Pile foundation related

I would like to use 1000 kg of ordinary Portland cement per 1 m3, but I would like to know the amount of water used for this purpose.
If the true specific gravity of ordinary Portland cement is 3.16, the capacity of 1000kg is 1000/3.16≒316ℓ, and the remainder is water.
Therefore, 1000ℓ – 316ℓ = 684ℓ.
By the way, the W/C of this cement milk is 68.4%.
There are concerns that the height will remain high due to encountering cobblestones and gravel layers when using the existing pile construction method or driving H steel for earth retaining.
Is there any good solution?
It is wise to add bentonite to the drilling fluid to create a highly viscous bentonite fluid or CB (cement bentonite) fluid that floats the gravel and delays sedimentation.
Recommended products: TB-S , Kunigel GS , Super Clay
I would like to create a high viscosity CB (cement bentonite) liquid.
I am thinking of mixing 60 kg of blast furnace B cement and 10 kg of bentonite per 200 liters of mixing, but how many liters of mixing water (tap water) will be required?
Assuming that the true specific gravity of blast furnace B cement and bentonite is 3.04 and 2.60, respectively, the capacity of blast furnace B cement is 60 kg/3.04≒19.7 liters, the capacity of bentonite is 10 kg/2.60 ≒ 3.8 liters, and the remainder is 176.5 liters of refining water.
Incidentally, the unconfined compressive strength of the CB liquid after hardening is σ28≒1.0N/mm2 .
During drilling using the earth drilling method, the stabilizing liquid in the hole suddenly began to appear to be gelling.
What is the cause, and are there any good solutions?
Rapid deterioration (gelation) of the stabilizing liquid inside the pore is a rare phenomenon, but it has become relatively common these days.
First, the factors that have an adverse effect on the stabilizer can be roughly divided into 1) Ca ions in the cement system and 2) salt (Na ions and Cl ions) contained in seawater.
Considering the latter, whether it is due to the influence of seawater or not, I would guess that the answer is no.
This is because when the stabilizer is affected by seawater, dilution is generally more noticeable than gelation, and the stabilizer becomes diluted.
On the other hand, if soil contaminated with cement is excavated, a rapid gelation reaction will occur.
A common phenomenon these days is that soil that has been backfilled with fluidized soil is often excavated, and sometimes cases of gelation occur.
In such cases, gelation must occur, so it is wise to add the dispersant directly into the pores.
However, there is a risk that the viscosity will drop suddenly, so please be careful to protect points where there is a risk of collapse or skin fall, such as the water layer.
If there is information in advance that the soil is cement-improved soil or fluidized soil replacement soil, adding a gelation inhibitor (dispersant) to the stabilizing solution in advance can reduce or suppress the degree of gelation. will be done.
Since a deep well will be constructed before pile driving, I would like the drilling additive guar gum to be used in preparation.
I would also like to know the amount of the mixture.
Since guar gum is a natural polymer, I will explain on the premise that, strictly speaking, the viscosity of the solution differs from time to time.
It depends on the excavation depth, but if you aim for a solution viscosity of about 35 to 40 seconds, I think the solution concentration should be around 0.5% (5kg/m3).
The packaging is 25kg/bag.
*Please avoid using the recovered guar gum solution as it is as preparation water for stabilizing solution for earth drill piles.
Bentonite aggregates and does not suspend well.
Basically, we recommend disposal.
I’m going to make bentonite stabilizer now, but I can’t get tap water to use for mixing.
I have water delivered from a nearby ready-mixed concrete factory, but will there be any problems?
Basically, we believe that tap water, industrial water, and clean river water can be used as irrigation water without any problems.
However, there are two things you should be aware of when requesting a ready-mixed concrete factory.
①Do not use water to wash the ready-mixed concrete truck mixer. (It is full of Ca ions)
② The inside of the mixer of the ready-mixed concrete truck has been thoroughly cleaned. (The first shot is often contaminated water)
I would like to quickly remove the earth drill excavation residue (excavation waste that flows out), but is there a good reforming material?
The following methods come to mind:
①A long time ago, quicklime was used to forcibly evaporate water to lower the moisture content (the heat of hydration in quicklime is high and is not suitable for fire protection regulations).② Wait for the solidification reaction with a cement-based solidifying agent (
③ Composite type of quicklime and cement (less dangerous, relatively quick release possible, slightly more expensive) ④ Polymer
based modifier “Polyderac P” absorbs water and plasticizes soil (neutral type) , low additive amount, ready to dispense, relatively expensive)
⑤Polymer-based + mineral-based composite modifier “Sepat Soil S” absorbs water and plasticizes soil (new product, neutral system, ready to dispense, slightly more expensive) Comparison (There is room for consideration)
Recommended products: Polydelac P , Sepat Soil S , solidification material/soil improvement material
We are planning to improve the surface layer of the ground, but the target soil appears to be soft clay/organic soil.
Please let me know what improvement materials you recommend.
Please feel free to request a pre-mixing test from us.
We conduct tests according to the target strength of cement-based, lime-based, and composite systems.

