scholarly journals Model Tests on the Retaining Walls Constructed from Geobags Filled with Construction Waste

2016 ◽  
Vol 2016 ◽  
pp. 1-13 ◽  
Author(s):  
Hua Wen ◽  
Jiu-jiang Wu ◽  
Jiao-li Zou ◽  
Xin Luo ◽  
Min Zhang ◽  
...  

Geobag retaining wall using construction waste is a new flexible supporting structure, and the usage of construction waste to fill geobags can facilitate the construction recycling. In this paper, model tests were performed on geobag retaining wall using construction waste. The investigation was concentrated on the slope top settlement, the distribution characteristics of the earth pressures on retaining walls and horizontal wall displacements, and slope failure modes. The results indicated that the ultimate loads that the slope tops with retaining walls could bear were 87.5%~125% higher than that of the slope top without retaining walls. The ultimate loading of strengthened slopes with different slope ratios from 1 : 0.75 to 1 : 0.25 could be reduced by 11.8% to 29.4%. The horizontal displacements of the retaining walls constructed from geobags were distributed in a drum shape, with the greatest horizontal displacements occurring about 1/3~1/2 of the wall height away from the bottom of the wall. As the slope ratio increased, the failure of the slope soil supported by geobag retaining wall using construction waste changed from sliding to sliding-toppling (dominated by sliding) and then to toppling-sliding (dominated by toppling). The range of 1/3~1/2 of wall height is the weak part of the retaining walls, which should be strengthened with certain measures during the process of design and construction.

Author(s):  
Rizki Ramadhan ◽  
Munirwansyah Munirwansyah ◽  
Munira Sungkar

The Aceh Tengah / Gayo Lues-Blangkejeren road segment (N.022) Km 438 + 775 is one of the Central Cross National Roads in the Province of Aceh, which often experiences landslides due to being in hilly areas. Landslides that occur in these locations are caused by scouring of road runoff, lack of optimal drainage and the absence of outlets for drainage and soil layers under asphalt pavement consisting of loose material. Therefore, a slope reinforcement study with Counterfort type retaining wall is needed. This study aims to analyze slope stability by obtaining safety factor numbers and identifying slope failure patterns. Analysis was carried out to obtain safety factors and slope failure patterns by using 2D Plaxis and slice methods. The calculation of safety factors for Counterfort type retaining walls is done manually. The input soil parameters used are dry volume weight (gd), wet volume weight (gw), permeability (k), modulus young (Eref), paisson's ratio (υ), shear angle (f), cohesion (c) . The results of slope stability analysis on the existing conditions using the Plaxis program and the slice method with radius (r) 65.06 meters found that safety factors were 1.038 and 1.079 with unsafe slope conditions (FK <1.25). The results of the analysis after reinforced counterfort and minipile type retaining wall with a length of 12 meters found 1,268 safety factor numbers with unsafe slope conditions (FK <1,5). Thus, additional reinforcement is needed by using anchor on the counterfort. The results of slope stability analysis after reinforced counterfort, minipile and anchor type retaining walls with a length of 20 meters and a slope of 30 ° were obtained with a safety factor number of 1.513 with safe slope conditions (SF> 1.5).ABSTRAKRuas jalan batas Aceh Tengah/Gayo Lues-Blangkejeren (N.022) Km 438+775 merupakan salah satu ruas jalan Nasional Lintas Tengah Provinsi Aceh, yang sering mengalami terjadi tanah longsor karena berada di daerah perbukitan. Longsoran yang terjadi pada lokasi tersebut disebabkan oleh gerusan air limpasan permukaan jalan, kurang optimalnya drainase dan tidak adanya outlet untuk pembuangan air serta lapisan tanah di bawah perkerasan aspal terdiri dari material lepas. Oleh karena itu, diperlukan kajian perkuatan lereng dengan dinding penahan tanah tipe Counterfort. Kajian ini bertujuan untuk menganalisis stabilitas lereng dengan mendapatkan angka faktor keamanan dan mengidentifikasi pola keruntuhan lereng. Analisis dilakukan untuk mendapatkan faktor keamanan dan pola keruntuhan lereng yaitu dengan menggunakan program Plaxis 2D dan metode irisan. Perhitungan faktor keamanan untuk dinding penahan tanah tipe Counterfort dilakukan secara manual. Adapun parameter  tanah input yang digunakan adalah berat volume kering (gd), berat volume basah (gw), permeabilitas (k), modulus young (Eref), paisson’s rasio (υ), sudut geser (f), kohesi (c). Hasil analisis stabilitas lereng pada kondisi eksisting menggunakan program Plaxis dan metode irisan dengan jari-jari (r) 65,06 meter didapatkan akan faktor keamanan sebesar 1,038 dan 1,079 dengan kondisi lereng tidak aman (FK < 1,25). Hasil analisis setelah diperkuat dinding penahan tanah tipe counterfort dan minipile dengan panjang 12 meter didapatkan angka faktor keamanan 1,268 dengan kondisi lereng tidak aman (FK < 1,5). Dengan demikian, maka diperlukan perkuatan tambahan dengan menggunakan angkur pada counterfort. Hasil analisis stabilitas lereng setelah diperkuat dinding penahan tanah tipe counterfort, minipile dan angkur dengan panjang 20 meter serta sudut kemiringan 30° didapatkan angka faktor keamanan 1,513 dengan kondisi lereng aman (SF > 1,5).Kata kunci : longsoran; counterfort; plaxis 2D; faktor keamanan.


