Summary of the invention
In order to solve the problem, the present invention is by having carried out effective analysis to the soil of Along The East Coast of Zhejiang And Jiangsu Provinces, develop a kind of not only economy but also the soil-solidified-agent being applicable to saline soil of environmental protection, adopt physical-chemical reaction, improve the physico-mechanical properties of soil, certain ultimate compression strength should be reached, the corrosion of resistance to salt again, and make its water stability excellent, a difficult problem for the cleaning of soil mud and ground hardening can be solved, to meet civil engineering construction that is coastal and supersalinity saline soil place.
The object of the present invention is to provide a kind of solidifying agent for salt marsh mud soil hardening.
Another object of the present invention is to the application that a kind of solidifying agent for salt marsh mud soil hardening is provided.
The technical solution used in the present invention is:
For a solidifying agent for salt marsh mud soil hardening, it is made up of the raw material of following mass fraction:
High-alumina cement 0.8 ~ 1.2 part,
0.3 ~ 0.4 part, calcium carbonate,
Talcum powder 0.2 ~ 0.3 part,
Water reducer 0.1 ~ 0.2 part,
6 ~ 7 parts, lime,
Sulfur-containing mixture 0.2 ~ 0.3 part;
Beta-naphthalenesulfonic-acid formaldehyde sodium salt condenses 0 ~ 0.1 part.
Further, above-mentioned lime is selected from as calcium lime powder.
Further, above-mentioned sulfur-containing mixture is the mixture of sulfurated lime, calcium sulfate and magnesium sulfate.
A method for salt marsh mud soil hardening treatment, is characterized in that: comprise the following steps:
1) by above-mentioned solidifying agent and saline soil mixing, the mass ratio of solidifying agent and saline soil is 1:(10 ~ 15), adjustment water consumption is 10 ~ 20% to the water ratio of compound;
2) make 1) in solidifying agent and saline soil fully react 8 ~ 10h;
3) by 2) in abundant reacted mixture, compaction moulding, compaction reaches the maximum dry density of this mixing with soil material, places 7 ~ 28 days.
The invention has the beneficial effects as follows:
1) in the experiment of saline soil being solidified at solidifying agent of the present invention, within 7 days, unconfined compression strength reaches 4.8MPa, 5.1MPa, 7.9MPa, standard bottom line 3.2MPa during super design far away, as long as and maintenance is proper, the space of its strength enhancing will be very large, can 9 ~ 10MPa be reached, meanwhile, not affect its corrodibility of anti-salt and the solvability of water resistant; Therefore, in water stabilizing, corrosion resistance and resistance to high-intensity performance, this solidifying agent all shows its uniqueness and superiority, and under same condition, its reference is much higher than the most of soils solidifying agent on high-alumina cement and market.
2) solidifying agent of the present invention, could successful curing supersalinity saline soil mud, solves a sclerosis difficult problem for salt pan, saltern, seabeach high content of salt mud soil! There is good practicality and promotion prospect; Meanwhile, a difficult problem for mud discharge, outward transport is also solved; Floor space and the pollution to environment can also be reduced, be conducive to environmental protection; Also reduce capital construction cost etc.; There is very large economic benefit and social benefit, mud modification hardening treatment on the spot, belong to recycling economy and utilize, also belong to environmental protection and economy category, its remarkable in economical benefits.
3) solidifying agent chemical composition of the present invention is easy to get, production technique is simple, less demanding to equipment use, therefore total cost reduces greatly, further, it has the features such as early strength is high, later strength development potentiality is large, adjustability good, easy construction, with strong points, excellent durability, posterior settlement are little.
4) solidifying agent of the present invention can also utilize industrial sulfur-bearing waste residue, there is not environmental pollution in production process and application process, without violent luminous exothermic phenomenon, without radiation, dust hazard, identical with cement treated method, there is the meaning of environmental protection, synchronous with the strategy of sustainable development.
Embodiment
for the preparation method of the solidifying agent of salt marsh mud soil hardening, comprise the following steps:
Each raw material is taken respectively: high-alumina cement 0.8 ~ 1.2 part by following mass fraction, 0.3 ~ 0.4 part, calcium carbonate, talcum powder 0.2 ~ 0.3 part, water reducer 0.1 ~ 0.2 part, 6 ~ 7 parts, lime, sulfur-containing mixture 0.2 ~ 0.3 part, beta-naphthalenesulfonic-acid formaldehyde sodium salt condenses 0 ~ 0.1 part, by the above-mentioned raw materials mixing weighed up, the solidifying agent for salt marsh mud soil hardening can be obtained.
