Construction Of Retaining Walls Research Articles

Increase in Safety Factor Value in Existing Conditions and Reinforcement of Gabion Type Retaining Wall Pt. Medco E&P Malaka Block A

Indonesia is an archipelagic country with 34 provinces, which has a diverse soil profile and geological structure. This condition is an area where a slope is formed. The slope is a sloping land surface and forms a certain angle and has no force in resisting the occurrence of a slide. Landslide is a disaster that can cause casualties. Collapse (slide) occurs as a result of a driving force greater than the opposite force originating from the shear strength of the soil. The slide occurred at PT. Medco E&P Malaka Block A, Ranto Perlak District, East Aceh Regency, Aceh Province in the Siwah flow ROW STA 2+400. Landslides occur as a result of high rain intensity resulting in landslides. The safety factor analysis on the slopes was carried out using the Strength Reduction Method (SRM). In the existing conditions, the slope experienced a collapse (slide) with an SF value of 1.15, which did not meet the requirements of the safety factor value (SF≥ 1.25). Therefore, reinforcement was carried out on this slope by constructing a Gabion type retaining wall construction with a height of 3 m and a width of 1.5 m. From the analysis with Gabion type retaining wall reinforcement, the SF value was 1.51 which fulfilled the requirements of the Safety factor when strengthening (SF≥ 1.5). From this analysis, it was found that the SF value was different in the existing conditions, the SF value was 1.15 and in the strengthening condition, the SF value was 1.51. Where the SF value increases by 0.36 or 32%.

Investigation of the Effects of Engineering Properties of the Backfill Material Used in the Construction of Geogrid-Reinforced Retaining Wall on Factors of Safety on a Case Study

Bu çalışmada, yapımı tamamlanmış ve hizmete açılmış bir karayolu güzergâhında bulunan geogridle güçlendirilmiş istinat duvarlarına ait tasarım parametreleri kullanılarak dolgu malzemesi için tahmine dayalı olarak seçilen içsel sürtünme açısı ve birim hacim ağırlık gibi parametrelerin geogridin kopmaya ve sıyrılmaya karşı güvenlik katsayıları üzerindeki etkileri incelenmiştir. Yapılan analizler sonucunda, içsel sürtünme açısı arttığında kopmaya ve sıyrılmaya karşı güvenlik katsayılarında artış meydana geldiği ve sıyrılmaya karşı güvenlik katsayılarının kopmaya karşı güvenlik katsayılarından daha yüksek çıktığı görülmüştür. Bu bakımdan tasarım hesaplarında, kopmaya karşı güvenlik katsayısının daha kritik olduğu ve tasarımı kontrol eden asıl faktörün kopmaya karşı güvenlik katsayısı olduğu sonucuna varılmıştır. Bununla birlikte, sıyrılmaya karşı güvenlik katsayısının kopmaya karşı güvenlik katsayısına kıyasla içsel sürtünme açısının değişimlerinden daha fazla etkilendiği görülmüştür. Örneğin, içsel sürtünme açısında %15’lik bir artış, kopmaya karşı güvenlik katsayısında yaklaşık %30 oranında bir artışa neden olurken, sıyrılmaya karşı güvenlik katsayısında, z = 1,2 m’de yaklaşık %310, z =10 m’de ise yaklaşık %60’lık bir artışa neden olmuştur. Dolgu malzemesinin birim hacim ağırlığındaki değişimlerin kopmaya ve sıyrılmaya karşı güvenlik katsayıları üzerindeki etkisinin yüksek olmadığı (sırasıyla yaklaşık %10 ve %3) görülmüştür. Kendi aralarında kıyaslandığında, dolgu malzemesinin birim hacim ağırlığındaki değişimlerin, kopmaya karşı güvenlik katsayısı üzerindeki etkisinin sıyrılmaya karşı güvenlik katsayısı üzerindeki etkisinden daha yüksek olduğu görülmüştür.

The Construction of a Gravity Retaining Wall to Prevent Landslides on the Grogol Kediri Highway

One proof of Kediri's progress is the construction of Doho Kediri International Airport which is expected to improve the economy and tourism in this city. The airport was built with the aim of improving connectivity and suppressing development disparities in southern East Java. The purpose of this study is to plan the construction of an earthquake-resistant which is gravity retaining wall on the Grogol Kediri Highway, Kediri Regency. . Planning is carried out at STA 3.8-4.0. , soil laboratory testing on samples obtained from the studied location. Identification of the soil type, sliding angle, and weight of the soil volume at the site are needed to determine the planning of earthquake-resistant retaining walls. From the soil properties obtained, it can be determined that the land is included in the GC (Clayey Gravel) category With a shear angle of 28° and a weight of 1.463 gr/cm3. These results were used to calculate the dimensions and the stability of the retaining wall using the Coulomb method. The retaining wall should have a peak body width of 1 meter, foundation width of 3.8 meters, foundation thickness of 1 meter, foundation depth of 1.04 meters, foot and heel width of 0.9 meters, height of 6 meters, and bottom body thickness of 2 meters. Based on stability calculations, the retaining wall is safe against overturning, shifting, and subsidence. Therefore, this retaining wall is a viable solution to prevent landslides and mitigate the negative impacts caused by them.

