MSEW+ is an interactive program for the design and analysis of mechanically stabilized earth walls. It follows the design guidelines of:
- AASHTO98 /Demo 82
- AASHTO 2007-2010
- FHWA-NHI-10-024 (as related to traffic barrier load and some of the bridge abutment methodology)
- AASHTO 2017-2020. Simplified AASHTO Method for geosynthetics and metallic reinforcement as well as an option for using Coherent Gravity Method for metallic.
- AASHTO 2020 – Simplified Stiffness Method for geosynthetics which can be used instead of the Simplified AASHTO.
- Note: An alternative method for designing geosynthetic walls allowed in AASHTO 2020 is based on limit equilibrium (LE). Its unique feature is its ability to rationally deal with internal stability. This LE has been implemented in program ReSSA+. Hence, the two programs MSEW+ and ReSSA+ complement each other.
AASHTO98/02 and NCMA are based on allowable stress design (ASD) whereas AASHTO 2007-2010 and 2017-2020 are based on load and resistance factors design (LRFD). NCMA is limited to geosynthetic reinforced segmental retaining walls (SRW). Although the program generally follows the guidelines of established design procedures, the user can explore design options and concepts beyond the formal guidelines; the user can override all default values including load and resistance factors. Such exploration is useful for the development of new systems as well as the occasional need to conduct forensic study. Some codes outside the US use different default values in design thus making MSEW+ acceptable design tool in these countries.
MSEW+ allows for global stability analysis using Bishop method with circular arc. For more in-depth and efficient global analysis, MSEW+ can export data files for analysis using ReSSA+. Such exported data files facilitate a more comprehensive stability analysis for which ReSSA+ is ideal. Furthermore, by a click of a button, virtually all tables in MSEW+ can be exported to Excel or be printed. Input data files generated using MSEW(3.0) can be read using MSEW+.
ADAMA Engineering developed the copyrighted program MSEW Version 1.0 (1998) for the US Federal Highway Administration (FHWA). Version 1.0 has been designated exclusively for use by US State Highway Agencies and by US Federal agencies. ADAMA Engineering offers MSEW+ to the public. This version includes many enhancements such as calculations of quantities, more versatile surcharge loads, use of Coulomb lateral earth pressures for both internal and external stability, user’s generated databases, improved presentation of slope stability results, graphic files compatible with AutoCAD®, design methods based on NCMA or LRFD, and more.
Several FHWA relevant publications are accessible from MSEW+. However, since AASHTO and NCMA publications are copyrighted, ADAMA Engineering cannot distribute these documents. It is recommended that users purchase a copy of AASHTO’s Bridge Section as well as NCMA 2nd edition. The technical background and details provided in these manuals is invaluable. Together with MSEW+, the user can quickly become knowledgeable with often convoluted design rules and calculations. ADAMA Engineering is providing MSEW+ solely as a tool; however, the user should be familiar with AASHTO and/or NCMA rules. ADAMA Engineering offers free support related to issues associated with running its software, not to the design rules and calculation prescribed by AASHTO/FHA/NCMA. However, it is noted that many of the dialogs in MSEW+ include sub-dialogs and buttons that attempt to clarify concepts, formulations, and source or rationale.