This research presents experimental and theoretical investigation of 15 reinforced concrete spliced and nonspliced girder models. Splices of hooked dowels and cast in place joints, with or without strengthening steel plates were used. Post-tensioning had been used to enhance the splice strength for some spliced girders. The ANSYS computer program was used for analyzing the spliced and non-spliced girders. A nonlinear three dimensional element was used to represent all test girders. The experimental results have shown that for a single span girder using steel plate connectors in the splice zone has given a sufficient continuity to resist flexural stresses in this region. The experimental results have shown that the deflection of hooked dowels spliced girders is greater than that of non-spliced girder in the range of (17%-50%) at about 50% of the ultimate load which approximately corresponds to the serviceability limit state and the ultimate loads is less than that of non-spliced girder in the range of (12%-52%). For other spliced girders having strengthening steel plates at splices, the results have shown that the deflection of the spliced girder is less than that of non-spliced girder in the range of (2%-20%) at about 50% of the ultimate load and the ultimate loads for spliced girder is greater than that of nonspliced girder in the range of (1%-7%). The post-tensioned concrete girders have shown a reduction in deflection in the range of (26% - 43%) at a load of 50% of the ultimate load as compared with that of ordinary girders. Moreover, post-tensioning increases the ultimate loads in the range of (70% - 132%). The results obtained by using the finite element solution showed a good agreement with experimental results. The maximum difference between the experimental and theoretical ultimate loads for girders was in the range of (3-11%).
This study investigated the shear performance of concrete beams with GFRP stirrups vs. traditional steel stirrups. Longitudinal glass fiber‐reinforced polymer (GFRP) bars were used to doubly reinforce the tested beams at both the top and bottom of their cross sections. To accomplish this, several stirrup spacings were provided. Eight beam specimens, measuring 300 × 250 × 2400 mm, were used in an experimental program to test under a two‐point concentrated load with an equal span‐to‐depth ratio until failure. Four beams in Group I have standard mild steel stirrups of 8 mm diameter, while four beams in Group II have GFRP stirrups with the same adopted diameter. The difference betwe
Quite anumber of parents and educators of this behavior,which is characterized by exaggerating locomotor activity and impulsivity and recklessness and the difficulty of continuing the status of certain bodily more than one minute ,and the difficulty of waiting to meet aparticular need or desire,it also characterized by thos meddling children the affairs of others and increased their chatter does not seem the case when you listen to talk to them and they characterized by weak self-confidence and are more solid and seem un able to keep ther responses because of the severity of anxiety .The research aims to know impulsive behavior among kindergartens children and its relation ship with some variables, and the sa
... Show MoreThrust blocks and restraint joints are the two most popular methods of counteracting the thrust force that generated at pipe fittings (bends, Tee, wye, reducers, dead ends, etc…). Both systems perform the same function, which is to prevent the joints from separating from the pipes. The aim of the study is to review previous studies and scientific theories related to the study and design of thrust blocks and restraint joints to study the behavior of both systems under thrust force and to study the factors and variables that affect the behavior of these systems. The behavior of both systems must be studied because they cannot be abandoned, as each system has conditions whose use is more feasible, scientific, and economic
... Show MoreThis investigation integrates experimental and numerical approaches to study a novel solar air heater aimed at achieving an efficient design for a solar collector suitable for drying applications under the meteorological conditions of Iraq. The importance of this investigation stems from the lack of optimal exploitation of solar energy reaching the solar collector, primarily attributable to elevated thermal losses despite numerous designs employed in such solar systems. Consequently, enhancing the thermal performance of solar collectors, particularly those employed in crop drying applications, stands as a crucial focal point for researchers within this domain. Two identical double-pass solar air heaters were designed and constructed for
... Show MoreModern asphalt technology has adopted nanomaterials as an alternative option to assert that asphalt pavement can survive harsh climates and repeated heavy axle loading during service life and prolong pavement life. This work aims to elucidate the behavior of the modified asphalt mixture fracture model and assess the fatigue and Rutting performance of Hot Mix Asphalt (HMA) mixes using the outcomes of indirect Tensile Strength (IDT), Semicircular bend (SCB) and rutting resistance; for this, a single PG (64−16) nanomodified asphalt binder with 5 % SiO2 and TiO2 have been investigated through a series of laboratory tests, including: Resilient modulus, Creep compliance, and tensile strength, SCB, and Flow Number (FN) to study their potential
... Show MoreThe performance of composite prestressed concrete beam topped with reinforced concrete flange structures in fire depends upon several factors, including the change in properties of the two different materials due to fire exposure and temperature distribution within the composition of the composite members of the structure. The present experimental work included casting of 12 identical simply supported prestressed concrete beams grouped into 3 categories, depending on the strength of the top reinforced concrete deck slab (20, 30, and 40 MPa). They were connected together by using shear connector reinforcements. To simulate the real practical fire disasters, 3 composite prestressed concrete beams from each group were exposed to high t
... Show MoreThere are many different methods for analysis of two-way reinforced concrete slabs. The most efficient methods depend on using certain factors given in different codes of reinforced concrete design. The other ways of analysis of two-way slabs are the direct design method and the equivalent frame method. But these methods usually need a long time for analysis of the slabs.
In this paper, a new simple method has been developed to analyze the two-way slabs by using simple empirical formulae, and the results of final analysis of some examples have been compared with other different methods given in different codes of practice.
The comparison proof that this simple proposed method gives good results and it can be used in analy
... Show MoreThis research investigated the influence of water-absorbent polymer balls (WAPB) on reinforced concrete beams’ structural behavior experimentally. Four self-compacted reinforced concrete beams of identical geometric layouts 150 mm × 200 mm × 1,500 mm, reinforcement details, and compressive strength