In more competent foundation profiles, mse walls can be used as direct support of bridge abutments. Presto offers its free, easytouse geoweb mse design software for retaining wall applications. If a txdot retaining wall standard is used for the wall design, it is the designers responsibility to. It may require additional reinforcement length to meet design. The retaining wall toe prevents the gabion wall sliding forwards, the depth of the toe needs to increase as the wall gets bigger. The i25i70 mse iff wall system functioned to a large degree almost as planned in the design. This data base of 171 failed mechanically stabilized earth mse walls with geosynthetic reinforcement includes 44 cases of excessive deformation and 127 cases of collapse of at least part of the wall. Zornberg4 abstract the design methodology for earth retaining structures placed in front of a stable slope or wall with limited space is unclear at present. Earth pressures and design considerations of narrow mse walls ken t. Ensure the last lift of backfill is sloped away from the wall facing at the end of each days operation.
Mechanically stabilized earth mse or reinforced soil is soil constructed with artificial reinforcing. Mse wall failures visavis the lack of filtration design. In spite of the increased usage, txdot has had relatively few retaining wall failures. Mse wall design spreadsheet introduction the intent of this document is to briefly describe mechanically stabilized earth wall mse wall technology and to describedefine the methodology, equations and input used for the mse wall design spreadsheet. It is recommended that users of this tek consult local building codes to determine additional srw requirements and the engineering needs of their project.
Internal design of mechanically stabilized earth mse retaining walls using crimped bars by bernardo a. Compared to existing mse design software options, vespa increases design efficiency, improves accuracy, and promotes a seamless flow of information between design stages and parties. Gec 11 design and construction of mechanically stabilized. Ensure soil layers do not exceed 12 inches according to the special provision for mechanically stabilized earth retaining wall system. Modifications to the wall design to avoid obstructions must be shown in the mse wall working drawings. A data base, statistics and recommendations regarding 171. Castellanos, master of science utah state university, 2010 major professor. Design considerations for mse retaining walls constructed in confined spaces 5. The mse wall design within this manual is based upon load and. Design method for the mse wall and rail supp or tsl ab is nc dew hlrfd g m.
That said, and with regard to mse walls, there are three distinct locations within the standard mse wall cross section that are deficient. Identify the four major components of a mse wall describe the basic construction sequence for mse. Design and construction of mechanically stabilized earth walls and reinforced soil slopes. Design options for obstructions within the reinforced zone are described in the aashto lrfd bridge design specifications, section 11.
Mse walls are structures comprised of steel or geosynthetic soil reinforcements connected to a. Since its appearance in 1970s, mechanically stabilized earth mse walls have. Design of mse walls for fully saturated conditions introduction over the past three decades, mechanically stabilized earth mse retaining walls have been increasingly used as design alternatives to traditional reinforced concrete retaining walls for supporting earth fills in civil infrastructure projects. The mechanically stabilized earth mse wall course provides an introductory lesson addressing the basics of mse wall design. Weldu submitted to the graduate degree program in the department of civil, environmental, and architectural engineering and the graduate faculty of the university of kansas in partial fulfillment of the requirements for the degree of master of science. Application areas nilexs retaining wall systems offer a variety of options for residential, commercial, industrial, highway, and rail applications all of which have unique features and advantages. The mse wall asset lends its self to ndt monitoring, condition assessment, in place repair. Design and performance of a 46mhigh mse wall article pdf available in journal of geotechnical and geoenvironmental engineering 66 june 2010 with 1,176 reads how we measure reads. Structural engineering continuing education for engineers. This system is recommended for all mse installations with expected differential settlements of 1100 or more and the total expected settlement is greater than three feet. Installation guideline strata geogrid mse wall from us fabrics.
