In this study, a stress-strain model of fiber-reinforced polymers (FRPs)-confined concrete based on the lateral confinement stiffness was adopted to simulate the lateral response of RC columns retrofitted with external FRP jackets and tested under axial and lateral loads. The adopted model and other five-stress-strain models (established in former studies) were comparatively studied to simulate the seismic response of eight RC-circular columns retrofitted with FRP jackets and experimentally tested under both axial and lateral loads. Compared to the experimental results, the simulation results indicated that all stress-strain models could not identify properly the ultimate lateral displacements of the simulated columns. The adopted stress-strain model was revised to consider the effect of a key influential parameter (eccentricity ratio), which showed a critical impact on the simulation of the seismic response of RC-columns under combined bending and axial loadings. Finally, the proposed model was evaluated in predicting the lateral response of additional three columns and the simulation results exhibited a good agreement with the experimental results.

Cooling of buildings is an essential target for engineers and builders in the hot arid climate of Egypt. Performance of inclined solar chimney with passive cooling tower (SCPC) was studied. The system was integrated into a single room built in Assiut University (El-Gorib site) in Assiut, Egypt. Testing of indoor environment for the room with passive cooling was done during August and September 2015. A passive cooling technique was integrated inside a short wind tower made from expanded paper (wet pad) 0.1 m thick. A water tube was installed on the top of the expanded paper with small nozzles. Water is recirculated through the system using water pump. A reduction of room indoor temperature was observed with the integrated system (SCPC). There is a significant reduction of indoor temperature between 6 and 7 K due to passive cooling with surface temperature 19.4 °C for the cooling pad. The relative humidity did not exceed 57% most of the time. The maximum air speed inside the solar chimney was 3.5 m/s under the effect of a high solar radiation of 890 W/m2. The findings show that SCPC system achieves comfortable thermal conditions with a significant improvement in building energy conservation. The result of development this new cooling system helps to develop building code for low energy houses in Egypt and propose a new system to be integrated in the housing project of people with low income.

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The design of segmental lining of TBM tunnels requires a special experience and knowledge. One of the influencing factors affecting the stresses induced in the lining, which is often ignored in the design of tunnels, is the effect of joint which connects each two segments, and known as the longitudinal joint, or the tunnel hinge. In this paper curves for the joint rotational stiffness under the effect of normal force and moment are presented based on a numerical modelling of tunnel hinge, considering the steel reinforcement of the segment, plasticity of concrete, decoupling and properties of segmental joints. The result obtained from the curves is directly coupled with the finite element program FINAL (Swoboda 2007), and hence it can be applied in the design of segmental lining. The numerical modelling of the tunnel hinge consists of two concrete parts represent the segments, the length of each concrete part equals its thickness, and the width of the hinge equals half of the thickness of the segment, the numerical model is based on LST elements for concrete considering a new explicit formulation of concrete plasticity, and the decoupling is simulated with an interface element. A program ‘Hinge’ was made depending on the results of the numerical modelling of tunnel hinge, this program can calculate the value of the rotation of the hinge as a function of the normal force and bending moment, also the program can expect the type of the deformation in the hinge however it is elastic or plastic, at the end of this paper there is an application on TBM tunnel by using the results of program Hinge.

The design of segmental lining of TBM tunnels requires a special experience and knowledge. One of the influencing factors affecting the stresses induced in the lining, which is often ignored in the design of tunnels, is the effect of joint which connects each two segments, and known as the longitudinal joint, or the tunnel hinge. In this paper curves for the joint rotational stiffness under the effect of normal force and moment are presented based on a numerical modelling of tunnel hinge, considering the steel reinforcement of the segment, plasticity of concrete, decoupling and properties of segmental joints. The result obtained from the curves is directly coupled with the finite element program FINAL (Swoboda 2007), and hence it can be applied in the design of segmental lining. The numerical modelling of the tunnel hinge consists of two concrete parts represent the segments, the length of each concrete part equals its thickness, and the width of the hinge equals half of the thickness of the segment, the numerical model is based on LST elements for concrete considering a new explicit formulation of concrete plasticity, and the decoupling is simulated with an interface element. A program ‘Hinge’ was made depending on the results of the numerical modelling of tunnel hinge, this program can calculate the value of the rotation of the hinge as a function of the normal force and bending moment, also the program can expect the type of the deformation in the hinge however it is elastic or plastic, at the end of this paper there is an application on TBM tunnel by using the results of program Hinge.

The design of segmental lining of TBM tunnels requires a special experience and knowledge. One of the influencing factors affecting the stresses induced in the lining, which is often ignored in the design of tunnels, is the effect of joint which connects each two segments, and known as the longitudinal joint, or the tunnel hinge. In this paper curves for the joint rotational stiffness under the effect of normal force and moment are presented based on a numerical modelling of tunnel hinge, considering the steel reinforcement of the segment, plasticity of concrete, decoupling and properties of segmental joints. The result obtained from the curves is directly coupled with the finite element program FINAL (Swoboda 2007), and hence it can be applied in the design of segmental lining. The numerical modelling of the tunnel hinge consists of two concrete parts represent the segments, the length of each concrete part equals its thickness, and the width of the hinge equals half of the thickness of the segment, the numerical model is based on LST elements for concrete considering a new explicit formulation of concrete plasticity, and the decoupling is simulated with an interface element. A program ‘Hinge’ was made depending on the results of the numerical modelling of tunnel hinge, this program can calculate the value of the rotation of the hinge as a function of the normal force and bending moment, also the program can expect the type of the deformation in the hinge however it is elastic or plastic, at the end of this paper there is an application on TBM tunnel by using the results of program Hinge.

A numerical study was carried out using the finite element analysis program FINAL to investigate the effect of joint attributes on the maximum bending moment induced in the segmental tunnel lining, the analysis has been performed with different combination of segments number, joint orientation, tunnel depth, and the ground coefficient at rest ko. The model used in the analysis was for a water tunnel exposed to an internal and external water pressure, The results show that, the orientation of hinges has a significant effect on the moment induced in the lining in case of number of segments equals four, and it has a maximum value if the angle between the vertical axis of tunnel and the first joint is 45o, in this case it is preferable to erect the segments by keeping the angle between the axis of the tunnel and the first joint not more than 20o for the economic design. Also the orientation of joints on the moment of the lining decreases when the number of segments is five, and it is nearly no effect for the orientation if the number of segments is seven, or more. The number of joints has a greater effect on the maximum bending moment induced in the lining, where as the number of segments increases the bending moment decreases. However, beyond a number of joints equals ten the increase of number of joints has a little influence on the values of stresses induced in the lining, and for the economical design, the number of segments is preferred to be more than four, and the most economical design can be obtained if the number of joints is seven. For the effect of ko on the moment induced in the lining it was found that, the moment is nearly zero if ko equals 1.0, however the value of moment increases in the both cases, if Ko increases or decreases than 1.0.