A comparison of flexural strengths of polymer (SBR and PVA) modified, roller compacted concrete
This brief article aims to reveal the flexural performance, including the equivalent flexural strength of PVA (Polyvinyl Alcohol) modified concrete by comparing it primarily with that of SBR (Styrene Butadiene Rubber) concrete. This data article is directly related to Karadelis and Lin [6].
Roller compacted sheets of polymer modified mortar
Abstract The strength development of a polymer modified mortar (PM mortar) compacted by rolling into sheets has been investigated and the test results include modulus of rupture, compressive strength and also bond strength when rolled onto a concrete surface at ages from 3 to 120 days. The mortar contained Ordinary Portland Cement (OPC), Pulverized Fuel Ash (PFA), fine sand, Polyvinyl Alcohol (PVA), and sometimes in addition Styrene Butadiene (SB) latex and silica fume slurry. As expected a mechanical roller provided the highest strengths with MOR values up to 26 MPa compared with up to almost 17 MPa for hand rolling. The forms of failure for cube specimens tested either parallel to or perpendicular to the as-rolled direction were the same; thus the adhesion between the layers was very good. The bond strength development for the PM mortar to concrete correlated well with the cube strength development. The highest bond strength of about 12 MPa was obtained with 8% PVA by weight of cement. However, inclusion of between 5–10% PVA by weight of cement only had a small effect on the bond strength between PM mortar and steel. The average bond strength value from Pull Out tests for plain steel bars was of the order of 5 MPa. The high bond strength to concrete as well as the high tensile strength shows that the PM mortar is especially suitable for enhancing the strength of concrete members in a repair situation, particularly in the form of ferrocement in which reinforcement is sandwiched between adjacent sheets of PM mortar.
Evaluation of buckling load and dynamic performance of steel shear wall retrofitted with strips made of shape memory alloy
One of the most imperfections of the steel shear wall is out of plane displacements that cause severe damage in both structural and non-structural elements. In this paper, the effects of shape-memory alloys on steel shear walls are investigated. First, a numerical analysis using the finite element method in ABAQUS software has been carried out according to an experimental test. The results of the numerical analysis have been verified with experimental results. Next, shape-memory alloy fibers have been added vertically and horizontally to various parts of the steel shear wall. The results show that retrofitting with the shape-memory alloy reduces the out-of-plane displacement of the steel shear wall under both cyclic and seismic loadings. Besides, the buckling load in the steel shear wall increases when it is retrofitted with the shape-memory alloy. Also, the total out-of-plane movement (accumulated absolute displacements) of the steel shear wall and non-structural damage are controlled by the characteristic of a shape-memory alloy material called “super-elastic”.