Ss840 mechanically stabilized earth mse wallsbe advised ss840 dated 41920 is included in its entirety at the end of this document for reference only. The answer to each of these should be yes unless plans, specifications or specific approval has been given otherwise. Design and installation guidelines for retaining walls. Mechanically stabilized earth wall abutments for bridge. Spreadsheet design of mechanically stabilized earth walls. The wall system consists of the original ground, concrete leveling pad, wall facing panels, coping, soil reinforcement, select backfill and any loads and surcharges. Ensure soil layers do not exceed 12 inches according to the special provision for. Our dedicated mse division specializes in the delivery of mse systems of all types in all market segments. Txdot has designed and constructed numerous mse retaining walls. Regarding geotextile filtration design, our keyword literature search shows 107 papers are available. Soilstructure retaining wall software is an efficient and powerful program with the following unique capabilities. Accommodates wall movements that often occur when a heavy mse backfill structure is built on compressible foundation soils. The i25i70 mseiff wall system functioned to a large degree almost as planned in the design.
There are key mse wall design, material, inspection, and construction elements to consider. Course title construction of mechanically stabilized earth mse walls this training was developed by the transportation curriculum coordination council tccc in partnership with aashto and nhi. A wall of windows is a dramatic solution when youre trying to preserve a beautiful. Installation guideline for strata geogrid mse wall us fabrics. Part 1 history or mse structures ancient and modern. Successful wall construction requires a basic understanding of mse wall construction and carefully following the plans and specifications. When speed and aesthetics are the priority, ssls full height panel walls reduces installation time and are available in 5, 8, and 10 widths with variable heights up to 40 with.
Design engineer armtec drainage solutions andrew lister sales manager mirafi geosynthetics, tencate geotube friday april 22, 2016 9am pst 11am cst 12pm est technical. Rehabilitation of an existing mechanically stabilized earth. Nicholson construction company nicholson was selected as the designbuild geotechnical subcontractor to install the recommended permanent soil nails through the existing precast concrete panels of the mse wall. Nilex mse systems can be designed to address technical challenges such as potential for differential settlement and seismic activity, heavy loading and nonstandard backfill materials. Variations on the basic design, including curves, tiers, railings, stairs, walkways and the like are making them more and more attractive to designers and architects. For each of the mse wall alignments, the site and subsurface conditions should be analyzed to identify areas of geotechnical concern, risk, or potential variability in subsurface conditions which may influence the technical feasibility, design, andor construction or economic viability of the mse wall system. Mechanically stabilized earth mse retaining walls are growing in popularity. Specific design requirements for each of the wall types are discussed in the following sections o. A set of french doors with inset windows extends the view even farther.
Civil and environmental engineering current design codes of mechanically stabilized earth mse walls allow the use. Rail support slab collision tl4 design live loading. Gabion retaining wall design guidelines gabion1 usa. Design and construction of mechanically stabilized earth walls and reinforced soil slopes volume i and ii. The mse wall design within this manual is based upon load and resistance factor design lrfd procedures. When youve got a view of sandy beach and endless water, walling off a room seems like cruel selfdeprivation. Although the basic principles of mse have been used throughout history, mse was developed in its current form in the 1960s. Design manual mechanically stabilized earth mse chapter 200.
Indot check list for mse wall construction the following is a general checklist to follow when constructing a mechanically stabilized earth wall mse wall. Gec 11 design and construction of mechanically stabilized earth walls and reinforced soil slopes. Create vegetated and nonvegetated mse designs based on the geoweb system inputs for reinforced slopes, and for gravity and geogridreinforced walls. Mechanically stabilized earth structures amazon s3. Director of engineering armtec drainage solutions frank klita sales representative armtec drainage solutions michael mcquaid p. This training contains a collection of best practices from various agencies, including fhwa training rules, laws, policies, and procedures. Reliable wall system design see the building envelope design guide page on exterior walls generally includes a water resistant barrier behind the wall cladding, an air barrier, thermal insulation, and sometimes a vapor retarder. Pullout resistance of mse wall steel strip reinforcement in uniform aggregate by mehari t. Mse walls have been constructed in the state of ohio for over 25 years. Mechanically stabilized earth wall abutments for bridge support. Nicholson construction company nicholson was selected as the design build geotechnical subcontractor to install the recommended permanent soil nails through the existing precast concrete panels of the mse wall. A mechanically stabilized earth mse retaining wall is a composite structure consisting of alternating layers of compacted backfill and soil reinforcement elements, fixed to a wall facing.