Retaining walls are structures used not only to retain earth but also water and other materials such as coal, ore, etc. where conditions do not permit the mass to assume its natural slope. In this chapter, after considering the types of retaining wall, earth pressure theories are developed in estimating the lateral pressure exerted by the soil on a retaining structure for at-rest, active, and passive cases. The effect of sloping backfill, wall friction, surcharge load, point loads, line loads, and strip loads are analyzed. Karl Culmann's graphical method can be used for determining both active and passive earth pressures. The analysis of braced excavations, sheet piles, and anchored sheet pile walls are considered and practical considerations in the design of retaining walls are treated. They include saturated backfill, wall friction, stability both external and internal, bearing capacity, and proportioning the dimensions of the retaining wall. Finally, a brief treatment of earth pressure on underground structures is included.


2019 ◽  
Vol 2 (2) ◽  
pp. 116-126
Author(s):  
Tsuyoshi Nishi ◽  
Tadashi Hara ◽  
Hiroshi Nakazawa ◽  
Daisuke Suetsugu

In developing countries, gabions are widely used in several construction works, like road, river, countermeasures against slope failure and so on, because of their easy operation and low cost. In 2015 Nepal Gorkha Earthquake, a lot of retaining walls using gabions were not damaged against the strong earthquake because of their high flexibility. However, some deformation or declination were reported dpending on retaining wall types and ground conditions behind retaining walls. Therefore, in order to evaluate the earthquake resistance and residual deformations of retaining walls using gabions widely observed in Nepal, full-scale shake table tests and laboratory tests were conducted in previous studies. In this study, elemental simulations for determination of the analysis parameters based on the results of triaxial compression tests were carried out to check the validity of parameters. Then, a series of numerical analysis using proposed model was performed to reproduce the dynamic behaviors of full-scale shake table tests and evaluate the earthquake resistance of retaining wall using gabions. According to the results of these numerical analysis, it was confirmed that proposal model adequately could simulate the dynamic response of retaining walls in the full-scale shake table tests. and it was also cleared that the stepwise type retaining wall was superior to that of vertical type from the standpoint of earthquake stability against sliding and overturning.


2020 ◽  
Vol 30 (3) ◽  
pp. 214-233
Author(s):  
Fatima Zohra Benamara ◽  
Ammar Rouaiguia ◽  
Messaouda Bencheikh

Abstract Anchored retaining walls are structures designed to support different loading applied in static and dynamic cases. The purpose of this work is to design and study the stability of an anchored retaining wall loaded with different seismic actions to obtain minimal anchor lengths. Mononobe-Okabe theory has been applied for the evaluation of seismic earth pressures developed behind the anchored wall. Checking the dynamic stability of anchored retaining walls is usually done using the classic Kranz model. To take into consideration the effects of the internal forces developed during failure, we have proposed a new model, based on the Kranz model, which will be used as the Kranz model to find the critical angle failure performed iteratively until the required horizontal anchor length is reached for a minimum safety factor. The results of this study confirm that the effect of the seismic load on the design of an anchored retaining wall, and its stability, has a considerable influence on the estimation of anchor lengths. To validate the modifications made to the new model, a numerical analysis was carried out using the Plaxis 2D software. The interpretation of the obtained results may provide more detailed explanation on the effect of seismic intensities for the design of anchored retaining walls.


