51results about How to "Reduce temperature cracks" patented technology

The invention provides a temperature-control cooling system for a large-size concrete structure and a cooling control method of the temperature-control cooling system, and relates to the technical field of large-size concrete construction by aiming at the problems that in the existing method, the arrangement blindness of cooling pipes is great, the inside temperature distribution rule of the concrete cannot be well combined, and the inside temperature reduction uniformity of the cooling pipes cannot be effectively controlled. Cooling water pipe units are horizontally arranged in a template, and comprise two cooling water pipe groups, the two cooling water pipe groups are staggered and overlapped, the cooling water pipes of the two cooling water pipe groups are parallel and are separately arranged, and the flowing directions of cooling circulation water in the adjacent cooling water pipes are opposite. The method comprises the following steps that 1, a finite element model is created, and in addition, the water thermalization analysis is carried out for judging the highest temperature difference and the temperature gradient; 2, the arrangement scheme of the cooling water pipe units is primarily determined; 3, the information of the arrangement scheme is substituted into the finite element model for analogue simulation, when the judging result is assertive, the construction is carried out according to the arrangement scheme, and when the judging result is negative, the arrangement and the flow rate of the cooling water pipe units are regulated until the requirements are met.

The invention discloses C70 mass concrete. The C70 mass concrete is prepared from the following components by mass: 140 to 170 parts of water, 400 to 450 parts of cement, 1,000 to 1,200 parts of crushed stone, 550 to 650 parts of gravel, 70 to 110 parts of coal ash, 60 to 90 parts of mineral powder, 30 to 70 parts of silica fume, 8 to 10 parts of a pumping agent, 35 to 45 parts of an anti-crackingagent, and 0.3 to 0.4 part of an internal curing agent. The invention also discloses a preparation method for the C70 mass concrete. The method comprises a first step of uniformly mixing sand, graveland water and a second step of adding other components and carrying out uniform mixing under stirring. According to the composition of the mass concrete in the invention, mineral powder, silica fumeand fly ash are used as mineral admixtures and can delay the release rate of cement hydration heat and reduce the shrinkage and deformation of the concrete, and the mineral admixtures acts synergistically with the other components to inhibit the generation of cracks at the same time; and the preparation method of the invention is simple in process and easy to implement.

The invention discloses a method for preparing a carbon-fixation filling paste from waste concrete. The method comprises the following steps: industrial waste gas is dedusted, and then is mixed with normal temperature air, a waste concrete and a gangue mixture is crushed in the obtained industrial exhaust gas atmosphere, and coarse aggregates, fine aggregates and fine powder obtained after screening and carbon dioxide in the industrial exhaust gas undergo a carbonization reaction in a carbon fixation chamber; and the carbon-fixation coarse aggregates, the carbon-fixation fine aggregates, a filling paste additive, cement, phase change material microcapsules and water are stirred and mixed to form a filling body mixture, and the industrial exhaust gas is continuously injected in the stirring, mixing and conveying process of the filling paste to make the filling paste and the carbon dioxide in the industrial exhaust gas undergo the carbonization reaction in order to obtain the carbon-fixation filling paste. The carbonization reaction of the waste concrete and carbon dioxide is fully used, so the damages of the waste concrete to the environment are reduced, and the emission of greenhouse gases is reduced; and hydration heat is fully used in the carbonization reaction, so the filling effect of the carbon-fixation filling paste is good.

The invention discloses a recycled concrete, which is characterized in that the recycled concrete is prepared from the following components by weight: 60~95 parts of water, 40~64 parts of cement, 38~62 parts of ore powder, 22~34 parts of fly ash, 280~350 parts of natural sand, 210~260 parts of recycled coarse aggregate, 70~120 parts of recycled fine aggregate, 6~8 parts of silicon powder, and 1~2parts of modified polyacrylic acid high-efficiency water reducing agent. In conclusion, the recycled concrete has the advantages of improving the compressive property of concrete and improving the rheological property, mechanical property, volume stability and durability of concrete.