Chemical injection related

I would like to know the relationship between the JIS No. of sodium silicate and liquid viscosity.
Viscosity No. 1 > No. 2 > No. 3 > No. 4 > No. 5 
The mainstream of inorganic injection agents these days are neutral injection agents that use sulfuric acid-based hardening agents, but what hardening agents are left that can be used as alkaline-based inorganic injection agents?
In the past, Aron and Sekisui were the mainstream, but due to the rising cost of raw materials, they are switching to sulfuric acid. There are several types in
existence, including the Sankopol series by Sanko Colloidal Chemical Co., Ltd. and the N-Tite series by Mitsubishi Chemical Infratech Co., Ltd.
Recently, organic solution type injection agents are being used less frequently, but I would like to know about the existing injection agents.
The use of organic products is currently permitted.
There are two main types: ethylene carbonate and glyoxal.
The former products include the Sankopol PSV series from Sanko Colloidal Chemical Co., Ltd. , and the latter products include the N-Tight Super series from Mitsubishi Chemical Infratech Co. , Ltd.
I would like to know if there are any suspension-type drug injections that have good penetration and durability.
Suspension-type chemical injection agents are generally considered to be difficult to penetrate into the interstices of the ground, but there are several types of penetration-type chemical injection agents that are mainly made of ultrafine slag.
The main material of these materials is finely powdered steel slag, so they are basically said to have permanent performance. There are also patterns that use water glass as a reactant and patterns that use non-water glass.
If water glass is used, it may not be permanent, but it is a special water glass type reactant that causes very little alkali leaching.
I would like to know the total cost of No. 3 sodium silicate used for chemical injection.
Liquid chemical injections are two-component chemicals that consist of a base agent and a hardening agent, and only after these two liquids are shot and hardened does it become a product.
Therefore, the cumulative price for the base agent, sodium silicate alone, is not disclosed.
The unit price for kneading the base agent and hardening agent is published as the unit price for ℓ.
Prices are set according to the type and purpose of the chemical solution, such as “solution type instant setting type” and “suspension type instant setting type.”
I think it is necessary to prevent hexavalent chromium from leaching out of the improved soil in advance during ground improvement work, but is this also necessary for chemical injection work?
Due to a notification issued in March 2000 targeting projects directly under the Ministry of Land, Infrastructure, Transport and Tourism, cement-based soils and improved soil using cement-based solidifying materials must be tested in advance under the Environmental Agency Notification No. 46 test for hexavalent chromium. must be carried out and satisfy soil environmental standards.
The target of the notification is not only the Ministry of Land, Infrastructure, Transport and Tourism, but also the Ministry of Agriculture, Forestry and Fisheries, Japan Highway Public Corporation, and others. In principle, this does not apply to local governments or private construction projects, but it is necessary to make the respective guidelines known.
Regarding chemical injection work, it basically applies to construction that uses cement, but as a general rule, it does not apply if it does not mix with the soil, and in the case of chemical injection work, it penetrates and mixes with the soil. If it is assumed that this is the case, the obligation will be required.
However, cement-based suspension-type drug injections are often excluded because they are instant-setting drugs that do not penetrate.
The “suspended permanent osmotic injection agent” introduced in the previous Q&A, “If there is a suspension-type drug injection agent that has good penetration and durability, please let me know.” is composed of a non-cement system. Therefore, we understand that this does not apply.
Reference material: Ministry of Land, Infrastructure, Transport and Tourism “Hexavalent chromium”
Is it okay to use seawater (or groundwater or river water mixed with seawater) for chemical injection and jet grouting when the only working water available on site is seawater?
In principle, clean water (tap water, industrial water, etc.) is preferable.
Chemical injection is absolutely prohibited because curing (gelation) is controlled by chemical reactions.
In the first place, when making liquid A, water glass reacts with seawater and becomes cloudy.
On the other hand, I think it is possible to use hardened milk for jet grouting.
Rather, it is said that the strength of cement milk development is increased by salt.
However, the function of the retardant is a chemical reaction, and it is thought that a slight deviation may occur, so sufficient consideration must be given when using it.
Please note that CB liquid, air milk, etc. cannot be used.
The area under the eaves of the factory has become vacant, and there appears to be a cavity in the ground. I want to fill a cavity, but is there any good material?
For filling cavities like this, we believe that materials that require time to harden, such as cement milk or CB liquid, are unsuitable.
We believe that a drug that can be tightly controlled to form a gel and that can be injected in limited quantities is suitable.
Such fillers are required to be semi-permanent. In addition, since it is preferable that the filler is not water glass-based, we recommend our product called “TM-G Filler.”
TM-G filler has instant setting type (10 seconds) and slow setting type (60 seconds).
The main hardening material, Material A, is blast furnace slag-based, and the gelling agent, Material B, is a special aluminum-based byproduct chemical (pH neutral), both of which are ecological products produced from byproducts.

