Optimizing the ultimate strength of precast reinforced concrete pipes in three‐edge bearing tests

Abstract

By utilizing Taguchi method, this paper presents a simplified approach that aims at developing technical recommendations of control factors of reinforcement and concrete for steel wire reinforced concrete pipes (SWRCP). For this purpose, the structural behaviors of full scale of 400 and 600 mm inside diameter SWRCPs were analyzed. Three control factors, namely wire diameter (dw), wire winding pitch (pw), and water/cement ratio of concrete (w/c of concrete) were designed in an L9 orthogonal array. The best possible levels were determined for maximization of crushing load (Fcr) and ultimate load (Fu) in three‐edge bearing tests and minimization of crack width (Wcr). Based on the results, the economical and optimal control factors of dw, pw, and w/c of concrete for SWRCPs with inside diameter of 400 mm are 6.5 mm, 100 mm, and 33.5%, respectively. For SWRCPs with inside diameter of 600 mm, the optimal control factors of dw, pw, and w/c of concrete are 6.5 mm, 33 mm, and 33.5%, respectively. In addition, by the use of analysis of variance, the contribution percentages of control factors were obtained and were used as the most effective factors on the Fcr, Fu, and Wcr for SWRCPs. Through the implementation of the study, this paper concludes a practical and significant overall idea of designing SWRCPs for pipe manufacturing industry.

Mechanical responses of bell‐and‐spigot joints in buried prestressed concrete cylinder pipe under coupled service and surcharge loads

“…The contact between the outer surface of rubber gasket and bell ring, between end faces of PCCP joints, and between PCCP and soil are all defined using the surface-to-surface contact approach, which can be described as a "hard contact" with a penalty condition to allow stress transmission between different surfaces. [32][33][34] The material parameters of PCCP and soil in the model are shown in Table 2 and Table 3, respectively.…”

Calibration of the descent local search algorithm parameters using orthogonal arrays

“…In order to introduce non-experienced engineers and practitioners to the design of orthogonal experiments, in the 60's, Genichi Taguchi [38] developed a set of tables designed to define the minimal set of experiments that provides statistically significant information about the problem. In engineering, this technique has been widely applied (see for example [39][40][41][42][43]).…”