Abstract: A plastic gel grouting material, which comprises a silica type non-hardening powdery material and water or a silica type non-hardening powdery material, a calcium type hardening developing material and water as active ingredients, is statically pressure-injected into a soft, loose or weak ground to thereby form masses derived from the grouting material per se in the ground, and concurrently therewith, to compact the surrounding earth and sand, thereby increasing density of the ground. A plastic gel grouting material is provided which loses its flowability with time or by dewatering to form masses derived from the grouting material per se in a ground and which comprises a silica type non-hardening powdery material and water or a silica type non-hardening powdery material, a calcium type hardening developing material and water as active ingredients.

Abstract: A plastic gel grouting material, which comprises a silica type non-hardening powdery material and water or a silica type non-hardening powdery material, a calcium type hardening developing material and water as active ingredients, is statically pressure-injected into a soft, loose or weak ground to thereby form masses derived from the grouting material per se in the ground, and concurrently therewith, to compact the surrounding earth and sand, thereby increasing density of the ground. A plastic gel grouting material is provided which loses its flowability with time or by dewatering to form masses derived from the grouting material per se in a ground and which comprises a silica type non-hardening powdery material and water or a silica type non-hardening powdery material, a calcium type hardening developing material and water as active ingredients.

Abstract: A common feature of the method and apparatus for multipoint grouting resides in using a multiple injection apparatus having a plurality of unit pumps in one plant, driven independently of each other and controlled by a centralized control device. The plurality of the unit pumps are connected through ducts to a plurality of injection pipes each having an outlet, inserted in a plurality of injection points in ground. By operations of the plurality of the unit pumps, ground improving material is injected from the plurality of the outlets into the plurality of the injection points in the ground.

Abstract: When an improving material used for ground improving construction is ejected into the ground, an improving material having a predetermined gel time is ejected through a vast number of points simultaneously or selectively from ejection ports provided in improving material transport passages such that the positions of the ejection ports are offset. The improving material can be ejected through the vast number of points as designed. A stroke, start and stop of an advancing and retreating movement adjusting device can be adjusted through a screw of the advancing and retreating movement adjusting device. A slide guide as a supporting mechanism is fitted to a slide bar so that even if a load deviated with respect to a piston rod is applied. The piston can be advanced and retreated smoothly, and an automatic on-off valve is interposed in the piston so that the improving material can be intaken and discharged smoothly.

Abstract: When an improving material used for ground improving construction is ejected into the ground, an improving material having a predetermined gel time is ejected through a vast number of points simultaneously or selectively from ejection ports provided in improving material transport passages such that the positions of the ejection ports are offset. The improving material can be ejected through the vast number of points as designed. A stroke, start and stop of an advancing and retreating movement adjusting device can be adjusted through a screw of the advancing and retreating movement adjusting device. A slide guide as a supporting mechanism is fitted to a slide bar so that even if a load deviated with respect to a piston rod is applied. The piston can be advanced and retreated smoothly, and an automatic on-off valve is interposed in the piston so that the improving material can be intaken and discharged smoothly.

Abstract: A suspension-type grouting liquid for injection into a ground includes sodium aluminate having a mol ratio of 10 or more; and slag, wherein the mol ratio of sodium aluminate is defined as molar concentration of Na.sub.2 O/molar concentration of Al.sub.2 O.sub.3. Preferably, the slag is fine grained and has a specific surface area of 8000 cm.sup.2 /g or more. The grouting liquid may further include at least one additional material selected from the group consisting of cement and dispersant. Preferably the cement is fine grained and has a specific surface area of 8000 cm.sup.2 /g or more. The grouting liquid shows high strength of consolidation in use in spite of having a low viscosity and a long gelation time, and shows a long duration of the strength of consolidation. Another embodiment of the grouting liquid includes water glass having a mol ratio of 2.5 or less; and slag, wherein the mol ratio of the water glass is defined as molar concentration of SiO.sub.2 /molar concentration of Na.sub.

Abstract: A revetment comprised of nesting, interlocking, building blocks and means to adjust each block between backfilling operations. Identical T-shaped building blocks nest vertically and horizontally, and locking pins which interlock the opposite sides of the T-caps of the blocks hold the blocks in place. Channel-shaped brackets are secured to the back faces of the blocks and adjustable anchor members are secured to the channel-shaped brackets. Adjusting the length of each anchor member alters inclination to the vertical of each block as required. After proper alignment of the blocks by anchor member adjustment, the anchor members are embedded and secured in place by backfill, which is then compacted, such as by rolling or by other state-of-the-art means.

