Showing papers on "Pervious concrete published in 1988"

Block-stacked retaining wall for revetment of river and its construction

Abstract: PURPOSE:To permit the use of river-bed water under the ground by using water- permeable concrete blocks for the portion lower than the riverbed of a concrete block-stacked retaining wall. CONSTITUTION:Usual water-impermeable concrete blocks 3 are used for the lowest stage blocks in contact with the upside of a foundation concrete 7. Water-permeable porous concrete blocks 2 are also used for a part or all of blocks lower than the riverbed and its neighbor, and usual concrete blocks 3 are used for the portion high than the riverbed to construct a retaining wall 1. Since river-bed water under the ground from river passes through the blocks 2, the river-bed water can be used as a resource for agricultural and city waters.

Mfg. process of porous concrete with light skeleton materials

Abstract: The principle feature of this invention consists in the use of natural fluorite as gas carrier to bring air or other gases into the slurry, making the volume of slurry expand, and to make the concrete of gas carrier porous on hardening. If light skeleton materials are used, then the porous concrete with light skeleton materials will be obtained. Becuse the fine skeleton materials in the concrete is replaced by gas bubble, the powdered coal ash is used as cementing material and the artificial or natural light skeleton material or industrial waste residue is used as skeleton materials in this invention, such concrete has adventages of high strength, low shrinkage and saving cement, etc,.

OPC and modified GGBFS concretes cured in hot climates

Abstract: Problems are frequently encountered in producing good quality concrete in hot climates. Inadequate curing results in early cracking or porous/permeable concrete or both which leads to deterioration (including reinforcement corrosion) of structures. This research investigated the effect of curing on the performance of OPC and GGBFS concretes in a hot climate. Five curing methods were selected and applied to each concrete mix. The methods used representing the range of practical methods available on site. Moreover. the effect of cement replacement materials on concrete durability was studied. Ground granulated blast-furnace—similar to that produced in Algeria—was used in three different percentages, namely 30%, 50% and 70%. Finally the performance of specimen sizes was also investigated. Cubes and beams specimens have been compared to walls specimens of reasonable size to represent full size structural members. [Continues.]

Porous lightweight concrete

Abstract: The invention relates to a porous lightweight concrete for producing floors, slabs and similar mouldings with defined components of mineral fillers such as sand, inorganic binders such as cement and lime, aluminium powder as blowing agent and water. In this arrangement, in order to make possible an adaptation of the properties of the gas concrete to, inter alia, particular climatic conditions and to achieve the simplest possible production, it is proposed by the invention that the raw material which is mixed so as to be pourable now contains the following components: a) the initially dry-mixed filler and binder with the addition of water and finally blowing agent or b) mineral filler ground with water to form slurry with subsequent mixing with binder and further water and finally blowing agent. Thus, with a minimum number of conventional components used, a porous concrete is produced whose bulk density is 400-600 kg/m and whose physical properties, in particular as regards thermal insulation and compressive strength, meet the requirements in the construction industry. Some preferred formulations are also proposed by the invention.