• Title/Summary/Keyword: Low slump mortar

Search Result 23, Processing Time 0.023 seconds

The Effect of contiguous structure by the low slump mortar grouting (저유동성몰탈주입이 주변구조물에 미치는 영향)

  • 천병식;여유현;김진수;지원백
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2002.10a
    • /
    • pp.398-403
    • /
    • 2002
  • The low slump mortar grouting is widely used in reinforcement of structural foundation and ground improvement in soft ground. It also has merit that construction is possible in insufficient space. In this study, the main purpose is to evaluate effects for contiguous structures that can be happened along with soft ground improvement by the low slump mortar grouting. To estimate these effects, numerical analysis using finite difference method was applied. It was performed to analyze settlement, upheaval and horizontal displacement of surrounding ground and to measure horizontal stress variation by the first and the second grouting in the pile foundation.

  • PDF

Reinforcement of Building Foundation by the Low Slump Mortar Grout (저유동성 몰탈형 주입재에 의한 건물기초보강)

  • 천병식;고용일;권형석
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2000.11a
    • /
    • pp.71-76
    • /
    • 2000
  • In generally, grouting consists of injecting a suspension or solution into the voids of soils. The low slump mortar grout has been used in America since 1950's. The Compaction Grouting, the injection of a very stiff under relatively high pressure, form a cylinderical grout support pile. The grout generally does not enter soil pores but remains in homogeneous mass that gives controlled displacement either to compact loose soils, or for lifting of structures, or both. In this paper, on the case of the reinforcement construction of 00 plant that the foundation's bearing capacity is insufficient and is to reinforce the foundation, a study has been peformed to analyze the effectiveness of the ground improvement. The bearing capacity of the Compaction Pile has been verified by the S.P.T and the settlement of the improved ground has been monitored rising the magnetic extensometer.

  • PDF

A Study on the Deformation of Ground by the Low Slump Mortar Grouting (저유동성 몰탈주입 적용지반의 거동에 관한 연구)

  • Do, Jongnam;Lee, Jinkyu;Chun, Byungsik
    • Journal of the Korean GEO-environmental Society
    • /
    • v.11 no.10
    • /
    • pp.5-13
    • /
    • 2010
  • Low slump mortar grouting is widely used in reinforcement of structural foundation and ground improvement in soft ground, and has advantage which construction is possible in insufficient space. However it has been not yet studied sufficiently to estimate the effect of ground improvement in design step and to prove the estimating method. So the method must be developed in order to use the low slump mortar grouting method in various cases. In this study, the field tests were performed in the reclaimed soils to measure the effect of ground improvement. Then it was compared with what was calculated by the existing formula that was formerly suggested. The results show that the value from the formula was similar with the value from the field tests. Also it was proved that the formula was available to estimate the effect of ground improvement in the loose granular soils.

A Study on the Properties of Low-Heat Cement Concrete (저발열시멘트 콘크리트의 기초적 성질에 대한 연구)

  • 문한영;김성수;신화철;강석화
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 1997.10a
    • /
    • pp.57-60
    • /
    • 1997
  • The properties of Low-heat cement are especially in lower heat of hydration than that of other types of cement. In other respect, Low-heat concrete is more advantageous than OPC concrete in chemical resistance, long term age compressive strength, slump loss and resistance to seawater. This paper deals with 28 days age compressive strength and slump loss by elapsed time of mortar and concrete that made with Low-heat cement and 3 types of other cement.

  • PDF

Characteristics of Ground Improvement by Compaction Grouting System in Filled Ground (매립토층에서 CGS에 의한 지반개량특성에 관한 연구)

  • 천병식;여유현;정영교;정완균;정의원;김우종
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2001.03a
    • /
    • pp.425-432
    • /
    • 2001
  • Compaction Grouting System, the method which makes ground compact by injection of low slump mortar, Is widely used for reinforcement of soft ground, restoration of structures happened differential settlement, underpinning and restoration of damaged dam core. The quantitive analysis of ground improvement for this method has not performed yet. So, design parameters about thls method must be studied through performance of CGS in various types of soil to make CGS adaptable widely. In this study PBT, SPT and field density test were performed for analysis of the characteristics of ground improvement and pressuremeter and inclinometer were installed for analysis of the characteristics of compaction in adjacent ground. In this paper, denoted much effects for filled ground that increasing of the bearing capacity, confirming the displacement of adjacent ground and the effective radius of injection.

