A number of geotechnical analyses were carried out on selected carbonate rock samples from eight sites located in Egypt. This analysis was to assess the suitability of these rocks for building construction aggregate. ...A number of geotechnical analyses were carried out on selected carbonate rock samples from eight sites located in Egypt. This analysis was to assess the suitability of these rocks for building construction aggregate. The analyses included properties of uniaxial compressive strength, tensile strength, porosity, water absorption, and dynamic fragmentation. The success of building construction depends to a large extent on the availability of raw materials at affordable prices. Raw materials commonly used in the building industry include sands, gravels, clays and clay-derived products. Despite the widespread occurrence of carbonate rocks throughout Egypt, the low premium placed on their direct application in the building sector may be explained in two ways: firstly, the lack of awareness of the potential uses of carbonate rocks in the building construction industry(beyond the production of asbestos, ceiling boards, roof sheets and Portland cement); and secondly, the aesthetic application of carbonate rocks in the building construction depends mainly on their physical attributes, a knowledge of which is generally restricted to within the confines of research laboratories and industries. Thus this paper addresses the physical and mechanical characteristics of some Egyptian carbonate rocks, evaluating them for their suitability as building construction aggregates.展开更多
Concrete, as an essential construction material in the construction industry, is the main component of solid waste. To improve the strength and durability of concrete, some additives can be added into concrete to repl...Concrete, as an essential construction material in the construction industry, is the main component of solid waste. To improve the strength and durability of concrete, some additives can be added into concrete to replace parts of cement. Carbon fiber and silica powder are the most common additives. Under a series of experiments, the effects of temperature, carbon fiber and silica powder on the mechanical properties of concrete were studied under normal circumstances. In this paper, a conclusion on the effects was drawn up mainly through some experimental analyses, so as to discuss the effect laws and provide a reference to manufacture the concrete of high strength and properties.展开更多
The paper summarises the results of a questionnaire survey that took place in January 2015 in order to assess the current and prospective standard of the qualification of human resources in machine construction compan...The paper summarises the results of a questionnaire survey that took place in January 2015 in order to assess the current and prospective standard of the qualification of human resources in machine construction companies in the Czech Republic. The questionnaire survey included 23 small machine construction companies （less than 50 employees）, 24 medium-sized machine construction companies （50-249 employees）, and 53 larger machine construction companies （250 and more employees）. The results of the survey indicated that almost one half （43%） of respondent machine construction company top management members planned to hire new employees this year. In addition, 50% of them confirmed their endeavour to keep the current headcount and a mere 7% of them specified problems that would lead to the dismissal of employees. However, what is bothering machine construction top management members is the lack of qualifications and practical experience of job seekers they have to deal with. The intention of the authors is to define the main reasons and propose possible solutions of this problem within human resource management in machine construction companies.展开更多
文摘A number of geotechnical analyses were carried out on selected carbonate rock samples from eight sites located in Egypt. This analysis was to assess the suitability of these rocks for building construction aggregate. The analyses included properties of uniaxial compressive strength, tensile strength, porosity, water absorption, and dynamic fragmentation. The success of building construction depends to a large extent on the availability of raw materials at affordable prices. Raw materials commonly used in the building industry include sands, gravels, clays and clay-derived products. Despite the widespread occurrence of carbonate rocks throughout Egypt, the low premium placed on their direct application in the building sector may be explained in two ways: firstly, the lack of awareness of the potential uses of carbonate rocks in the building construction industry(beyond the production of asbestos, ceiling boards, roof sheets and Portland cement); and secondly, the aesthetic application of carbonate rocks in the building construction depends mainly on their physical attributes, a knowledge of which is generally restricted to within the confines of research laboratories and industries. Thus this paper addresses the physical and mechanical characteristics of some Egyptian carbonate rocks, evaluating them for their suitability as building construction aggregates.
文摘Concrete, as an essential construction material in the construction industry, is the main component of solid waste. To improve the strength and durability of concrete, some additives can be added into concrete to replace parts of cement. Carbon fiber and silica powder are the most common additives. Under a series of experiments, the effects of temperature, carbon fiber and silica powder on the mechanical properties of concrete were studied under normal circumstances. In this paper, a conclusion on the effects was drawn up mainly through some experimental analyses, so as to discuss the effect laws and provide a reference to manufacture the concrete of high strength and properties.
文摘The paper summarises the results of a questionnaire survey that took place in January 2015 in order to assess the current and prospective standard of the qualification of human resources in machine construction companies in the Czech Republic. The questionnaire survey included 23 small machine construction companies （less than 50 employees）, 24 medium-sized machine construction companies （50-249 employees）, and 53 larger machine construction companies （250 and more employees）. The results of the survey indicated that almost one half （43%） of respondent machine construction company top management members planned to hire new employees this year. In addition, 50% of them confirmed their endeavour to keep the current headcount and a mere 7% of them specified problems that would lead to the dismissal of employees. However, what is bothering machine construction top management members is the lack of qualifications and practical experience of job seekers they have to deal with. The intention of the authors is to define the main reasons and propose possible solutions of this problem within human resource management in machine construction companies.