2021 ◽  
Vol 13 (1) ◽  
pp. 570-581
Author(s):  
Meriem F. Bouali ◽  
Mahdi O. Karkush ◽  
Mounir Bouassida

Abstract The general assumption of linear variation of earth pressures with depth on retaining structures is still controversial; investigations are yet required to determine those distributions of the passive earth pressure (PEP) accurately and deduce the corresponding centroid location. In particular, for rigid retaining walls, the calculation of PEP is strongly dependent on the type of wall movement. This paper presents a numerical analysis for studying the influence of wall movement on the PEP distribution on a rigid retaining wall and the passive earth thrust location. The numerical predictions are remarkably similar to existing experimental works as recorded on scaled test models and full-scale retaining walls. It is observed that the PEP varies linearly with depth for the horizontal translation, but it is nonlinear when the movement is rotational about the top of the retaining wall. When rotation is around the top of the wall, the resultant of PEP is located at a depth that varies between 0.164 and 0.259H of the wall height measured from the base of the wall, which is lesser than 1/3 of the wall height. The passive earth thrust location is highly affected by the soil–wall friction angle, especially when the friction angle of the backfill material increases. Despite the herein presented results, further experiments are recommended to assess the corresponding numerical predictions.


2010 ◽  
Vol 168-170 ◽  
pp. 200-205
Author(s):  
Fei Song ◽  
Jian Min Zhang ◽  
Lu Yu Zhang

The evaluation of earth pressure is of vital importance for the design of various retaining walls and infrastructures. Experimental studies show that earth pressures are closely related to the mode and amount of wall displacement. In this paper, based on the reveal of the formation mechanism of earth pressures against rigid retaining wall with RTT mode, a new method is proposed to calculate the earth pressure distribution in such conditions. Finally, the effectiveness of the method is confirmed by the experimental results.


1982 ◽  
Vol 19 (3) ◽  
pp. 213-224 ◽  
Author(s):  
W. F. Anderson ◽  
T. H. Hanna ◽  
D. A. Ponniah ◽  
S. A. Shah

Laboratory-scale tests simulating field construction procedures have been carried out to examine the behaviour of the soil–wall–anchor system when a rigid retaining wall, restrained by anchors, supports a sand backfill on which there is surface loading. Two main series of tests have been carried out, one with a uniform load applied over the whole backfill surface, and the other with a strip load applied parallel to the wall and at a varying distance from it. In both series of tests the intensity of loading was varied, and in the series with uniform loading on the backfill the effects of varying anchor inclination were studied. During all stages of construction wall movements, earth pressures, anchor loads, wall base reaction, and backfill surface subsidence were monitored. Although a conservative approach was used in the determination of the anchor loads, wall movements, and consequently backfill subsidence, were considerable. Similar movements at full scale could lead to settlement damage in a structure founded on a shallow mat or strip footings on a backfill, so tentative suggestions are made for more conservative earth pressure distribution assumptions for design purposes for the two cases studied.


2021 ◽  
Vol 11 (18) ◽  
pp. 8681
Author(s):  
Xiaoguang Cai ◽  
Shaoqiu Zhang ◽  
Sihan Li ◽  
Honglu Xu ◽  
Xin Huang ◽  
...  

Most of the damage to reinforced retaining walls is caused by excessive deformation; however, there is no calculation method for deformation under static and dynamic loads in the design codes of reinforced soil retaining walls. In this paper, by collecting the measured displacement data from four actual projects, four indoor prototype tests and two indoor model tests under a total of 10 static load conditions, and comparing the calculation results with seven theoretical methods, the results show that the FHWA method is more applicable to the permanent displacement prediction of indoor prototype tests and that the CTI method is more applicable to the permanent displacement prediction of actual projects and indoor model tests. Two yield acceleration calculation methods and four permanent displacement calculation formulas were selected to calculate the displacement response of two reinforced soil test models under seismic loads and compared with the measured values, and the results showed that the Ausilio yield acceleration solution method was better. When the input peak acceleration ranges from 0.1 to 0.6 g, the Richards and Elms upper limit method is used, and when the input peak acceleration is 0.6–1.0 g, the Newmark upper limit method can predict the permanent displacement of the retaining wall more accurately.


2018 ◽  
Vol 2 (2) ◽  
pp. 86
Author(s):  
Mila K. Wardani ◽  
Felicia T. Nuciferani ◽  
Mohamad F.N. Aulady

Landslide one of the natural disasters that caused many victims. Therefore, the landslide need a construction that can withstand landslide force. This study aims to plan retaining walls to prevent landslides in the farm area in Kandangan Subdistrict, Kediri Regency. The method used is to use slide analysis which is used to plan the retaining wall. In addition the planning of soil containment walls u ses several methods as a comparison. The results of this study indicate that the planning of ordinary soil retaining walls is still not enough to overcome slides. The minimum SF value that meets the safe limit of landslide prevention is 1.541 in the combination of 1/3 H terracing and the number of gabions as many as 7 with a total height of 2- 3 m .


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