promotion relationship

I would like to know how to add the plugging material “Atom Block” used for mud preparation in thick mud propulsion works.
In addition to “Atom Block” , please add the plugging material first.
In particular, “Atom Block” has extremely high dispersibility in clean water, but has poor dispersibility in viscous liquids and does not absorb water sufficiently.
When making mud, add it while water is being supplied to the mixer, and by the time the water supply is complete, it will be in a sufficiently dispersed state, so you can immediately add the slurry material.
During the thick mud propulsion project, when we approached hard clay ground, the jack speed decreased and the face plate felt like it was slipping.
I would like to deal with this problem using muddying materials, but are there any good additives?
It is well known that there are many different types of rock formations throughout Japan, depending on the region.
I know that the clay ground is too broadly categorized, but I have divided it into
1) hard clay
, 2) highly viscous soil,
and 3) soft clay .
I think it is difficult to dig into the ground in ① and ②, but to be honest, it is no exaggeration to say that there is no silver bullet.
However, it is necessary to deal with it, so our company responds with chemicals such as ㋐dispersant type, ㋑flocculant type, ㋒combination technique, and ㋓lubricant type.
㋐ In the dispersant system, it is simply dissolved in water and sent, but the greater the amount added, the greater the dispersion effect on clay soil.
⑑ Regarding the flocculant system, we expect it to have the effect of flocculating (soothing) clayey soil. There are differences in this reaction depending on the nature of the soil particles and the ionicity and molecular weight of the flocculant. Also, unlike the dispersant system mentioned above, it does not necessarily mean that the amount added is better; in our experience, we feel that lower viscosity solutions tend to be better.
On the other hand, in the lubricant system, we aim to activate the interface in cases where soil removal is difficult.
In either case, it is best to send only this solution dissolved in clean water, and we believe that it is unavoidable that the amount (ratio) of mud-making material (sludge-adding material) will increase.
There are differences in the amount of drug added and solution concentration, but please try within the range of 0.1 to 1.0%.
㋐Dispersant system: SARARI , Clean SP High Flow㋑Flocculant
system: Clean SP-H , SP-01 , Clean SP-HP
㋓Sliding material system: SP-R
Although CB liquid (cement ventonite liquid) is used for filling, pipe blockages, etc., breathing occurs.
1) Very little breathing
2) Can be pumped
3) Poor mix (low strength) mortar
4) Possible to cast underwater
Is there any material that meets the above requirements?
We recommend “TM300zero” .
It covers all the questions you may have, and it has low heat generation so you don’t have to worry about melting the PVC pipe.
In addition, since it is a low-cement product (the main material is blast furnace slag), it is a so-called low-carbon (CO2) product.
After all, it is a premixed product, so it is easy to handle (preparation) and requires no effort.
For more information, please refer to “Technology and Construction Methods” at the beginning of this website .
While excavating a clay layer using the muddy water propulsion (shield) method, the muddy specific gravity and viscosity of excavation waste (recovered muddy water) increased, reducing the efficiency of the filter press.
Is there a muddy water treatment additive that can replace PAC?
I would like to say that efficiency will be significantly improved, but there are processing chemicals that can relatively increase efficiency. Please try
“Soil Fresh” (manufacturer: Kurita Kogyo Co., Ltd.) .
Our sales staff and manufacturer engineers will also assist you during use.