The light energy-saving heat insulating wall material is produced with light aggregate in 1.2-2.6 wt%, gelating material in 72-76 wt% and sand in 22-26 wt%, as well as water in 35-88 wt% of gelating material, bulking agent in 13 wt% of gelating material and water reducing agent in 1 wt% of gelating material. The light energy-saving heat insulating wall material has the advantages of saving in land, low power consumption, light weight, easy construction, high heat insulating performance, etc. and may be used in network structure building system and non-bearing wall building system.

The invention relates to a detachable gravity dam and a construction and dismounting method thereof, and belongs to the technical field of water conservancy projects. The detachable gravity dam comprises a drainage grouting gallery, an anti-seepage curtain, a dam foundation drainage hole, a middle pier, a side pier and a transverse seam, and further comprises an upstream concrete panel, building block concrete, a downstream concrete panel, a plain concrete cushion layer and a dam foundation anchor bar; the building block concrete is formed by connecting prefabricated building blocks through bolts according to a certain sequence; the upstream concrete panel and the downstream concrete panel are correspondingly poured on the upper surface and the downstream side of a dam body, and the plainconcrete cushion layer is laid on the dam foundation, the detachable building block concrete is built on the plain concrete cushion layer, and the dam foundation anchor bar is arranged in each hoisting hole of the bottom-layer building block concrete. According to the detachable gravity dam and the construction and dismounting method thereof, the advantages of reliable quality and high construction efficiency of a prefabricated concrete component can be fully utilized, so that temperature cracks in the dam body are reduced, the safety of the gravity dam is ensured, meanwhile, the dam body is convenient to detach, and the economical and environment-friendly effects are realized.

The invention discloses an anti-seam temperature control pouring method and structure for foundation mat mass concrete. The method is characterized by comprising the following steps that a water through cooling device is arranged in a space to be poured of mat concrete, and cooling water is used for water through cooling; concrete is poured into the space to be poured; a heat-storage humidity-preservation heat-preservation measure is adopted for the surface of the mat concrete finishing pouring; and die removal is carried out on the mat concrete.

The invention discloses buried water supply steel pipe liner mortar and belongs to the technical field of polymer cement mortar. According to the buried water supply steel pipe liner mortar provided by the invention, raw materials comprise a gel material, fine aggregate, calcium triple superphosphate, hydroxyethyl cellulose ether, a water reducing agent, dispersible adhesive powder, a de-foaming agent, an expanding agent and basalt fibers, wherein the water-material ratio of the mortar is 0.3 to 0.4, the 28d strength of the mortar is 40 to 60MPa, the breaking strength is 10MPa or more, the bonding strength is greater than 1.0MPa and the shrinkage rate is -0.2 to +0.05 percent. The mortar disclosed by the invention has micro-expansion and flexible properties so that the mortar has an adhesion force on a steel pipe and can bear stress generated by the deformation of the steel pipe under high-pressure water flow.

The invention discloses a treatment method of assembled-type prefabricated component wallboard joints. When being used for treating vertical splicing joints and top horizontal plate joints among prefabricated components, the treatment method includes following steps: S1, cleaning the joints; S2, preparing anti-cracking mortar; S3, filling with the anti-cracking mortar; S4, filling with epoxy resin glue; S5, sealing. When being used for treating connecting joints formed by connecting the prefabricated components with a cast-in-place wall, the treatment method includes following steps: S1, expanding the joints; S2, filling with epoxy resin glue; S3, sealing. The treatment method has the advantages of simple process, easiness in operation and high economic value.

The invention discloses activate micro powder prepared through wind quenching method steel slag and directly-discharged pulverized fuel ash and a method. A raw material comprises 60 to 70% of steel slag, 20 to 30% of pulverized fuel ash, 16 to 20% of lime mixture and 0.1 to 0.3% of polycarboxylate superplasticizer powder by mass percent, the raw material is added into a weightless mixing stirrer,stirring is carried out to enable the material to be sufficiently mixed to be uniform, through a wind quenching method, the amorphous mineral phase on the surface of the steel slag is obviously increased, potential activity is increased, through a grinding aid, reinforced fibers, the polycarboxylate superplasticizer powder and monox, the activity is higher, compatibility with cement is good, the pulverized fuel ash delays the hydration speed, the temperature rise caused by heat transmission by water of the concrete can be reduced, temperature cracks generated by the concrete can be prevented,binding force of the concrete can be obviously improved, durability is improved, and for solving the problem that the grinding effect is affected due to the inconsistent steel slag sizes, and a screening auxiliary device for smashing of the steel slag is specially made

