Waterproof Membranes

Increasing Demand for Hydrated-Type Liquid- plied Membrane Waterproofing Materials (in Japanese), The Bosui Journal, 21(10) 43-46 (Nov. 1990)... 

Integral Waterproofings and Liquid-Applied Membrane Waterproofings Concrete roofdecks, mortar walls, concrete block walls, water tanks, swimming pools, septic tanks, silos, etc. 

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

Ballasting is an economical and quick system to secure an EPDM roof membrane. Waterproofing sheet is simply fitted over the flat roof or to a low slope, and covered with cleanly washed well rounded gravel with a diameter of 40-50 mm. Corners may be ballasted with suitable concrete slabs to prevent the sheeting from wind uplift and the perimeter can be fixed with contact adhesive. 

ASTM D5295 Standard guide for preparation of concrete surfaces for adhered (bonded) membrane waterproofing systems. 

Applications flame retardation, fuel cells, fuel hoses, medical (bene regeneration, stomach wall regeneration), membranes, waterproofing ... 

Guide for design of built-up bituminous membrane waterproofing systems for building decks... 

This test method is under the jurisdiction of ASTM Committee D-g on Roofing, Waterproofing, and Bituminous Materials and is the direct responsibility of Subcommittee D08.03 on Surfacing and Bituminous Materials for Membrane Waterproofing and Builtup Roofing. 

WATER - WATERPROOFING AND WATER/OIL REPELLENCY] (Vol 25) Waterproofing membrane... 

In modem PMR constmction, thermal iasulation that is unaffected by water or that can be kept dry ia some manner is required. Extmded polystyrene (XEPS) foam iasulation boards ate commonly employed (see Insulation, thermal). They ate placed on top of the waterproofing roof membrane, which is next to the deck. The iasulation should not be adhered to the membrane. Ballast at the rate of >48.8 kg/m (1000 lb/100 ft ) holds the iasulation ia place and offers protection from the sun. The iasulation joiats ate open and drainage must be provided. Various other materials, eg, patio blocks and concrete slabs, ate also used as sutfaciags and ballast. The extra weight imposes mote exacting requirements on constmction. 

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). 

Membrane Roofing. Many of the same types of materials used in membrane roofing are also used in waterproofing appHcations, because usually a membrane is needed to maintain the waterproofness of the foundation. They are used mainly on large commercial buildings. 

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. 

Pitched roofs. Pitched roofs are typically sloped at a minimum of 6° to ensure the weather resistance of lapped sheeting without sophisticated seals or a waterproof membrane. Portal frames are also more liable to snap through buckling at very shallow pitches. A pitched roof means a greater dead volume to heat, although there is additional space for high-level service distribution. 

Figure 6.15 A typical external waterproof membrane detail...

The roof must be able to shed water that falls on it, although it need not be waterproof in the sense of being a waterproof membrane structure. The roof surface is exposed to sun, wind and driven debris and must be resistant to erosion by the action of sunlight and the abrasive action of wind driven debris. In most cases the roof is insulated thermally to... 

At constant PBT/PTMO composition, when the molar mass of PTMO block is >2000, partial crystallization of the polyether phase leads to copolymer stiffening. The properties of polyesterether TPEs are not dramatically different when PTMO is replaced by polyethers such as poly(oxyethylene) (PEO) or poly(oxypropylene). PEO-based TPEs present higher hydrophilicity, which may be of interest for some applications such as waterproof breathable membranes but which also results in much lower hydrolysis resistance. Changing PBT into a more rigid polymer by using 2,6-naphthalene dicarboxylic acid instead of terephthalic acid results in compounds that exhibit excellent general properties but poorer low-temperature stiffening characteristics. 

Bentonite clay expands when moist to create a waterproof barrier. Bentonite is sold in various forms, including panels and mats. Bentonite is not as resistant to chemicals as the thermoplastic membranes, nor is it puncture resistant. The major flaw of bentonite as a radon barrier, however, is that it is only tightly expanded when wet. This is acceptable for a waterproofing material, but not for a gas barrier. 

Button cells consist of cathode and anode cans (used as the terminals), powdered zinc anode, containing gelled electrolyte and the corrosion inhibitor, separator with electrolyte, thin (0.5 mm) carbon cathode with catalyst and PTFE, waterproof gas-permeable (teflon) layer and air distribution layer for the even air assess over the cathode surface. Parameters of battery depend on the air transfer rate, which is determined by quantity and diameters of air access holes or porosity of the gas-diffusion membrane. Air-zinc batteries at low rate (J=0,002-0,01C at the idle drain and J= 0,02-0,04C at the peak continuous current) have flat discharge curves (typical curve is shown by Figure 1). 

Asphalt—mbber is mixed and applied to roadways by several techniques. In one method, mbber and asphalt are mixed at ca 175—220°C for one to two hours. The hot mixture is applied to the roadway and covered with a layer of stone chips to form a chip seal. The mbber cmmb consists of scrap tires ground into particles less than 2 mm in diameter. Rubber-modified asphalt is also used for waterproofing membranes, crack-and-joint sealers, hot-mix binders, and roofing materials. The mbber improves asphalt ductility and increases its softening point. The aggregate adhesive bond is stronger, and the asphalt lasts longer. Production of rubber-modified asphalt has increased from 405 t in 1970 to 27,000 t in 1980 (41). Typically, about 2 t of mbber is used for 1 km of roadway. If it is assumed that asphalt—mbber contains ca 25% mbber and 75% asphalt, the potential demand for scrap mbber would be ca 40,500 t/yr, or ca 2% of the amount available. 

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