Improvement of an existing building shallow foundation using soil nails supported retaining wall: A numerical assessment

In recent years, the need to expand the land area for infrastructure development, such as roads and streets near residential buildings, in urban areas in Vietnam has become more widespread. Such tendency leads to narrowing of the space available for further development thus the ground condition around existing buildings often need improvement. The foundations of existing buildings can no longer bear additional stresses. In such cases the foundation and the ground conditions need engineering solutions to provide geotechnical safety. The present paper presnts a numerical anlyses of soil nailing, to enhance the stability of the foundation of an existing building constructed on firm clay soil. The finite element method was empolyed to compute the stability of the foundation with/without incorporating soil nail reinforcements. Additionally, the analyses concern also the retaining wall construction to assure long-term performance of proposed scenarios. The numerical computation results indicate that the stability of the foundation improved by soil nailing was not enough to meet the ultimate limit state. The combination of a retaining wall supported by soil nails increased the factor of safety to a value considered sufficient. The settlements, as well as the horizontal displacements analyses proved the correctness of proposed solutions.

DESIGNING A TRAPEZOIDAL MODULAR BLOCK WALL WITH NONLINEAR OPTIMIZATION

A rectangular wall is better in terms of stability and ease of calculation than a trapezoidal wall. However, a trapezoidal wall is sometimes inevitable such as a retaining wall construction near rockface. FHWA provides simplified rules to design a trapezoidal wall. However, FHWA does not give an example to follow, and the rules need trial and error to implement. BS8006 gives an exact dimension of the block heights, but designing still needs to adjust the block widths. A 16-meters high modular block wall project near rock face in Thailand as an example to illustrate a calculation detail in external stability checking follow FHWA simplified rules and BS8006. The illustrations are trapezoidal walls with two zones, three zones, and four zones. Nonlinear optimization models are also used to minimize the wall base length to facilitate the construction instead of jacking the near rock face to build a rectangular wall. Optimization models also help to relax FHWA simplified rules and BS8006 guidelines. Using an optimization model can decrease the base length from 0.7H to 0.6H for a rectangular wall or even 0.5H for a rectangular wall with competent foundation soil. Optimization models can also achieve a base length down to 0.48H with a decrease in the cross-sectional area down to 0.92 for a three zones trapezoidal wall. A simple three zones wall with exact dimensions is also proposed in the competent foundation soil conditions.

Key Points of Quality Control of Mountain Highway Retaining Wall Construction

Key Points of Quality Control of Mountain Highway Retaining Wall Construction

Load transfer on instrumented prestressed ground anchors in sandy soil

abstract: This study evaluates load variations in instrumented prestressed ground anchors installed in a bored pile retaining wall system in sandy soil. Data were collected from instrumentation assembled in the bonded length of three anchors, which were monitored during pullout tests and during different construction phases of the retaining wall system. Instrumentation consisted of electrical resistance strain gauges positioned in five different sections along the bonded length. Skin friction distributions were obtained from the field load measurements. Results showed that the skin friction followed a non-uniform distribution along the anchor bonded length. The mobilized skin friction concentrated more intensely on the bonded length half closest to the unbonded length, while the other half of the bonded length developed very small skin friction. The contribution of the unbonded length skin friction to the overall anchor capacity was significant and this should be accounted for in the interpretation of routine anchor testing results. Displacements applied to the anchor head were sufficient to mobilize the ultimate skin friction on the unbonded length, but not on the bonded length. Performance of loading-unloading stages on the ground anchor intensified the transfer of load from the unbonded length to the bonded length. Long-term monitoring of the anchor after lock-off revealed that the load at the anchor bonded length followed a tendency to reduce with time and was not significantly influenced by the retaining wall construction phases.