  • PDF

The Study on the Stress Concentration Ratio of Low Slump Mortar Grouting Mixtures for Improving the Soft Ground (연약지반 보강을 위한 저유동성 몰탈 개량체의 응력분담비에 관한 연구)

  • Park, Eonsang;Kim, Byungil;Park, Seungdo
    • Journal of the Korean GEO-environmental Society
    • /
    • v.21 no.9
    • /
    • pp.15-24
    • /
    • 2020
  • In this study, the stress concentration ratio for the improved material of the low slump mortar grouting was evaluated through the composite ground method, the ground arching theory, the plastic angle method, the 2D and 3D numerical analysis and the 3D model experiment. The stress concentration ratio calculated by the composite ground method was 89.3, 3.75~59.0 when the three-dimensional ground arching theory was applied, and 82.8 for the three-dimensional plastic angle method. As a result of the 2D numerical analysis, the stress concentration ratio was 63.0~77.0, which was found to increase as the improvement ratio increased. The results of 3D numerical analysis were predicted to be 50.0~56.0 smaller than the results of 2D analysis. In the case of a special model experiment using a large triaxial compression cell, the stress concentration ratio for each load step was 53.0~60.0, and the stress concentration ratio evaluated by the experiment was measured within 2D and 3D numerical analysis predictions. In this study, a predictive equation for the stress concentration ratio according to the improvement ratio is proposed based on the analysis and experimental values for the improved ratio of the low slump mortar grouting.

Settlement Restraint of Soft Ground by Low Slump Mortar Injection (저유동설 몰탈주입에 의한 연약지반의 침하억제 효과)

  • 천병식;여유현;정영교
    • Journal of the Korean Geotechnical Society
    • /
    • v.17 no.6
    • /
    • pp.53-67
    • /
    • 2001
  • In this study the pilot test of CGS as injection method by low slump mortar was performed and the results were analyzed in order to find out the application of this method and effect of settlement restraint. The site far pilot test is adjacent to apartments supported by pile foundations. Sand drain method was performed previously as countermeasures against settlement, but settlement occur continuously because this ground is very soft. Site investigations such as SPT, DCPT and vane shear test were performed to determine the characteristics of ground improvement. Field measurements and FDM analysis were performed on purpose to find out the displacement of ground during injection works. From the results of this study, CGS method can be optimized by the control of diagram, space, depth, injection material, and injection pressure. CGS improved soft ground compositely by the bearing effect of CGS columns and reinforcement of adjacent ground. Considering that increase of N value is about 2.1, CGS can be considered as an effective method to increase the bearing capacity as well as to stop the settlement of soft ground. It is also expected to be economic and effective in improvement of ground when it is used in applicable sites.

  • PDF

Case Study for Improvement of Marine Clay and Dredgedfill Ground by CGS Method (CGS공법에 의한 해성점토 및 준설매립지반의 기초보강 사례)

  • Shin, Eun-Chul;Chung, Duek-Kyo;Seo, Kui-Chang;Lee, Myung-Shin
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2010.03a
    • /
    • pp.480-488
    • /
    • 2010
  • The CGS method is non-discharge replacement method improving ground stiffness by the effect of static compaction with injecting very low slump mortar into ground, and is applied for increasing bearing capacity and filling ground cavity by lifting or restoring differential settled structures and preventing differential settlement. This paper suggests design of ground improvement and construction case history for civil engineering structures by CGS method. This method can be used for reinforcing soft ground and liquefaction of loose sandy soil. This method was used in SongDo area in Incheon Economic Free Zone due to its low vibration of ground while it can improve the soft soil where underground structures(subway and box culvert) are already existed.

  • PDF

A Study on the Comparison of Physical Properties of OPC and Low-Heat Cement for the Evaluation of Concrete Properties of Low-Heat Cement Using Non-Carbonate Raw Materials (비탄산염 원료 활용 저열시멘트 콘크리트 물성 평가를 위한 OPC와 저열시멘트의 물성 비교에 관한 연구)

  • Kwon, Min Su;Heo, Jong-Wan
    • Cement Symposium
    • /
    • s.49
    • /
    • pp.31-32
    • /
    • 2022
  • This study is to analyze the difference by comparing the physical properties of general Portland cement (OPC) and low-heat Portland cement (LHC) in the market to develop low-heat cement manufacturing technology that can minimize the amount of limestone by using non-carbonate circulating resources as raw materials. To this end, the mortar is being reviewed by evaluating the properties of the mortar, such as slump, strength, durability, and thermal insulation properties, with a difference in the mixing ratio.

  • PDF

Freeze and Mechanical Properties of Cement Mortar Using Coolant Wastes (폐부동액을 이용한 콘크리트의 동결 및 역학적 특성)

  • 김상우;김정진;홍상희;전충근;한천구
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 2000.10a
    • /
    • pp.555-558
    • /
    • 2000
  • It has been increasingly proving in interest of environment pollution around the world. so, recycling of waste resources are seriously taken into consideration. Great deal of coolant for the car have been wasted for along time. due to the end of life time of them. Therefore, validities of wasted coolant as an agent for concrete are described in this paper. Mechanical properties of concrete using coolant wastes is investigated. As contents of coolant wastes increase, slump and slump flow decrease, while air content show reverse tendency. setting time shows to be accelerated with increase of waste contents. As for the effect of low curing temperature, low curing temperature increase compressive strength with increase of coolant waste. Application of coolant waste to cold weather concrete is considered to achieve favorable effects.

  • PDF