STABILIZATION ADDITIVE FOR SOILS WITH HIGH SULFATE CONTENT.

Abstract

The invention relates to additive soil stabilization applied in the geotechnical field to improve the engineering properties of soils. Specifically, the invention relates to an additive for stabilizing high sulfate-content soils, where workability and strength problems arise during stabilization with conventional calcium-based binders, using clinker and tartaric acid.

Description

STABILIZATION ADDITIVE FOR SOILS WITH HIGH SULFATE CONTENT. TECHNICAL FIELD The invention focuses on improving the engineering properties of soils in the geotechnical field. The invention relates to additive soil stabilization applied for this purpose. Specifically, the invention relates to conventional Processability and strength during stabilization with calcium-based binders. problems arise in soils with high sulfate content, clinker and tartaric acid. It relates to a contribution towards stabilization using [method / technology]. PREVIOUS TECHNIQUE Engineering specifications ensure the safety of structures to be built on or in it. Improving the soil that is insufficient for transporting the material in this way using appropriate methods This is necessary. One of the methods applied for this purpose is additive stabilization. The soil is engineered using additives such as cement, lime, and bitumen. The properties are being improved. However, cement and soils with high sulfate content... Stabilization with calcium-based additives such as lime prevents swelling of the soil. This can lead to problems such as swelling and fractures. These problems, It originates from ettringite and thaumacid compounds formed during stabilization and This negatively affects the strength of the soil. The reactions that occur are the same. Over time, stabilization reduces the workability of the mixture, resulting in a homogeneous mixture. This makes preparation difficult and creates various problems in field applications. It extracts. In cement production, clinker contains approximately 3-5% gypsum by weight. Plaster is added to prevent rapid hydration of tricalcium aluminate and to facilitate setting. It is used to keep the duration under control. However, it has a high sulfate content. When a soil is stabilized with cement, the ions present in the soil environment and the gypsum contained in the cement have an excessive sulfate effect on the tricalcium aluminate phase. This results in the formation of tricalcium aluminate, sulfate, and water. The equilibrium is disrupted, and the hydration reaction accelerates rapidly. The hydration reaction affects the workability of the mixture and the stabilized soil. This significantly reduces its strength. Therefore, traditional calcium-based... Direct use of binders, especially in soils with high sulfate content. This makes it difficult to carry out the stabilization process effectively. 1 THE PURPOSE OF THE INVENTION The purpose of the invention is to use cement in the stabilization of soils with high sulfate content. instead, by ensuring the combined use of clinker without added gypsum and tartaric acid. The goal is to reduce the effect of excessive sulfate. Another aim of the invention is to use clinker directly as an additive material. by using tartaric acid to limit the sudden formation of deposits. The aim is to improve the processability of the stabilization mixture by slowing down the hydration time. The invention also includes a homogeneous mixture of sulfate ground, clinker and tartaric acid. It aims to obtain and increase the strength of the stabilized soil. Thus, it will be carried out on or in soils with high sulfate content. to ensure that infrastructure and superstructure projects are carried out in a safe and long-lasting manner. a contribution is being made. DETAILED DESCRIPTION OF THE INVENTION The subject of the invention is a sulfate-based soil stabilization additive for soils with high sulfate content. Instead of cement containing gypsum, it is stabilized by using clinker directly and tartaric acid. It is based on the process of mixing clinker with gypsum, as in cement production. Avoiding its use reduces the excessive sulfate effect in the soil environment and prevents rapid setting. This helps to limit its formation. Tartaric acid, which is added to the mixture, It improves the workability of the mixture by slowing down the hydration time. With clinker The combined use of tartaric acid results in soils with high sulfate content. During stabilization, both processability and strength are improved. The amount of tartaric acid used as a stabilization additive is 2% of the clinker weight. It is in the range of 10%. In the preferred application, tartaric acid is 6% of the clinker weight. It is used in this proportion. The clinker used contains 21.20% SiO₂ and 4.324% Al₂O₃ by weight. 3.699% Fe₂O₃, 1.842% MgO, 1.108% K₂O, 0.195% Na₂O, 1.323% SO₃ and 0.0322% It contains Cl. The CaO content of clinker is in the range of 56.3-64.3% by weight, which is the preferred range. The CaO content is 60.3% by weight. The change in tartaric acid content affects the clinker composition. It is determined according to the change in the amount of CaO. The invention applies to soils with sulfate content exceeding 8000 ppm. It is used. The sulfate-treated substrate is first left to stand in an oven for 24 hours. The soil removed from the oven is ground in a grinder, then passed through a sieve to homogenize it. is being transformed into this state. 2 To the homogenized soil, clinker is added at a rate of 20% of the dry weight of the soil. Tartaric acid is added at a rate of 2-10% based on the weight of the clinker. is added to the mixture. In the preparation of the mixture, the water / clinker ratio is 2.5. It is determined. The prepared sulfate base, clinker, and tartaric acid are combined to obtain a homogeneous dry mixture. It is mixed in a mechanical mixer for about two minutes until it is cooked through. Then... Then pure water is added to the mixture of dry materials, and the mixture is heated at 150 rpm. It is mixed for three minutes using a mechanical mixer at a certain speed. The resulting mixtures are test samples suitable for the deep ground mixing method. It is used in the preparation. The prepared mixture is placed in containers with a diameter of 50 mm and a width of 100 mm. The samples are placed in cylindrical molds of a certain height. The samples can be easily removed from the molds. To facilitate removal, the inner surfaces of the molds are lubricated before the placement process. The sample is examined to remove air bubbles from the mixture. The molds are gently vibrated. The samples placed in the molds are removed after 24 hours. They are removed from the molds. The removed samples are placed at a temperature of 20±3°C and 70%. It is cured in a humid environment with relative humidity. Curing times are 7 days and 28 days. It is implemented as follows. After each curing cycle is complete, the samples are placed under pressure. They are subjected to experiments. Three samples are prepared for each experiment, and the experiments are conducted. This is repeated three times, starting with the drying of the sulfate-treated soil in the oven. grinding, sieving, mixing clinker with tartaric acid and pure water, molding placement, demolding, curing, and subjecting to unconfined compression testing. The processing steps leading up to the capture are shown in Figure 1. 3

Claims

1. Excessive sulfate during the stabilization of soils with high sulfate content. minimizing its effect, limiting sudden pressure build-up, hydration. slowing down the process and increasing the workability and strength of the soil It is a sulfate-based soil stabilization additive used for this purpose, and its characteristic feature is tartaric acid. It contains clinker without added gypsum, which contains acid.

2. According to Claim 1, it is an additive with the following characteristics: 21.20% SiO₂, 4.324% Al₂O₃, 3.699% by weight. Fe₂O₃, ranging from 56.3% to 64.3%, CaO, 1.842% MgO, 1.108% K₂O, 0.195% It is characterized by containing clinker with Na₂O, 1.323% SO₃ and 0.0322% Cl.

3. An additive according to Claim 2, characterized by preferably containing 60.3% CaO by weight. It is characteristic.

4. An additive according to claim 2 or 3, characterized by its tartaric acid content in the clinker. It is characterized by being present in an amount of 2-10% by weight.

5. According to claim 4, it is an additive with the characteristic of having a tartaric acid content of 6% by weight of the clinker. It is characterized by having a certain percentage. 4