Active earth pressure of narrow cohesive backfill on rigid retaining wall of rotation about the bottom

Retaining wall construction often encounters narrow cohesive backfill and the traditional theories are no longer suitable. Hence, analytical solutions for active earth pressure of narrow cohesive backfill on a rigid retaining wall rotating about the bottom are proposed in this paper. The principle stress rotation caused by interface friction is also included. Through a typical FEM analysis and analytical derivation, the multi-segmented failure surface composed of a logarithmic spiral curve in the lower part and a tangent line in the upper part is quantitatively determined. According to the aspect ratio of the narrow backfill, three basic failure models of the narrow cohesive backfill are found together with three types of differential elements. A program is coded to automatically identify these three failure models to quickly obtain the distribution, the resultant and the application point of the active earth pressure. The proposed analytical solutions are then verified through a two-step procedure of elaborate comparisons with the FEM results and good agreements are observed. Subsequently, a parametric investigation indicates the active earth pressure is positively correlated to the aspect ratio and slope inclination angle, while is negatively correlated to the soil cohesion and interface friction.

The study of configuration effect of helical anchor group on retaining wall displacement

ABSTRACT Despite numerous applications of helical anchors in slope stabilisation and retaining wall construction, a limited number of studies have been conducted on their performance. In the present study, the results of investigating 4 types of helical anchors and three configurations of reinforcement are presented. The tests were carried out on sandy soil using a test box, load cell, indicator, and 5 dial gauges. The present work aims to evaluate the effect of anchor geometry and its configuration on wall displacement. In all tests, particle image velocimetry (PIV) method was applied to study the shape of the slip surface. The results showed that diamond configuration outperforms square one in terms of bearing capacity, wall crest displacement, and its deformation. Moreover, in all tests, an increase in the number of helices resulted in a descending trend in bearing capacity increase and a decrease in wall displacement, suggesting the reduction of efficiency by increasing the number of plates. The results also show that anchor configurations and the number of helices are more effective than the number of anchors in increasing the bearing capacity.

Use of construction and demolition solid wastes for basket gabion filling.

Construction and demolition wastes have been studied by technical means aiming at the development of management tools to reduce their environmental impacts. Among these, recycling can be highlighted. This paper aims at the technical assessment of basket gabions filled with construction and demolition solid waste. Gabions are usually used for retaining walls construction, and these are commonly filled with rocks. Retaining walls are essential for earthfill slopes stabilization, and they must have proper characteristics of strength. However, depending on the slope height or the technical responsibility of the retaining wall, alternative materials with proper characteristics could be used to fill the gabions. The use of recycled material for gabion filling could reduce environmental impacts and costs caused by retaining wall construction. So, basket gabion cells were filled with construction solid waste and basaltic rocks, both crushed into coarse granulometry aiming to compare technical characteristics among them. The performed laboratory tests showed that the horizontal and vertical displacements determined for gabion filled with wastes were near to those obtained for gabions filled with basaltic rocks for a retaining wall of 5 m and up. In conclusion, it can be drawn that basket gabions filled with construction and demolition waste may be a technical alternative for civil construction, reducing environmental impacts and raw material consumption for retaining wall execution.

Development and Application of Precast Concrete Double Wall System to Improve Productivity of Retaining Wall Construction

The construction of most apartment underground parking lots utilizes reinforced concrete (RC) structures composed mainly of rebar work and formwork. RC structures lower construction efficiency and significantly delay the construction because they require a large number of temporary materials and wooden formwork. In this study, a precast concrete double wall (PCDW) system was developed to address the existing problems of RC structures and to improve the productivity of retaining wall construction. PCDW is a precast concrete (PC) wall in which two thin concrete panels are connected parallel to each other with truss-shaped reinforcement between them. PCDW can contribute to securing integrity, reducing the delay in construction, and improving quality. An overall process for the member design and construction stage of the PCDW system was proposed, and its improvement effects were examined regarding various aspects in comparison to the RC method.

Analisis Stabilitas Dinding Penahan Tipe Kantilever Pada Landfill Tepi TPA Kota Masohi Kabupaten Maluku Tengah Provinsi Maluku

The construction of a retaining wall must be based on a stability calculation and safety factors because errors that occur can be no good. A retaining wall construction can be said to be safe if it is fulfilled. The purpose of this study was to analyze the stability of cantilever type soil retaining walls against shifting, overturning, and soil bearing strength. overturning, and strongly supporting the soil. The method of collecting and collecting data in the field used the field observation method.Wall stability analysis using analytical Finite Element Method based software assistance. The results of data analysis show that the stability of the wall is safe against shear forces, rolling forces and the carrying capacity of the soil with a Safety Factor value of 4.05, 1.50, and 4.67.While the Out Put results from the application also show that the retaining wall at the Masohi City Landfill is still quite safe with a Safety Factor value of 1.80.

