Influence of Using Tire-Derived Aggregate on the Structural Performance of Buried Concrete Pipe under Embankment Load

Abstract

Induced trench method is a well-known technique usually used to reduce the soil pressure applied on buried pipes. This method involves the use of a lightweight compressible material above the buried pipe to increase the positive arching, and thus, to decrease the soil pressure applied on the buried pipe. However, little efforts have been given by previous studies to check the applicability of using tire-derived aggregate (TDA) as the light weight and compressible material in the induced trench method, where it is not clear if the TDA could be used to increase the positive arching for the case of concrete pipes with different diameters and backfill heights. Thus, this paper investigates the effect of using TDA on the structural performance of buried concrete pipes subjected to soil load using a validated three-dimensional finite element model. A sensitivity analysis has been carried out to examine the effect of the configuration of the TDA, backfill height, and pipe diameter on the performance of the TDA in reducing the pipe wall bending moment. It was found that increasing the backfill height decreases the performance of the TDA. Furthermore, increasing the pipe diameter up to 1.2 m increases the TDA performance. However, the performance of the TDA significantly reduces as the diameter increases from 1.2 m to 2.4 m. In addition, it was also observed that the TDA configuration has a remarkable influence on its performance, where it is necessary to place the TDA layer on top of the pipe crown to increase the positive arching. The results reported in this paper provide useful addition to the literature and will help designers to ensure the economic design of buried pipes using recyclable materials.

Sustainable Use of Tire-Derived Aggregate in the Protection of Buried Concrete Pipes under Combined Soil and Traffic Loads

“…In addition, the TDA used in this research is classified as Type A TDA in accordance with ASTM D6270-08 [9] as stated by Mahgoub [31]. Furthermore, the unit weight, modulus of elasticity, and Poisson's ratio of the concrete have been set equal to 24 kN/m 3 , 24,000 MPa, and 0.2, respectively, in accordance with many previous studies, e.g., [12,18,22,25].…”

“…In addition, the Mohr-Coulomb model has been used to simulate the behavior of the interface elements between the soil and the pipe. Furthermore, the behavior of the pipe has been modeled using the linear elastic model, similar to many previous studies, e.g., [12,18,22,25]. This is considered an important step in the methodology, particularly in the pipe design, because the crack development in the concrete pipes is related to the induced bending moment in the pipe wall.…”

“…As a result, TDA is being used successfully in buried pipe and culvert applications to reduce soil pressures imposed on buried structures by simply placing a TDA layer over the pipe to promote positive arching action [11]. Thus, the soil above the buried pipe settles further than the neighboring soil, and in this way, a positive soil arching mechanism is achieved [12]. Furthermore, because shear resistance through the soil sides cancels out the soil weight, the earth pressures above the pipe are less than the theoretical value of the soil weight on the pipe crown.…”

“…Additionally, the TDA was found to be effective in decreasing the bending moment, of which is a result of the seismic effects, with a percentage reduction range of 22 to 38%. Alzabeebee et al [12] examined the performance of the TDA in reducing the bending moment of concrete pipes subjected to embankment load (i.e., soil weight only) using three-dimensional finite element analysis. The effects of the pipe diameter and burial depth were considered in the study by Alzabeebee et al [12], where it was found that the efficiency of the TDA decreased as the burial depth increased.…”

Research on the interaction between trench material and pipeline under fault displacement

“…Cheng et al 13,14 analyzed the pipe-soil interaction and discussed the pipeline failure modes and the protective effect of the soil by established a 3D FE model. Saif et al [15][16][17][18] studied the influence of using different low stiffness materials, such as the Tire-Derived Aggregate (TDA), as trench fillings for buried pipes under different loads and conditions. These studies suggest that TDA can be an effective material for reducing stress and strain on buried concrete pipes, particularly in areas with seismic activity.…”