation the adjoining segments are about 30 to 40 cm (approx. 12 to 16 in.) apart.
In general, only two men are re- quired to apply the epoxy. However, on the Rio-Niteroi job, two men were employed on the deck and four to six men inside the segment. It took about 45 mintes per segment to mix and apply the epoxy (including the in-itial post-tensioning operation). How-ever, on other jobs this time has been some what reduced.

Chillon Viaduct

The other noteworthy project using epoxy bonded segments is Switzerland's Chillon Viaduct, located near the his-toric Chillon Castle. In such a scenic setting it was important to leave the natural environment unscathed. Seg- mental construction proved to be an ideal mode of erection.
Fig. 9 shows a construction man, on a finished deck, manually applying an epoxy adhesive to a new segment as it is gradually lowered into place. On the Chillon job, https://www.51lunwen.org/CivilEngineering/ the mixing and applica-tion of the epoxy (including the initial post-tensioning) took about 30 minutes.
In Fig. 10 the adhesive has been ap-plied to the far side of the segment.
Simultaneously, the tendons and stress-ing equipment are being readied for the initial post-tensioning oper本论文由英语论文网提供整理，提供论文代写，英语论文代写，代写论文，代写英语论文，代写留学生论文，代写英文论文，留学生论文代写相关核心关键词搜索。