The invention discloses a preparation method for baseboard of main pipe and sluice and step-style construction joint for side wall of flow channel layer. Under the circumstance that the flow channel layer is the special-shaped structure of gradient section and with the adoption of floor pouring technique, the height of the side wall of flow channel layer within two thirds of the width of the outboard of side wall is about 0.5m. The improved section of the side wall of flow channel layer is segmented by adopting overhanging model. By means of welding, a sealing plate is connected with a reticulate frame. After the floor pouring process is finished, the formed faulting is used as the stress release channel for the side wall of flow channel layer. The preparation method for baseboard of mainpipe and sluice and step-style construction joint for side wall of flow channel layer can reduce the difficulty in constructing baseboard, enlarge the pouring space of concrete base slab and improve the managing and controlling level and quality of the floor pouring of concrete base slab. The preparation method for baseboard of main pipe and sluice and step-style construction joint for side wall of flow channel layer can use the formed faulting in the floor pouring section as the release channel for the side wall of flow channel layer to reduce the restriction of the baseboard on the flow channel layer, which is beneficial to control the cracks caused by the temperature of concrete on the side wall of flow channel layer. The sealing plate, together with the floor pouring section, has a good water proofing effect. In one word, the preparation method for baseboard of main pipe and sluice and step-style construction joint for side wall of flow channel layer can obviously save the time forconstruction and accelerate the process of construction.

The invention discloses an impact-resistant nanometer boron nitride-modified reactive powder concrete. Raw materials of the impact-resistant nanometer boron nitride-modified reactive powder concrete include cement, nanometer boron nitride, silica fume, fly ash, sands, a water reducer and water. The nanometer boron nitride can significantly enhance the dynamic compressive strength, dynamic peak strain and impact toughness of the reactive powder concrete. When the strain rate is in a range of 200-800/s and the dosage of the nanometer boron nitride is 0.25-0.5%, the dynamic compressive strength of concrete can be increased by 83.8%, the dynamic peak strain can be increased by 30.5%, and the impact toughness can be increased by 94.6%.

The invention discloses a magnesium high-performance anti-cracking agent for concrete as well as a preparation method and application thereof. The magnesium high-performance anti-cracking agent is prepared from the following raw materials of: 50 to 63 weight percent of light calcined magnesia clinker, 21 to 34 weight percent of phosphorus slag, 5 to 10 weight percent of coal slag, 1 to 3 weight percent of quartz sand, 1 to 2 weight percent of early strength agent and 0.5 to 1.3 weight percent of novel hydration heat absorbent. The light calcined magnesia clinker is formed by calcining magnesite, an iron material and bauxite at high temperature. The preparation method of the novel hydration heat absorbent comprises the following steps of: mixing maleic anhydride and sodium thiocyanate in a molar ratio of (7-9): 1; adding water to form a solution; dropwise adding a sodium benzenesulfonate solution in a nitrogen atmosphere; heating to 55-65 DEG C, carrying out heat preservation reaction for 2 hours; and cooling and drying to obtain the novel hydration heat absorbent. The anti-cracking agent disclosed by the invention has the functions of compensating concrete shrinkage, enhancing the mechanical property of concrete and absorbing cement hydration heat, and fundamentally improves the anti-cracking performance of the concrete material.

According to the double-doped biomass ash concrete and the manufacturing method thereof, industrial waste fly ash and CMA are doped in the concrete to replace part of cement, heat released by hydration heat of the fly ash is little, hydration heat reaction is reduced, temperature cracks are reduced, the CMA can reduce the heat conductivity coefficient of a base material, the self-heat-preservation function is achieved, and the strength meets the requirement; and the double-doped biomass ash concrete is low in cost, green and environment-friendly, can be applied to concrete with various requirements due to the specific performance, and improves the performance of the concrete.