Above-mentioned sulfur-containing mixture is preferably the mixture of sulfurated lime, calcium sulfate and magnesium sulfate.
Above-mentioned lime is preferably calcium lime powder.
the method of salt marsh mud soil hardening treatment, comprises the following steps:
1) above-mentioned solidifying agent and saline soil are mixed, the mass ratio of solidifying agent and saline soil is 1:(10 ~ 15), adjustment water consumption is 10 ~ 20% to the water ratio of compound;
2) make 1) in solidifying agent and saline soil fully react 8 ~ 10h;
3) take out 2) in abundant reacted mixture, compaction moulding, compaction reaches the maximum dry density of this mixing with soil material, places 7 ~ 28 days.
the present invention is used for the curing mechanism of the solidifying agent of salt marsh mud soil hardening
The present invention adopts the combined soil solidifying agent of the inorganic materials compositions such as unslaked lime, high-alumina cement, talcum powder, its curing mechanism mainly contains two large classes, i.e. filling effect and alkali carbonate effect, the structural formation formed is cementing properties hydrate, the mainly fill gaps wherein played a decisive role and gelling material.
After high-alumina cement is water-soluble, by with calcium oxide hydration after the Ca (OH) that generates
2and CaCO
3reaction generates C-S-H class material, and this provides certain early strength by for curing soil; Taking talcum powder as basic raw material, by carrying out Mechanochemical Activation to carbonatite powder, realizing the SiO of inertia carbonate and dissolved state under alkali-activated carbonatite condition
2water generation reaction closes the reaction of Calucium Silicate powder (magnesium) gel at normal temperatures, and it forms the hydrated magnesium silicate of mainly serpentine type and calcium silicate hydrate (magnesium) gel of gyrolite type; In addition, the Silica hydrogel of some amount is also had in reaction product, secondly, cured granulate and soil particle are filled mutually, form packed structures closely, and overlap with calcium silicate hydrate (magnesium) gel that generates in reaction, play strong skeletal support effect, enhance the bulk strength of solidified earth system, and the lasting generation of chemical reaction will make solidified earth system more tight, intensity time and increasing progressively.
Main chemical reactions in solidifying agent:
1)CaO+H
2O→Ca(OH)
2
2)Ca(OH)
2+nH
2O→Ca(OH)
2·nH
2O
3)xCa(OH)
2+xMgO·ySiO
2+mH
2O→ CaO(MgO)x·(SiO
2)y·(m+x)H
2O
4)Ca(OH)
2+MgSiO
3→Mg(OH)
2+CaSiO
3
5)CaSO
4+mH
2O→CaSO
4·mH
2O
Reaction mainly passes through OH
-ion pair MgSiO
3lattice destroys, and makes Ca
2+ion and Mg
2+ion release, but follow-up reaction and Alkali-carbonate reaction are different.Owing to there is the silicate anion of a large amount of various state in liquid phase, therefore dissolve the Ca
2+ion and Mg
2+ion reacts with it soon, and generate water and Calucium Silicate powder and hydrated magnesium silicate, wherein hydrated calcium sulfate mainly plays the effect of filling pore.
The main effect model of this solidifying agent:
1) by the reaction of unslaked lime and water, provide hydroxide ion, produce a stronger alkaline environment, improve the speed of reaction, accelerate the generation of gum material.
2) inherently a large amount of acid ions is contained in soil, they and Ca
2+, Mg
2+reaction, by continuation generate other gum material.
3) solidified earth is closely filled by hydrated calcium sulfate, calcium carbonate, adds intensity.
Below in conjunction with specific embodiment, the present invention is further illustrated, but be not limited thereto.
embodiment 1:for the preparation method of the solidifying agent of salt marsh mud soil hardening
Each raw material is taken respectively: high-alumina cement 1 part by following mass fraction, 0.34 part, calcium carbonate, talcum powder 0.28 part, water reducer 0.18 part, calcium lime powder 6.8 parts, sulfur-containing mixture (mixture of sulfurated lime, calcium sulfate and magnesium sulfate) 0.24 part, beta-naphthalenesulfonic-acid formaldehyde sodium salt condenses 0.1 part, by the above-mentioned raw materials mixing weighed up, the solidifying agent for salt marsh mud soil hardening can be obtained.
