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A sandwich composite comprising ferrocement skins was developed as the primary structural module for building construction with indigenous materials. The indigenous reinforcement systems selected for use in ferrocement skins were jute burlap and chicken mesh (flexible galvanized steel wire). These reinforcement systems were characterized through performance of tension tests. The tensile strength, stiffness and ductility of jute burlaps were found to compare favorably with those of chicken mesh which is a viable reinforcement for use in ferrocement. Tension tests on ferrocement sheets indicated that indigenous reinforcement ratios above a threshold level could induce multiple cracking and strain-hardening behavior, producing a desired balance of tensile strength and ductility. The tensile strength of indigenous ferrocements with jute burlap reinforcement exceeded the theoretically predicted values, which could be attributed to the favorable interactions of the burlap reinforcement with the inorganic matrix, and the strengthening effects of hydrates precipitating within the yarn voids in burlap. Experiments were conducted to determine the bond strength and the required development length of the indigenous reinforcement in cementitious matrix. Indigenous sandwich composites comprising ferrocement skins with jute burlap reinforcement and an aerated concrete core made of lime-gypsum matrix and saponin foaming agent were fabricated and subjected to flexure testing. The sandwich composite provided relatively high flexural strengths; the flexural failure modes indicated that the relatively dense aerated concrete core makes important contributions to the flexural performance of the sandwich composite.

The use of brakes or energy dissipaters in the anchorages of rockfall barriers is based on their great slip resistance capacity. The brake energy dissipaters can dissipate the kinetic energy produced by the impact of rocks, which is transmitted to them through the system made up of a network of wires, poles, guided cables and anchorages. The dissipaters transform kinetic energy into heat through their deformation (strain), thus increasing the dynamic performance of the screens against falling rocks. These dissipating elements consist of two tubular steel loops (bearing ropes, ties) joined by two aluminium compression sleeves at its extremities, which are under pressure depending on the slip resistance that is desired. In this work a comparative analysis of results obtained from two tensile tests is carried out simulating the slip of the brake energy dissipaters when they are working. The first tests were carried out with a static tensile load. These tests were conducted on a bench with a hydraulic jack varying the tightening pressure on the dissipater's compression sleeves. The second test was the nonlinear dynamic simulation of symmetrical tensile tests and fixed point of the brake energy dissipater. This simulation was performed using the explicit finite element method (FEM), varying the coefficients of friction and speed of slippage between the bearing ropes. The numerical results of these studies show the correlation between the dissipation energy in the tensile tests and the fixed point between the two experiments. In addition, some complementary improvements with respect to the location and geometry of the design of these brake energy dissipaters are made by correcting the efficiency of brake energy dissipater and anchorage set of the rockfall barriers.

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