by crossriverwatch admin
Criticisms have continued to trail the recent recommendation of the House of Representative Ad hoc committee on composition and pigmentation of cement which reportedly overlooked the preponderance of submissions from majority stakeholders but acceded to a minority proposition that the “42.5mpa cement grade should be the minimum standard for construction works because it is less susceptible to misapplication”.
Faulting the committee’s report, a civil engineering consultant and lecturer with the Cross River State University of Technology CRUTECH, Engineer Joseph Ukpata said “It is not proper to make a general statement that a particular grade of cement be used for construction purposes. There are different kinds of construction. Is it when we are doing mass concrete for floors, or when we are doing plastering? Is it when we are doing blocks? It is not proper, the argument that a particular cement grade is susceptible to misapplications because in the same way you will misapply grade 32.5, you can misapply grade 42.5 and even 52.5.
“Misapplication is if you are supposed to put a quantity of cement for a particular grade of concrete and you as a contractor try to cut corners by putting less quantity of cement that is the misapplication of cement they are talking about and that is the most common misapplication of cement. So if you don’t put the right quantity of cement, the same effect you will have in the concrete is what you will have whatever the grade of cement is.”
The University don argued that they should be room for all grades of cement, just like we have in concrete; “we have grade 20 concrete, grade 25 concrete and so on. It all depends on the design specifications. The committee statement is too open and too general.”
According to him “the key point is this; are you saying if you have a concrete design specification which demands six bags of cement and you go and use three bags of cement being a 42.5 grade then it will not fail? It will still fail the concrete level because you have misapplied. Aggregates play very high role in concrete strength more than cement. If your aggregates are not good enough, no matter the cement strength the concrete will fail. By aggregates I mean the sand quality, stones etc. these aggregates takes about 70% of concrete.’
“In my common design for a storey building I prefer to use between 20 to 25 mpa concrete strength. Using anything above 25 mpa is not being realistic at all because you sit down to do a design and most often they take materials to site to mix and hardly can anyone achieve a concrete strength above 25mpa from that site.”
Engr. Ukpata however agreed with the aspect of the committee’s recommendation which called for the passage of the National Building Code Bill and strict enforcement to check quackery.
Defending the committee’s recommendation, a member of the Ad Hoc Committee, Hon. Essien Ekpeyong Ayi, representing Akpabuyo, Bakassi and Calabar South Federal constituency told our reporter that the committee has not put a dead nail on the manufacturing of 32.5 cement grade but after due consideration, they are saying that if 42.5 should be the common standard, then a reasonable time be given for manufacturing companies to retool and upgrade their production lines to start producing 42.5mpa cement grade.
He also noted that Standards Organization of Nigeria, (SON) governing council was not properly constituted as at the time they purportedly took a recent decision leading to the new Industrial Standard on cement which is why the committee recommended that the Governing Council of Standards Organization of Nigeria (SON) be properly constituted in line with Section 3(2) of the Standards Organization of Nigeria ACT and in strict compliance with Section 12 of the SON ACT.
It will be recalled that in his submission to the committee, the President of the Council for the Regulation of Engineering in Nigeria (COREN), Engr. Kashim A. Ali pointed out that building collapse in Nigeria has mostly involved storey buildings with hardly anything heard about bungalows which shows that Sandcrete blocks currently produced with both types of cements (32.5mpa & 42.5mpa) do not seem to have problems. It is when concrete is involved that we have problems and when it comes to concrete production, the blame cannot be put solely on the quality of cement.
“Moreso, there is no substandard cement in Nigeria unless we are not to believe SON’s statement that has continuously ensured that the adopted standards are strictly adhered to by all manufacturers.”
President of Nigeria Society of Engineers NSE, Engr. Ademola Isaac Olorunfemi had in his submission also before the House committee, advised that the production and marketing of Grade 32.5 Cement, grade 42.5 and grade 52.5 already certified and approved by the Standards Organization of Nigeria for use in Nigeria should continue unabated.
He emphasized that cement grade is not the cause of incessant collapse of buildings in Nigeria as erroneously propagated in some quarters. Adding, “with incontrovertible facts, it is our considered opinion that it is not correct to assert or affirm that a particular grade of cement is best for construction works.”
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