embodiment 2:for the preparation method of the solidifying agent of salt marsh mud soil hardening
Each raw material is taken respectively: high-alumina cement 1 part by following mass fraction, 0.34 part, calcium carbonate, talcum powder 0.28 part, water reducer 0.16 part, calcium lime powder 6.2 parts, sulfur-containing mixture (mixture of sulfurated lime, calcium sulfate and magnesium sulfate) 0.28 part, beta-naphthalenesulfonic-acid formaldehyde sodium salt condenses 0.1 part, by the above-mentioned raw materials mixing weighed up, the solidifying agent for salt marsh mud soil hardening can be obtained.
embodiment 3:for the preparation method of the solidifying agent of salt marsh mud soil hardening
Each raw material is taken respectively: high-alumina cement 1 part by following mass fraction, 0.34 part, calcium carbonate, talcum powder 0.28 part, water reducer 0.16 part, calcium lime powder 6.2 parts, sulfur-containing mixture (mixture of sulfurated lime, calcium sulfate and magnesium sulfate) 0.28 part, beta-naphthalenesulfonic-acid formaldehyde sodium salt condenses 0.05 part, by the above-mentioned raw materials mixing weighed up, the solidifying agent for salt marsh mud soil hardening can be obtained.
embodiment 4:for the preparation method of the solidifying agent of salt marsh mud soil hardening
Each raw material is taken respectively: high-alumina cement 0.8 part by following mass fraction, 0.3 part, calcium carbonate, talcum powder 0.2 part, water reducer 0.1 part, calcium lime powder 6 parts, sulfur-containing mixture (mixture of sulfurated lime, calcium sulfate and magnesium sulfate) 0.2 part, by the above-mentioned raw materials mixing weighed up, can obtain the solidifying agent for salt marsh mud soil hardening.
embodiment 5:for the preparation method of the solidifying agent of salt marsh mud soil hardening
Each raw material is taken respectively: high-alumina cement 1.2 parts by following mass fraction, 0.4 part, calcium carbonate, talcum powder 0.3 part, water reducer 0.2 part, calcium lime powder 7 parts, sulfur-containing mixture (mixture of sulfurated lime, calcium sulfate and magnesium sulfate) 0.2 part, by the above-mentioned raw materials mixing weighed up, can obtain the solidifying agent for salt marsh mud soil hardening.
embodiment 6:the method of salt marsh mud soil hardening treatment
With Xu Xu new district, Lianyun Harbour saline soil for handling object, it has following characteristics:
1, this area's type of salinized soil is typical chlorine saline soil, ρ (Cl
-)/ρ (SO
4 2-) mean value is between 10 ~ 20, maximum can reach 58;
2, present obvious salinity downtrending within the scope of from earth's surface to 15m, soil type is successively from over-salted soil-strong saline soil-medium salting soil; Corresponding lyotropic salt point mass concentration, corrosive characteristics also present the decline trend from earth's surface to 15m depth range, show the impact of saltern for a long time on this area;
3, soil is micro--weak corrosion to concrete corrodibility, and corrosion class is more weak; Cl in soil
-especially within the scope of near surface 15m, mass concentration is higher, shows the strong corrosion effect to reinforcing bar, pipeline;
4, the lyotropic salt mass concentration feature of water body and soil similar, in underground water, villaumite mass concentration is high, display aggressive, and the influence on groundwater that the high salinity also illustrating in soil is subject to coastal waters water is larger.
Treatment process is:
1) solidifying agent prepared of Example 1 and Xu Xu new district, above-mentioned Lianyun Harbour saline soil mix, and the mass ratio of solidifying agent and saline soil is 1:10, and adjusting water consumption to the water ratio of mixing with soil material is 15%;
2) by 1) in mixture plastic bag sealing and in plastics bag, add 5 ~ 10mL water make solidifying agent and soil fully react 8 ~ 10h;
3) take out 2) in abundant reacted mixture, compaction moulding, compaction reaches the maximum dry density of mixing with soil material, rest 1 day with plastic bag sealing again, again by sunlight photograph solarization 6 days naturally, then measure its various performance, wherein unconfined compression strength be 4.8MPa(as shown in Figure 1).
The method is for Lianyungang of Jiangsu Xu Xu open area PCK steel pipe road and the interim sidewalk of on-site.
embodiment 7:the method of salt marsh mud soil hardening treatment
1) solidifying agent prepared of Example 2 and Xu Xu new district, Lianyun Harbour saline soil mix, and the mass ratio of solidifying agent and saline soil is 1:15, and adjusting water consumption to the water ratio of mixing with soil material is 20%;
2) by 1) in mixture plastic bag sealing and in plastics bag, add 5 ~ 10mL water make solidifying agent and soil fully react 8 ~ 10h;
3) take out 2) in abundant reacted mixture, compaction moulding, compaction reaches the maximum dry density of mixing with soil material, rest 1 day with plastic bag sealing again, naturally solarization 6 days is shone again by sunlight, then measure its various performance, wherein unconfined compression strength is that 5.1 MPa(are illustrated in fig. 2 shown below).
