Waterproofing membrane systems

Waterproofing membrane systems are available as either postapplied or preapplied products for use in either positive-side, negative-side, or blind-side applications [13,15]. 

With or without perforations, may be used with asphalts conforming to Specification D312 requirements in constmction of BUR, and Specification D449 requirements in membrane system of waterproofing. Felts covered by this specification are Type I (No. 15 asphalt felt) and Type II (No. 30 asphalt felt). 

A composite concrete slab or a stressed-skin system can also provide a roof diaphragm, but the latter may severely restrict the provision of subsequent roof penetrations. Concrete roof slabs are unusual, due to the greatly increased mass over the more normal metal decking/in-sulation/waterproof membrane or insulated metal decking options. 

Samples to be tested were kept more than 61 hours in the temperature condition of 23°C and relative humidity of 50% this corresponded to the requirements of SN-ISO 291. Sample stripes were taken from the system composed of protective mat, waterproofing membrane, and the underlying polymeric geotextile polymer bedding the length of the strips amounted to 250 mm. The strips were bonded at discrete end points according to the actual conditions of waterproofing systems. 

The hammer survey (or chain drag used on decks) is usually quicker, cheaper and more accurate than the other more sophisticated alternatives such as radar, ultrasonics or infrared thermography. However, these techniques do have their uses for instance in large scale surveys of bridge decks (radar and infrared) of waterproof membranes or other concrete defects (ultrasonics and radar). A vehicle mounted radar system is show in Figure 4.4a. The more sophisticated techniques may be needed for deep delaminations and are discussed later in this chapter. 

However, the lack of waterproof membranes is why there are many cathodic protection systems are on bridge decks in Canada and the northern states of the United States, where membranes were not widely used, while many European systems applied to bridges are on the support structure. Membranes and cathodic protection are not easily compatible as gases are evolved by CP systems which could be trapped by a waterproofing system. This is discussed in Chapter 7. 

There are several reasons for EBECR becoming the protective system of choice in the United States and Canada for reinforcing steel exposed to chloride attack. One is the reluctance to nse waterproof membranes on bridge... 

Thare are several reasons for FBECR becoming the protective system of choice in the USA and Canada for reinforcing steel exposed to chloride attack. One is the reluctance to use waterproof membranes on bridge decks as they are difficult to install properly and to monitor both for correct installation and for performance after installation. The preference for a very low maintenance bridge deck led most state DOTs and the Federal Highway Administration (FHWA) to look for alternative protective systems on all bridges exposed to chlorides from the sea or from deicing salt. 

To meet these desirable properties, the appropriate polymer to consider would be ethylene - propylene-diene terpolymer (EPDM). In the manufacture of a cost effective, impermeable membrane system, EPDM rubber is the right choice as a discreet material for improved waterproofing and protective lining applications in roofing and other uses in the construction sectors [125]. 

Rubber based waterproofing systems are typically based on styrene-butadiene copolymers and SBS resins while acrylic and styrene-acryHc dispersions are employed in most flexible one-component and two-component cementitious membrane systems. 

Today, in principle, two different systems of cementitious waterproofing membranes or slurries are available ... 

Development of polymer-modified cementitious membrane waterproofing systems using polymer-modified paste and mortar [68]... 

Careful detailing is needed to avoid water and chlorides getting under the edges of the membrane. It is also essential to ensure that the deck and membrane drain properly, with adequate waterproofing around drains and with no ponding. The drainage system from the deck must not then dump salt laden water onto the substructure. 

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