Journal of Civil Engineering and Structures

Study of Pre-stressed Concrete Beam under Flexural Loading

2025-01-20T14:05:19+00:00

Today, saving energy in various fields has a special importance. Given the progresses made in the civil engineering, it can be mentioned in the optimal design of structures with the aim of using the minimum of material and human resources to achieve a maximum capacity of the structure. We can achieve more economic and even more beautiful design with designing and assigning the cross-section of the bridge as a changeable form due to the long length of some concrete bridge spans and thus the great number of changes in the internal forces of the cross-section. In this paper, pre-stressed transverse beams are modeled and optimized based on the principles and relations of the finite components. In this purpose, by using the results of a laboratory research, the mentioned beam is modeled in ABAQUS software and load variable in different beam is considered. For this aim, evaluate the effect of changing load of the tendons in the concrete beams performance and compared Pre-stressed concrete with normal concrete.

A method to couple bond-based peridynamic theory and displacement extrapolation method for calculation of stress intensity factor in isotropic plates with crack and hole

2025-01-19T09:37:12+00:00

This paper introduces a new approach to calculate stress intensity factors based on a combination of ordinary bond-based Peridynamic Theory and Displacement Extrapolation Method (DEM). To demonstrate the capability of the proposed approach, different benchmark problems are considered including plate with a central crack, plate with two offset edge crack and plate with crack and hole. Good agreements between proposed method and reference solutions indicate the high performance and capability of the proposed method in calculating the stress intensity factor in plates with discontinuities. It can also be stated that the stress intensity factor in isotropic plates with crack and hole depends on the length of the crack and hole radius and their location and number, and by changing these factors, the stress intensity factor in the body will also change.

Strength and durability studies on self-curing concrete with bethamcherla stone waste under sulfuric acid attack

2025-01-19T09:37:20+00:00

Concrete is a frequently utilized building material because it is affordable and strong Concrete is ranked second after water due to its widespread use The most widely used building material is concrete, which is also the second most consumed substance globally Aggregates add a major volume to concrete. The aggregates comprise around 70-80% of the volume of the structural concrete, with coarse aggregate (CA) accounting for 40-50% and fine aggregate for 25-30%. Bethamcherla stone at 0%, 10%, 20%, 30%, 40%, and 50% by weight of coarse aggregate is used as coarse aggregate allows us to create a combination that is as economical as possible. Concrete can self-cure by adding polyvinyl alcohol at concentrations of 0.03%, 0.06%, 0.12%, and 0.24%.

Crack propagation modeling in two-dimensional isotropic plate using bond-based peridynamic theory‏

2025-01-20T10:15:09+00:00

Many problems of solids mechanics involve discontinuities in the body geometry or displacement field. A common example of these problems is the presence of cracks in the body. Analysis and modeling of the crack growth in bodies and structures is one of the important issues for designing methods to prevent crack growth or stop it and prevent sudden failure, thus increasing the lifetime of structures. Extensive research has been conducted to model the crack growth and failure in bodies. Despite the suggestion of various analytical and numerical methods to predict the path of crack growth in bodies, there are still many problems in modeling the crack growth and failure in bodies with single points and discontinuities. In recent years, a new theory called peridynamic theory has been proposed to model and analyze such problems. The formulation framework of the peridynamic theory is based on integral equations. Also, single points, discontinuities, and damage in the body and their modeling are another type of deformation and part of the structural equations of this theory. So, peridynamic theory can be used directly, without the need for additional relations, to model crack growth in problems with single points and discontinuities. In the present study, the dynamic crack growth was modeled and the factors affecting crack growth and branching in bodies were investigated using the peridynamic theory in LAMMPS software. Then, the results of this study were validated with those of others. The comparison of the obtained results shows that the peridynamic theory is well able to model the crack growth in structures and bodies in different complex states, without the need for changing the criteria. Also, how the crack grows and branches in the body depends on the stress applied to the body and the number of initial pre-cracks and the location and arrangement of them in the body.

Laboratory study on the effect of rough bed in the stilling basin hydraulic jump characteristics

2025-01-21T10:38:34+00:00

One of the most important phenomena in hydraulic quick variable flow hydraulic jump in which the damage high energy, flow rate significantly decreases. In this study the effect of roughness and slope angle characteristics of hydraulic jump in spillway stilling basin has been investigated experimentally. For this purpose, 200 experiments land on the slopes numbers in the range of 1:1, 1:2 and 1:3 and roughness of 11, 18 and 22 mm were used. Laboratory results showed that Froude numbers tested by reducing the amount of energy loss is higher tilt angle overflow. Compare the results on rough and smooth overflow with bed showed that the secondary depth, Froude number, hydraulic jump over the rough bed significantly reduced energy loss. Laboratory results of the present study compared with previous studies a good agreement for energy dissipation of hydraulic jump in a stilling basin is rough substrates. Finally relationships to get married depth relative energy loss in supercritical Froude number input was provided for jerks formed on the substrate roughness.