Decalcification of Cement Concrete Structures and Dissolution of Bitumen by Windshield Washer Fluid.

Abstract

A new phenomenon of decalcification of the cement concrete structure and dissolution of bitumen in bituminous pavement is described, caused by the surfactants included in the windshield washer fluid of automobiles. Decalcification occurs in cement concrete samples in the laboratory even at low concentrations of surfactant of 25 ppm. Recently, foam with fine bubbles have been observed in the water on pavement just after rain worldwide. The decalcification reaction was identified as an ion exchange reaction between the calcium ions Ca2+ in the concrete and Na+ in the surfactants using the electron spectroscopy for chemical analysis (ESCA) method. Bitumen was also found in the decalcified cement concrete, from which the Ca component had dissolved out gradually with time.

Damage to cement concrete pavements due to exposure to organic compounds in a cold region

“…Three powder samples (mortar powder, aggregate powder, and scraped-out powder collected from concrete Type B), were extracted in a Soxhlet extractor. The samples were first extracted by methanol for 24 hours, and the residue was then extracted using chloroform for 24 hours [17]. The organic compounds were identified using GC-MS (gas chromatography-mass spectrometry) [18] and [19].…”

“…Based on this it was decided, to use polyoxyethylene nonylphenyl ether sodium sulfate, an anion surfactant, in the immersion experiments, as this would cause the elution of the calcium in the cement concrete, which would turn the solution cloudy, showing when calcium salts were generated [17] and [20].…”

Water Accumulation and Behavior of Surfactant Associated with Moisture Permeation in Bituminous Pavement on Concrete Deck Bridge

“…Poly-oxyethylene nonylphenylether sodium sulfi te is a typical surfactant produced in large quantities. Surfactant is recognized as one of the chemicals accumulated in social infrastructure widely such as pavements and bridges 5) . Anionic surfactant (n-C9H19 _ C6H4 _ O(CH2CH2O)6 _ SO3Na) with pH 9-10 was used in this study as an entraining chemical with moisture permeation.…”

“…The powder of the concrete slab was used for solvent extraction by the soxhlet method to identify the chemical components 5) . The powder sample was preliminarily extracted with methanol to remove inorganic components.…”

“…As extrinsic chemicals accumulate in concrete structures, surfactant has been detected in several concrete bridge structures 5) . The source of surfactant is supposed to be window washer fl uid or suspended particulate matter (SPM) 5), 6) .…”