Physical Modeling of the Helical Anchor Walls’ Behavior Using Particle Image Velocity

Helical anchors are construction elements with a wide range of applications in geotechnical engineering such as excavation shoring, retaining wall construction, underpinning, seal wall construction, and foundation construction and reinforcement. In the present work, a laboratory model of a helical anchor wall is presented and evaluated. For this purpose, four types of anchors at three back slopes are designed in a sand soil and the effect of helical configuration (in terms of its diameter and number of helices) and back slope on wall crest displacement is investigated. Considering the laboratory scale of the designed model, the results obtained using the helical anchor were compared with laboratory results of soil nailing wall by applying the particle image velocimetry analyses. The results show that an increase in the back slope shows better the effect of the type of helical anchor and leads to a more efficient wall stabilization. As a result, in the case of surcharges, using a larger number of helical anchors and a higher number of helices would lead to better performance. In a wall with a 20° back slope, for example, an increase in the number of helices from 1 to 2 resulted in a 43% reduction in the displacement of wall crest. Besides, by changing the number of helices from 1 to 3, the displacement of wall crest was decreased by 62%. Since all anchors require a slight displacement rate to activate, in case the displacement required to activate the anchors exceeds the permissible displacement of the wall crest, it is recommended using a posttension helical anchor. Finally, it was found that the displacement of the wall’s crest in using the helical anchor method was much less than that of the nailed wall and the slip surface created in the helical anchor wall was parabolic.

Technical Guidance Note (Level 2, No. 18): Design of unreinforced masonry retaining walls

This Technical Guidance Note is intended to act as an aide to those seeking to design an unreinforced masonry retaining wall. Following this guidance will prevent cracking and ensure that the wall performs as originally intended. The note will not cover the design of reinforced masonry retaining walls and variants of that form. Such reinforcement typically strengthens the wall itself against induced bending stresses and the wall’s geometry will therefore be somewhat different to that of an unreinforced retaining wall. The note will also not discuss the applied actions that a retaining wall will be subjected to, nor the construction of retaining walls. These subjects have previously been covered in the following Technical Guidance Notes: Level 1, No. 8: Derivation of loading to retaining structures and Level 1, No. 33: Retaining wall construction. It is assumed that the reader is familiar with the content of both these notes.

Short-term flexural behaviour of concrete filled pultruded GFRP cellular and tubular sections with pin-eye connections for modular retaining wall construction

Abstract A retaining wall system modularly assembled from pultruded glass fibre reinforced polymer (GFRP) sections filled with concrete is introduced in this paper. Two main components (i.e., plank and pile) of the modular system are investigated experimentally at different spans under four-point bending to understand different failure modes. The effect of concrete filling, infill concrete modulus, and section shape (round and square), section size (300–600 mm) and spacing (0–600 mm) are studied through validated finite element modelling and results are compared with the existing reinforced concrete solution. Results show that the concrete filling increases the bending stiffness and prevents premature local crushing, tendency of ovalisation and local buckling by providing lateral supports to GFRP walls. Depending on pile spacing, the square pile deflects 7–13% less than the round pile with equivalent cross-sectional area. It has been found that the existing concrete pile may be replaced by a similar size of concrete filled GFRP pile for comparable performance in terms of stiffness.

Bio-Retaining wall as an adaptive design of constructed riverbank into sustainable urban riparian landscape management

Indonesia has been struggling in managing erosion and existed adjacent settlement in urban riparian landscape. Retaining wall construction has been done to handle the problems. It has protected the riverbank, but has not considered the ecological issues. Moreover, some of the existing retaining wall in Indonesian urban riparian has been built without any standard and proper management by the community who lives surrounding it, include in Ciliwung Riparian along Bogor City. The retaining wall may potentially risk and clearly not have any environmental benefit. This research was conducted to discover the design of retaining wall that has more adaptive to environment and household grey water biofiltering, called as Bio-Retaining Wall. The case study was carried out in Ciliwung Riparian along Bogor City. Research data such as Retaining Wall Information Collection and Assessment System (WICAS) and design processes by adaptive model approach were combined as the methods for generating design in this research. The assessment result showed that most of retaining walls in the riparian were in risky condition of erosion, landslide, and poor household drainage. Bio-Retaining Wall is designed as adaptive retaining wall by having particular components for wastewater separation, water filtration, and plant cultivation. Despite the fact that Bio-Retaining Wall need further development, it may have prospect for the future of constructed riverbank into more sustainable by considering ecological aspect.

