Strong porous concrete for underwater constructions - withstanding press. of underground waters and erosion by waves

摘要

Materials for underwater constructions, contg. fillers such as cement, gravel or the like and a binder such as cement, or cement-lime are improved in that the filler particles show irregular size distribution so that pores are formed in the resulting concrete rendering it water-permeable. The compsn. pref. contains 0.05-30.00 wt. % (w.r.t. the water) of a polymeric addition, pref. a cellulose ether, polyacrylamide or polyethylene oxide. Alternatively it may contain 0.08-2.5 wt. % (w.r.t. the water) of an alginate or casein. This water-permeable concrete is suitable for underwater constructions exposed to pressure of underground waters such as walled canals, coast strengthening constructions, wells. etc. Water penetrated into the concrete and the pressure is relieved. The addition of polymers improves the strength of the concrete, esp in early stages so that it can be moulded in situ under water, it also improves the erosion resistance, esp. in sailing canals and coastal structures. The water retention capability is increased.