Pervious concrete

About: Pervious concrete is a research topic. Over the lifetime, 2920 publications have been published within this topic receiving 27720 citations. The topic is also known as: porous concrete & permeable concrete.

Effect of field and laboratory curing on the durability characteristics of plain and pozzolan concretes

Abstract: The environmental conditions in the Arabian Gulf countries are classified as aggressive and severely corrosive. Field and laboratory studies have shown that concrete in this region should be designed not only for strength but also for durability. Utmost emphasis should be given to produce dense and impermeable concrete, to extend the service life of structures. In this study, concrete samples were prepared using various types of cements and fly ashes at various mix designs. The samples were cured in the field and in laboratory conditions. The permeability was determined by volume of permeable voids and absorption tests. The results showed that continuous water curing is necessary to obtain the least permeable concrete for both plain and pozzolan concretes. Irrespective of curing procedure followed, the fly ash concrete exhibited lower permeability than plain concrete for an initial test period of 7 days during curing. The fly ash concrete samples cured in the laboratory exhibited lower initial surface absorption than control concretes after 90 days of curing for all fly ash additions (10–40%) and cement factors (275–450 kg/m3) used.

Permeable additive for permeable concrete and preparation method of permeable additive

Abstract: The invention provides a permeable additive for permeable concrete. The permeable additive is characterized in that the permeable additive contains non-wood plant fibers having the capillary permeable function, and raw materials of the permeable additive are composed of, by weight, 50-70 parts of the non-wood plant fibers, 25-35 parts of cellular materials, 3-5 parts of hydrosol, 0.8-1.2 parts of dispersant, 0.6-1.0 parts of water reducer and 0.5-1.0 parts of an active agent. The non-wood plant fibers serve as the main composition body of the concrete additive, and modification treatment is conducted, so that the porosity, water permeation amount and hydrophilicity of the non-wood plant fibers are improved, when the permeable additive is used for preparing the permeable concrete, no or few coarse aggregate can be used, after the permeable additive and the concrete form a firm entirety, the porosity and water permeation amount of the permeable concrete are improved, meanwhile, strength and abrasion resistance of the concrete are guaranteed, and the permeable additive can be applied to high-loading road concrete such as urban rods and expressways.

Investigations on Some Properties of no-Fines Concrete

Abstract: No-fines concrete is a form of lightweight porous concrete, obtained by eliminating the sand from the normal concrete mix. The advantages of this type of concrete are lower density, lower cost due to lower cement content, lower thermal conductivity, relatively low drying shrinkage, no segregation and capillary movement of water, better insulating characteristics than conventional concrete because of the presence of large voids. This paper presents the results of an investigation to determine the performance characteristics of concrete mixes made without fine aggregates. Single sized course aggregates fraction 13.5-19 mm from Kgale Hill quarry and Ordinary Portland cement were used in the experiments. Concrete mixes with different aggregate/cement and water/cement ratios were prepared to find an optimum mix yielding the highest strength. The influence of the above factors on the de nsity, dynamic modulus of elasticity, compressive, tensile and flexural strength were studied experimentally. It was found that the strength of no-fines concrete is lower that that of normal weight concrete, but sufficient enough for structural use. Due to its high ratio of continuous voids, this concrete has high water permeability. The suggested mixtures can be used for cast in-situ walls in low-rise, low cost housing (later plastered externally to reduce air and water permeability).

Discrete element modelling of mechanical behaviour of pervious concrete

Abstract: This study proposes an alternative numerical strategy that combines different DEM models to simulate the compaction process and predict the mechanical performance of pervious concrete. An experimental program was performed to assess the compressive and tensile behaviours of pervious concrete mixes with 3 aggregate-to-paste content subjected to 3° of compaction. A novel constitutive law was proposed to simulate the particle-particle mechanical interaction at a meso-structural level. Results show that this simulation strategy is capable of predicting the experimental compressive and tensile performances while capturing the fracture pattern observed in the experimental program. This opens up the possibility of performing a numerical parametric design of mix composition and production processes before undertaking experimental verifications, which might reduce the number of tests needed to achieve the composition that better suits the mechanical requirements of each application.