MYH12-Maths, physics, Engineering Tutor

For most of concrete mixes, over- vibration creates the problem of segregation in which the denser aggregates settle to the bottom while the lighter cement paste tends to move upwards. ... If concrete is placed in a single lift for road works, the resistance to abrasion is poor for the laitance surface of the carriageway.

EFFECT OF OVER VIBRATION

Steps Involved In Concreting Process Concrete is a construction material made from a mixture of cement, aggregate (sand or gravel), water and sometimes admixtures in required proportions. Following are the major steps which involved in concreting process: Steps In Concreting: Batching: The process of measuring different concrete materials such as cement, coarse aggregate, sand, water for the making of concrete is known as batching. Batching can be done in two different ways. 1. Volume Batching 2. Weight Batching. In volume batching the measurements of concrete materials are taken by volume & On the other hand the measurements are taken by weight in weight batching. Mixing: In this process, all the materials are thoroughly mixed in required proportions until the paste shows uniform color and consistency. Hand mixing and machine mixing are the two different methods of mixing. Note: To achieve optimum quality the materials should be mixed first in dry condition and then in wet condition. Transportation: When the mixing is done properly the freshly made concrete is then transported to the construction site, this process is known as transportation. After that, the concrete is correctly placed on the formworks. Concrete can be transported to the site location in two ways 1. Manual Transportation. 2. Mechanical Transportation. Compaction: Compaction is the process in which the air bubbles are eliminated from the freshly placed concrete. It is required to increase the ultimate strength of concrete by enhancing the bond with reinforcement. Curing: Curing is the process in which the concrete keeps its moisture for a certain time period to complete the hydration process. Curing should be done properly to increase the strength of concrete.

A lintel or lintol is a structural horizontal block that spans the space or opening between two vertical supports. It can be a decorative architectural element, or a combined ornamented structural item. It is often found over portals , doors , windows and fireplaces. In the case of windows, the bottom span is instead referred to as a sill , but, unlike a lintel, does not serve to bear a load to ensure the integrity of the wall. Modern day lintels are made using prestressed concrete and are also referred to as beams in beam and block slabs or ribs in rib and block slabs. These prestressed concrete lintels and blocks are components that are packed together and propped to form a suspended floor concrete slab.

pothesized structural relationship between one construct and another. This shows the cause and effect relationship. Each hypothesized relationship uses one degree of freedom. The model can be recursive or non-recursive. Examine the structural model validity: In the last step, a researcher examines the structural model validity. A model is considered a good fit if the value of the chi-square test is insignificant, and at least one incremental fit index (like CFI, GFI, TLI, AGFI, etc.) and one badness of fit index (like RMR, RMSEA, SRMR, etc.) meet the predetermined criteria.