Shield related

With two-component plastic backfilling (clean back method), I have set the gel time to be slow (15 seconds) considering the filling properties, but I would like to make the gel time a little faster (-5 seconds).What should I do? .
Gel time will change if you change the shot balance of liquid A (solidified material side) and liquid B (water glass side).
For example, changing the volume ratio from A:B = 8:2 to 9:1 will speed up the gel time. Conversely, if you change it to 7:3, the gel time will be slower.
In other words, reducing the amount of water glass in liquid B will make it faster, but since the amount of solidifying material will increase, the strength will also tend to increase. Conversely, increasing liquid B will slow down the process, but as the amount of solidifying material will decrease, the strength will decrease.
However, please note that if you reduce the amount of B solution too much, the gel strength will weaken, and if you increase it, the gel will become stronger and lose its plasticity, so be careful.
Please understand this as a trend.
During the mud pressure shield excavation, the ground is soft, so the excavation is possible with mud material that is almost like fresh water, and mud removal is smooth, but the machine head tends to lower.
I would like to correct the accuracy, but is there a better way?
To forcefully lift the machine head, why not try injecting “Clean FD II Type”, a solidified lubricant, from the bottom of the front body of the machine ?
It is originally a two-component solidified lubricant used in propulsion construction methods, but the gel time has been adjusted to 30 to 60 seconds, so it is a chemical that can be injected in limited quantities in hopes of uplifting the ground.
Please contact our sales representative regarding injection equipment.
During the excavation of the shield work, it became necessary to temporarily stop the excavation, so we wanted to fill the face and machine chamber with a self-supporting and non-hardening material.
Please suggest a good combination.
We recommend the “TGC method” .
“TGC” is an abbreviation for “Tatibana Gel Control” and is a mineral-based plastic filler whose gel strength can be adjusted as desired.
It is a filler material that can be used in a variety of situations, and it also performs outstandingly as a slurry material when excavating sandy and gravelly ground.
Please contact our sales representative regarding prescriptions.
Air mortar is being considered for secondary shield lining.
We would like to receive material proposals including equipment.
We will propose a mixture and equipment suitable for any amount of air, any strength, and on-site pouring conditions.
Air mortar casting methods are roughly divided into (1) base foaming method and (2) tip foaming method, but depending on the placement conditions of the sheath pipe, (2) tip foaming method is suitable for large-volume, long-distance construction. Masu.
For air mortar aggregates, we also offer bentonite , powdered clay (clay sand), and even “TM Powder” as a fine powder aggregate.
As for our main foaming agents, we have products from various surfactant manufacturers, so we can meet a variety of needs.
The mud pressure shield is being excavated, but the amount of excavation is not stable, probably due to the alternating layers of the ground.
Isn’t it possible to deal with this with muddy materials?
A high-viscosity muddying material is preferred for the gravel layer, and a low-viscosity muddying material is preferred for the clay-silt layer.
To address both, he recommends adding this drug.
What is that drug?

Please consult with our sales staff! !
What kind of automatic liquid preparation equipment and injection equipment can be prepared?
We own approximately 60 sets of working liquid batch plants and injection systems, both large and small.
In addition to this, we also have a wide variety of machines, including various silos, tanks, hoppers, foaming equipment, powder pneumatic transport equipment, and simultaneous backfilling injection pipes, although they are in niche areas.


Tachibana Materials seems to have an Ibaraki factory, but what kind of factory is it?
“Ibaraki Manufacturing Office” was opened in 2017 in the central industrial park in Ibaraki Prefecture.
We are a blending factory for civil engineering and construction materials, and in addition to manufacturing our own products, we also accept blending orders from our customers.
The other day at the Tachibana Materials equipment center, I saw a plant with an octagonal mixer, but I wonder where it was made.
“As expected of you!” That mixer is a mixing plant of “Ohmi Kiko Co., Ltd.”, an affiliated subsidiary of our company.
Since there are no stirring baffles inside the mixer, there is no leftover solidified material, etc., and of course, in terms of stirring accuracy, the efficiency is as good as if there were 8 baffles, and we have received high praise.
Are there any materials that can insolubilize soil contaminated with (containing) naturally occurring heavy metals?
“TM Guard” and “TM Lock” are representative insolubilizing materials.
However, the insolubilization of heavy metals in soil usually differs depending on the properties of each target soil, and basically, the formulation and materials are selected for each case depending on the purpose (insolubilization of various heavy metals, neutral range, securing strength). We are making suggestions.
Please feel free to contact us.
Please tell me about e-CEMEDAS.
For quality control of ground improvement work, we check the strength of samples taken after construction, but it usually takes a week to obtain the results.
This system uses the hydrochloric acid dissolution heat method to measure the amount of solidification material contained in improved soil.
The amount of cement mixed is estimated from the relationship between the calibration curve created in advance (during the mixing test) and the measurement results using samples collected during construction.
The measurement time is about 3 minutes, and results can be obtained during construction.