Needle Penetration Test Lab Report
3. LABORATORY TESTS USED TO STUDY THE STRENGTH OF CALCARENITES
There are 3 distinct methods or tests used to determine the strength of calcarenite which are needle penetration test, unconfined compression test, and direct shear box test.
3.1. Needle penetration test
This form of test is done on site on an outcrop rock that is not disturbed; this is usually done by extracting a sample material for oncoming laboratory work. The penetration tests are done on two different sections of outcrop with an in-between distance of about 15 metres. A frequently used apparatus is a spring-loaded pocket penetrometer made by Eijelkamp, the Netherlands. What makes it special is that it does not have a cone like most penetration instruments but has a needle …show more content…
PROBLEMS ASSOCIATED WITH BUILDING ON LANDS WITH CALCARENITE.
When it comes to problems that are associated with building on grounds with calcarenite, some are natural and some are inherent and they are as follows.
4.1. Weathering
When the calcarenite is subjected to exposure to different atmospheric conditions it deteriorates due to natural effect of rain, wind and thermal change. The rock is durable as water infiltrates it becomes extremely reactive when exposed to acids and then suffer deterioration. After it has deteriorated it can no longer withstand the pressure of the building on top of it and as a result, it sinks to the ground.
Since it is a natural factor very little can be done to counteract this or to solve the problem caused by weathering.
4.2. Erosion
Erosion is a result of general weathering and air caused abrasives may selectively wear away detailing on certain elevations based on the direction of occurring winds. It does not really affect the building precisely but the water the inhabitants of the building depend on. Sediments get deposited into water bodies and therefore dirty and pollute the water such that the dependents may fall sick of the water and also it reduces …show more content…
To avoid all that the feature should be left alone and preserved.
5. TEST DONE ON LABORATORY
5.1. NEEDLE PENETRATION TEST
The calcarenite belongs to the emael member of the Maastricht formation and was collected as a 0.4 by 0.4 by 0.5m3 blocks from a mine. It has grains well sorted and also well rounded and composed of fragments of marine organisms such as bivalves, echinoids, sponges, bryozoan, brachiopods, and peloids.
A few millimetre fossils lie parallel to the bedding. Intergranular pores occupy a variable but large volume. Intraparticle porosity is present within the shell fragments.
The emael calcarenite appears as a grain supported structure with no mud between the grains. Most grains are surrounded by a fringe of bladed cement. The mineral of the calcarenite consists of 95% of calcium carbonate. (Ngan-Tillard et al. 2011)
However it can cause damage as during the needle penetration testing, up to 1mm of the needle tip, the grains were crushed and compacted in a zone that looks like an extension of the needle tip. As the needle was pushed forward, the clay-sized crushed material was further compacted I a 0.55mm thick dense powdery zone surrounding the shaft of the needle and migrated into the pores of the adjacent intact material. (Bexavanisetal,
There are 3 distinct methods or tests used to determine the strength of calcarenite which are needle penetration test, unconfined compression test, and direct shear box test.
3.1. Needle penetration test
This form of test is done on site on an outcrop rock that is not disturbed; this is usually done by extracting a sample material for oncoming laboratory work. The penetration tests are done on two different sections of outcrop with an in-between distance of about 15 metres. A frequently used apparatus is a spring-loaded pocket penetrometer made by Eijelkamp, the Netherlands. What makes it special is that it does not have a cone like most penetration instruments but has a needle …show more content…
PROBLEMS ASSOCIATED WITH BUILDING ON LANDS WITH CALCARENITE.
When it comes to problems that are associated with building on grounds with calcarenite, some are natural and some are inherent and they are as follows.
4.1. Weathering
When the calcarenite is subjected to exposure to different atmospheric conditions it deteriorates due to natural effect of rain, wind and thermal change. The rock is durable as water infiltrates it becomes extremely reactive when exposed to acids and then suffer deterioration. After it has deteriorated it can no longer withstand the pressure of the building on top of it and as a result, it sinks to the ground.
Since it is a natural factor very little can be done to counteract this or to solve the problem caused by weathering.
4.2. Erosion
Erosion is a result of general weathering and air caused abrasives may selectively wear away detailing on certain elevations based on the direction of occurring winds. It does not really affect the building precisely but the water the inhabitants of the building depend on. Sediments get deposited into water bodies and therefore dirty and pollute the water such that the dependents may fall sick of the water and also it reduces …show more content…
To avoid all that the feature should be left alone and preserved.
5. TEST DONE ON LABORATORY
5.1. NEEDLE PENETRATION TEST
The calcarenite belongs to the emael member of the Maastricht formation and was collected as a 0.4 by 0.4 by 0.5m3 blocks from a mine. It has grains well sorted and also well rounded and composed of fragments of marine organisms such as bivalves, echinoids, sponges, bryozoan, brachiopods, and peloids.
A few millimetre fossils lie parallel to the bedding. Intergranular pores occupy a variable but large volume. Intraparticle porosity is present within the shell fragments.
The emael calcarenite appears as a grain supported structure with no mud between the grains. Most grains are surrounded by a fringe of bladed cement. The mineral of the calcarenite consists of 95% of calcium carbonate. (Ngan-Tillard et al. 2011)
However it can cause damage as during the needle penetration testing, up to 1mm of the needle tip, the grains were crushed and compacted in a zone that looks like an extension of the needle tip. As the needle was pushed forward, the clay-sized crushed material was further compacted I a 0.55mm thick dense powdery zone surrounding the shaft of the needle and migrated into the pores of the adjacent intact material. (Bexavanisetal,