Engineers warn (again) that Route 27 poses danger to motorists

A landslide on Saturday caused the closure of Route 27.
(Photo courtesy of Wilberth Hernandez and CRHoy.com)

November 4^th, 2014 (InsideCostaRica.com) In a statement circulated to the press on Monday, engineers from the National Laboratory of Materials and Structural Models (LANAMME) of the University of Costa Rica (UCR) warn that the situation on Route 27 is “critical” and “represents a danger to road users.”

The statement, which comes after the most recent landslide on Route 27 which has closed a section of the roadway for the past three days, is at least the fifth such warning issued by LANAMME.

“We have repeatedly warned about the vulnerability of various points [on Route 27],” the statement said.

Engineers are especially concerned about several slopes that are covered with a material known as “Shotcrete,” a form of spray-on concrete.  LANAMME says that several such slopes suffer from “hydrothermal alteration” which has damaged the Shotcrete.  “The potential release of concrete represents a danger to road users,” according to LANAMME.

The statement said that deficiencies on the roadway have dragged on for years.

LANAMME said that the route requires urgent intervention by concessionaire, Globalvia, calling the situation “critical.”

Globalvia, for its part, has stated that the weekend landslide was caused by recent heavy rains and a moderate earthquake that shook the Central Valley over the weekend and that it conducts “regular maintenance” on the highway and the slopes surrounding it.

An April report by LANAMME warned that at least six slopes on the highway posed risk of collapse or landslide.

The April study found that between kilometers 37 and 48, several of the hillside slopes covered with spray-on concrete that tower over passing motorists are damaged and could fail.  Some 16,000 vehicles pass through the area each day.

Cracks in the concrete covering of the slopes have resulted in the installation of meshing in some areas to prevent against falling material.  Areas of missing concrete show orange staining from rusting rebar in some sections.

Route 27 between the Orotina and Atenas interchanges (kilometer 40) remained closed Tuesday morning.