The method is for Lianyungang of Jiangsu Xu Xu open area PCK steel pipe road and on-site goods yard.
embodiment 8:the method of salt marsh mud soil hardening treatment
1) solidifying agent prepared of Example 3 and Xu Xu new district, Lianyun Harbour saline soil mix, and the mass ratio of solidifying agent and saline soil is 1:13, and adjusting water consumption to the optimum moisture content of mixing with soil material is 10%;
2) by 1) in mixture plastic bag sealing and in plastics bag, add 5 ~ 10mL water make solidifying agent and soil fully react 8 ~ 10h;
3) take out 2) in abundant reacted mixture, compaction moulding, compaction reaches the maximum dry density of mixing with soil material, then rests 1 day with plastic bag sealing, then reacts 6 days by immersion-drying cycle repeatedly, then its various performance is measured, its unconfined compression strength is 7.9MPa, and is insoluble to salt solution, soaks also corrosion-free phenomenon and occur in salt solution, through practice, repeatedly soak-dry the saline soil ultimate compression strength after making solidifying agent process is significantly raised.
The method is for Lianyungang of Jiangsu Xu Xu open area PCK steel pipe road and on-site goods yard.
embodiment 9:the method of salt marsh mud soil hardening treatment
1) stockyard experiment, bearing pressure is designed to 50 tons/m
2;
2) construction environment requires to avoid rainy season, and natural weather is sunny, and temperature is more high better;
3) first, by engineering machinery, existing place is bulldozed, absolute altitude, mark are carried out in Ge Jiaohe center, place four etc.;
4) unwrapping wire from the central vertical cross of place, each laying width 2.2 ~ 2.6 meters is wide, digs up 400 ~ 500mm, natural air drying, then pulverize by mechanical means with navvy;
5) hardening treatment of the first layer soil: be not less than 250 horsepowers of tractors by below earth more deeply plough dig 350mm, shine dry doubling rotary cultivator under the sun to pulverize, then, the solidifying agent of embodiment 1 preparation is evenly sprinkled into rotary tillage sowing machine, the weight ratio of solidifying agent and dry ground earth is 1:(10 ~ 15), and immediately with plough deeply plough and rotary cultivator carry out mechanical uniform stirring, stir number of times more many more evenly better, spray a small amount of water (making water ratio be 10 ~ 20%) if desired, then, carry out spreading repeatedly with machinery, carry out the steady the first layer of water;
6) hardening treatment of second layer soil: part steps 4) earthen backfill of apoplexy dry grinding enters in ditch, the degree of depth is about 250mm, pulverize the solidifying agent being evenly sprinkled into embodiment 1 and preparing, the weight ratio of solidifying agent and dry ground earth is 1:(10 ~ 15), and immediately with ploughing deeply plough and rotary cultivator carries out mechanical uniform stirring, stirring number of times more many more even better, spraying a small amount of water (making water ratio be 10 ~ 20%) if desired, carry out spreading repeatedly with machinery again, carry out middle layer;
7) hardening treatment of third layer soil: again earthen backfill dark for the about 250mm be left in step 4) is entered in ditch, pulverize the solidifying agent being evenly sprinkled into embodiment 1 and preparing, the weight ratio of solidifying agent and dry ground earth is 1:(10 ~ 15), mix, spray a small amount of water (making water ratio be 10 ~ 20%) if desired and carry out spreading repeatedly with machinery, absolute compacting improves the density of composite soil, carries out third layer water-resisting layer;
8) whole sequence of construction is launched according to vertical " cross weave a mat method ", strengthens the firm stable of whole plate, avoids or the plate fracture that reduces local pressure excessive and cause or fault-layer-phenomenon;
9) hardening treatment of the 4th layer of soil: whole basic hardening treatment is complete, repeatedly integrally carry out spreading with street roller equably, re-lay the thick irregular road of 200mm on surface and pound stone (irregular broken stone 25*25mm), to strengthen surface strength, the mud scum avoiding and reduce surface to cause because of the rainy day and contaminated site;
10) last roll milling forming again, reaches maximum dry density, preserving period be no less than 7 days after can reach goods yard requirement, can normally come into operation, if having particular requirement to weather resistance, preserving period, should not be less than 28 days, if temperature, humidity are too low, then need corresponding prolongation preserving period.