The following are general design requirements for retaining walls that will be shown on the drawings or addressed in the contract documents. Mse wall connection design earth retention engineering. Managing the mse wall asset starts with the design cradle. It can be used for retaining walls, bridge abutments, seawalls, and dikes. Course title construction of mechanically stabilized earth. For more complex walls, stepbystep procedures are presented. Design considerations a gravity retaining wall must have sufficient weight and width or be otherwise supported so that it does not overturn or slide forward due to external forces being exerted upon it. Vespa mse retaining wall design software cti software.
C geosynthetic design and construction guidelines, by r. Download this handy guide for installing strata geogrids in retaining walls. Mse wall connection design panars geotechnical 18 oct 07 15. Rehabilitation of an existing mechanically stabilized. Mechanically stabilized earth mse wall inspectors handbook. When building gabions on softer soils, both the depth of the toe and the size of the base needs to be increased to spread the load over a wider area. Mseplus full height panel walls, and their virtually endless array of surface treatments provide a broader range of potential design effects in less time. A window wall gives any room the airy openness of a sunroom. For simple walls the design is facilitated by the use of design charts that were developed as part of this study and are presented in this report. The punched window openings in the wall system threaten to create holes in the waterairthermalvapor barriers. Unibear performs analysis based on working stress, limit states based on ohbdc 1991, load factor based on aashto 1992, and partial factor based on european codes. Installation guideline for strata geogrid mse wall us. Mse wall, precast panels typical section showing forces mechanically stabilized earth, geogrid facing height range h 5 to 50 ft 1.
The stability of the wall system is derived from the interaction between the backfill and soil reinforcements, involving friction and tension. Here are some inspired designs and updated looks for creating a room awash with windows. Pullout resistance of mse wall steel strip reinforcement. In previous years, there were special provisions in the contract that detailed the construction and design. Mse retaining wall design considerations by marcus galvan. How global stability analysis can help improve a mse walls design. Design manual mechanically stabilized earth mse chapter.
A dropped ceiling of sycamore panels and a fireplace wall of cementfiberboard paneling warm the metaledged windows, common in modern design. For the case examples analyzed in this study, the ratio of width over total height of the wall had to. Earth pressures and design considerations of narrow mse walls. The flexibility of the wall system accommodated the deformation of the reinforcement soil mass, especially those induced by heavy compaction, and allowed for mobilization of the tensile. Mse wall corrosion monitoring kit installation guide.
All of these items have an affect on the performance of the mse wall and are taken into account in the stability analysis. That said, and with regard to mse walls, there are three distinct locations within. Series 1 case 3 foundation cu2000 psf, backfill angle. This current report presents new guidelines for design of tiered mse walls. The design of a mse wall involves the following steps. The design and planning phase of retaining walls is critical and must address the actual site conditions, including soil and loading, that the wall will be subjected to. The course, which has been separated into three parts, covers the following topics. The wall must also be able to hold together as a unit in order to function. The load applied to the fascia should be applied through the window between the shafts assuming simple.
The large majority are located in north america and in the usa. Construction of mechanically stabilized earth mse walls. Floortoceiling windows flood this living room with light and afford lush views. Typical section 6 concrete crib wall typical section. Vespa allows the user to import grading and layout information directly from cad using a cad routine called awall that is included with the vespa software package. Mse wall is an intuitive program for mse wall design mechanically stabilized earth wall. The course materials present considerations for design and information contained in a geotechnical report. Design considerations and alternatives for retaining walls. Pullout resistance of mse wall steel strip reinforcement in. Performing organization name and address center for transportation research. You will receive free limited license of unibear 1. Course objectives they seem to crop up everywhere, like cell phone towers. This manual is a revision to lrfd and an update to the fhwa nhi00043 manual which was based upon allowable stress design asd procedures.