The “El Derby” reinforced soil wall

The improvement of transportation systems is extremely relevant in the development of a city and its life quality. The Lima municipal government aimed to recover the right-of-way of the main highways. Hence, an auxiliary road, occupied by the Peruvian “Jockey Club”, was used for the construction of the new “El Derby” road interchange.

During the peak-hour, the existing road interchange has 8% of the average total traffic volume. Moreover, the reduction in Level of Service is given by qualitative but not quantitative factors. Such qualitative factors are the lane reduction and high vehicle density in the entry/exit transverse intersection.

The proposed solution is using a combination of branches with grade separation which have high and constant service values for a traffic forecast of 10, 20 and 30 years. Similarly, the proposed road interchanges have no grading because space is a concern. Hence, the MacForce ® reinforced soil system was opted.

The MacForce ® mechanically stabilized earth wall has concrete segmental panels as façade and it is reinforced with polymer straps that render the structure stable. The finshing of the segmental panels can be either smooth or textured whereas the polymer straps are made out of multifilament high-tenacity polyester.

The FHWA-NHI-00-043 manual and the AASHTO design method were used to estimate the stability of the reinforced soil walls. The stability analysis for each cross-section were modelled using ADAMA’s MSEW v3.0 software. Given that the analysis were used based on the LRFD 2007-2010 guides, the stabilities were verified considering that the CDRs would be equal or larger than 1.00.