Lock-brick System for Sustainable and Environment Infrastructure Building Materials

The community participation is expected to realize the appropriate housing. But the financial condition does not support, so that appropriate housing to be half constructed, which eventually became jammed unsustainable. Lock-brick system building construction can be implemented for appropriate housing and water infrastructure, such as small ponds and retaining wall construction. Lock-bricks are made from soil as the main ingredients added a little cement, thoroughly mixed in dry conditions, has dampened with water to a level sufficiently moist. Then, pressed with a pressing machine to 60%, forming interlocked bricks when arranged to form the walls of the liveable house. Columns, beams or retaining walls can be constructed with this system. Similarly, other water basin infrastructure such as rainwater catchers-canals can be constructed with this system. Lock-brick systems are used for a wide range of building infrastructure while considering the strength of the structure, so as to meet the standards. Various examples of usability have been done for the simple building liveable housing, student dormitories building, rain water reservoir, runoff catchment canals, soil retaining walls, and pavement floor. The usability, simple, easy to make and cheap, making this lock-brick system can support the development of sustainable infrastructure and built environment.

Model of Timber Crib Walls Using Counterweight in Bone Bolango Regency Gorontalo Province Indonesia

Crib wall is one type of retaining wall that is often done for slope reinforcement. Usually made of pre-cast concrete beams mounted interlocked-hooks with considerable construction costs. Based on that it is necessary to research the construction of slope reinforcement with low cost and easy in its implementation. The purpose of this research is to design crib wall by utilizing the local material. The research location is the slope of Trans Sulawesi-Pantai Selatan Street, precisely the slope of the road in Muara Bone Village (Bone Subdistrict) and Oluhuta Village (Kabila Bone Subdistrict), Bone Bolango Regency. Crib wall material used is timber obtained from around the research area. Slope stabilization analysis was performed using limit equilibrium with the help of Slide3 2017. The results of external and internal stability analysis showed that the slopes with the construction of timber crib walls in stable condition (Factor of Safety, FS>1.5). It is expected that the crib wall model can be an alternative to stabilize the roadside slopes in Bone Bolango District, due to the cheaper construction cost compared to other conventional retaining wall construction.

ANALISIS EFISIENSI DINDING PENAHAN TANAH TYPE KANTILEVER DI KECAMATAN BABAHROT KABUPATEN ACEH BARAT DAYA

The retaining wall is a retaining construction so that the soil does not slide. This construction is used for a cliff that is somewhat steep or erect, if without a retaining wall, the cliff will slide. Southwest Aceh Regency, especially in Babahrot-Blangkejeren road, Singgah Mata Mountains of Babahrot Subdistrict often experience landslide disaster. The cantilever type retaining wall is considered to be better against the structure and is suitable for use in mountain areas. However, a construction project generally requires substantial cost, therefore the selection of appropriate construction can provide efficiency to prevent loss and yields that are less than optimal. Based on that, it is necessary to analyze the cost estimation of retaining wall construction on mountain cliff, in this case using cantilever method. Functionally, the estimated cost is also intended for the calculation of the volume of work, the preparation of budget plans and scheduling in the implementation process of a construction project activity. This research was conducted to calculate dimension and cost estimation of cantilever type retaining wall construction with representation of segment that exist in surrounding mountain cliff of Babahrot-Blangkejeren road STA 13 + 850 - 13 + 895 Singgah Mata mountains at Babahrot Subdistrict, Southwest Aceh Regency. By obtaining wall dimension data from previous measurements and planning, this study analyzes and estimates the volume, cost, efficiency of the cantilever type retaining wall construction. From result of research indicate with planning, minimum safety factor required sf greater than 1,5, hence budget cost for cantilever type wall worth Rp. 1.109.438.000, -.

Modification of Reinforced Concrete Retaining Wall at Pilangbango Reservoir Construction Project Madiun, East Java

The reservoir is the tendon of water in order to accommodate the excess rain water in the rainy season and its utilization in the dry season for various purposes, both in the field of agriculture as well as the interests of the community. To find out the cause of the crack wall of the reservoir Pilangbango Madiun, East Java, then do the test strongly press on concrete walls and soil investigations on the area of the reservoir. Spunpile 400 mm in diameter used by the mounting distance 200 cm and a depth of 12 m and pole mounted on the heels of concrete walls. Manual calculation of the results and analysis of the Finite Element program it can be concluded that in the presence of an additional retaining her 400 spunpile mm using a distance 200 cm and a depth of 12 m, retaining wall construction is then quite able to hold style pillow case and Sliding with style has a safety factor more than 1.5. So the movement of the sliding walls do not happen again.