Abstract: A revetment formed from orthogonally arrayed reinforcing rods secured together. A membrane is secured to the back side of the reinforcing rods to retain backfill compacted behind the revetment, or a vegetation ground cover may be planted on the exposed surface of the revetment to prevent erosion. Horizontal anchor rods secured to the revetment rods extend rearwardly therefrom and are embedded in the backfill to stabilize the revetment. Adjustable anchor rods allow tension to be selectively applied to the revetment for the purpose of alignment.

Abstract: A suspension-type grouting liquid for injection into a ground having excellent penetration properties, e.g. low viscosity and long gelation time, and having comparatively high strength after consolidation. The suspension-type grouting liquid for injection into a ground consists essentially of slag, or a combination of slag and cement, alkali metal aluminates, and water. The slag is a fine grain having specific surface area of 5000 cm.sup.2 /g or more, and the alkali metal aluminates have a mole ratio of ({Me.sub.2 O}/{Al.sub.2 O.sub.3 }) of 2.8 or more, in which Me means alkali metal, {Me.sub.2 } and {Al.sub.2 O.sub.3 } represent, respectively, molar concentration of Me.sub.2, and Al.sub.2 O.sub.3.

Abstract: A ground impregnation process which is disclosed herein comprises injecting an alkaline ground impregnating material, with carbon dioxide gas passed through blowing nozzles joining said impregnating material, into a ground. In this process, the pressure of carbon dioxide and the opening size of the blowing nozzle are determined to provide a constant amount of carbon dioxide gas blown, irrespective of a variation in ground pressure. In this manner, the carbon dioxide gas joins the alkaline ground impregnating material at a given ratio.

Abstract: A system for preparing a ground impregnating material which comprises a line for feeding a base liquid component of the ground impregnating material, such as an aqueous sodium silicate solution, and a high pressure carbon dioxide gas bomb connected via a carbon dioxide gas delivery line to the base liquid component feed line. The carbon dioxide gas delivery line has a carbon dioxide blowing nozzle provided therein. The carbon dioxide gas blowing nozzle comprises a disk centrally perforated with a nozzle bore. A plurality of the carbon dioxide gas blowing nozzles having different opening diameters may be switchably provided in parallel in the carbon dioxide gas delivery line.

Abstract: An injection process for solidifying a soft ground by injecting a blend of water glass type grout thereinto which is a non-alkaline aqueous solution of silicic acid obtained by the mixing water glass into an aqueous solution of acidic reactant so as to remove alkali from the water glass, and an injection apparatus for practicing the injection process which comprises a mixing container for preparing the non-alkaline aqueous solution of silicic acid by adding and mixing the water glass into the aqueous solution of acidic reactant.

Abstract: An injection process for solidifying a soft ground by injecting a blend of water glass type grout thereinto which is a non-alkaline aqueous solution of silicic acid obtained by the mixing water glass into an aqueous solution of acidic reactant so as to remove alkali from the water glass, and an injection apparatus for practicing the injection process which comprises a mixing container for preparing the non-alkaline aqueous solution of silicic acid by adding and mixing the water glass into the aqueous solution of acidic reactant.

Abstract: A method for constructing a soil structure comprising a step of disposing reinforcements into a ground to thereby unify the soil structure by the friction force caused between the reinforcements and soil particles, said reinforcements being principally of rigid structure which possess a property of flexibility at the time of at least the disposition of said reinforcements to accommodate the same to any displacements of soil, the friction force being caused between said rigid structures and said soil particles, to thereby unify the soil structure.

Abstract: In a method of consolidating soils by injecting a hardner thereinto, a mixture of an aqueous solution of water glass and acidic reactant is employed as the hardener, the aqueous solution being prepared to be within the range of from weak acidity to weak alkalinity in pH value, to prevent the occurrence of pollution such as soil pollution or subterranean water polutions.

Abstract: A method of consolidating a poor quality soil or a water leaking soil by injecting hardeners thereinto, in which a mixture of water and gelling agent and a water glass aqueous solution containing gelling agent are employed as said hardeners, said hardeners are joined together and injected into said soil, whereby to modify the soil into a uniformly and strongly consolidated soil or water-tight soil.