উত্তর সহ কয়েকটি অনুরুপ গুরুত্বপূর্ণ প্রশ্ন 1. Ordinary Portland Cement এর Initial Setting Time minimum কত minutes হয়-30 minutes. 2. Ordinary Portland Cement এর Final Setting Time minimum কত minutes হয়- 10 hours.

Explained: crushing strength (বিচূর্ণন শক্তি)। ইটের চাপ শক্তি নির্ণয়ের জন্য এ পরীক্ষা করা হয়। এ পরীক্ষা ৬ থেকে ৮টি পর্যায়ক্রমে সাজিয়ে কম্পেশন টেষ্ট মেশিনের সাহায্যে (Universal Testing machine) চাপ প্রয়োগ করা হয়। চাপ প্রয়োগ করার সময় ইটের বিচুর্ণন শক্তি নির্ণয় করা হয়। বিভিন্ন প্রকার ইটের ক্রাসিং স্ট্রেস্থ এর মান: ১ম শ্রেণির ইট =10.5MN/m²=10.5N/mm² ২য় শ্রেণির ইট =7.5MN/m²-7.5N/mm² ৩য় শ্রেণির ইট =3.5MN/mm² 3.5N/mm²

Explained: Granite is a hard light colored igneous rock used for building and monuments. Granite is composed mainly of quartz and feldpar with minor amounts of mica, amphiboles and other minerals. উত্তর সহ কয়েকটি অনুরূপ গুরুত্বপূর্ণ প্রশ্ন 1. The predominant constituent which for strength in granite is - Quartz responsible 2. The stone whose crushing strength is maximum, is- Granite 3. The bearing capacity of granite is generally - 30 to 35 kg/cm2 4. To obtain a very high strength concrete, use very fine grained-Granite Boul

Explained: The compressive strength of granite is 750 to 1350 kg/cm² or 70 to 130 mN/m²

Explained: Gneiss is a common and widely distributed type of metamorphic rock or silicious rock. Gneiss is a faliated siliceous rock in which the coarse mineral grains. have been arranged into a banded structure. উত্তর সহ কয়েকটি অনুরূপ গুরুত্বপূর্ণ প্রশ্ন 1. According to IS: 382-1963, a good aggregate should be-Chemically inert. Sufficiently strong. Hard and durable. 2. Saw dust can be rendered chemically inert by boiling it in water containing - Ferrous sulphate 3. As per ISI, rolled steel beam sections are classified Into- Five series

Explained-Laterite is chemically classified as Argillaceous rock Laterite is a red coloured clayey material wich forms a topsoil in tropical regions. It is hard when it is dry.

Explained:-Metamorphic rocks are formed by the metamorphism process. Some example of metamorphic rocks are slate, gneiss, schist, marble, soapstone etc. উত্তর সহ কয়েকটি অনুরূপ গুরুত্বপূন প্রশ্ন 1.The rock formed from the solidification of molten matter (magma) is called: igneous rocks.

Explained:সাধারণত H.L.L. হয়ে থাকে। 1. স্টিল বিষের সেকশন নিচের কোন আকৃতির হতে পারে- H 2. নিচের কোনটি আরসিসি বিমের উপাদান- সবগুলো। 3. RCC - Reinforced Cement Concrete. 4. RCC এর কোন উপাদানটি coarse aggregate - Stone. 5. RCC এর কোনটি helping materials- water. 6. RCC এর কোনটি binding materials -cement.

Explained: A first class brick shall not absorb more than th 1/6 of its dry weight when inunersed in water for 24 hours. The water absorption capacity for the first class bricks should be under 20%. উত্তর সহ কয়েকটি অনুরুপ গুরুত্বপূর্ণ প্রশ্ন 1. To obtain good bonding in brick masonry - First class bricks are used, Vertical joints in alternate urses are kept in plumb line. Eats are used where necessary 2. The type of pointing in which upper side of mortar joints is kept about 12 mm inside the face of the masonry and bottom is kept flushed with face of wall, is-Struck pointing 3. The wedge shaped bricks forming an arch ring. are called- Voussoirs 4. The maximum total settlement for isolated foundations on clayey soils should be limited to - 65 mm 5. The foundation which consists of a thick reinforced cement slab covering whole area to support heavy concentrated structural loads, is known as -Raft footing

উত্তর সহ কয়েকটি অনুরুপ গুরুত্বপূর্ণ প্রশ্ন In case of timber structures, the simple bending formula M fz may be applied for-- Rectangular beams up to 300 mm depth 2. The timber floor not spanning on the masonry wall but properly anchored to the wall gives - Loterol restraint but not rotational restraint 3. The advantage of a concrete pile over a timber pile, is-No restriction on length, No decay due to termites, Higher bearing capacity. 4. If 5 and H are strength and hardness index of a timber at 12% moisture content, the composite sleeper index, is-(S+10H)/20 5. The life of a wooden sleeper depends upon- Quality of its timber 6. Design of a timber beam in general is most critical in-Deflection

উত্তর সহ কয়েকটি অনুরুপ গুরুত্বপূর্ণ প্রশ্ন 1. Pick up the correct statement from the following:- A soil having pH value less than 7 is an acidic soil 2. For road pavements, the cement generally used, is- Rapid hardening cement 3. For construction of structures in sea water, the cement generally preferred to, is-Fortland-pozzolana 4. For the construction of thin R.C.C. structures, the type of cement to be avoided, is-Blast furnace slag Cement 5. The cement whose strength is a little lower than the ordinary cement during the first three months but attains afterwards the same strength, is known as Low-heat Fortland cement

Explained: House building and research institute (HBRI) -অনুসারে সিলেট বালির সূক্ষতা গুণাংকের মান ২.৩ হতে ২.৯ হয়ে থাকে তবে, সাধারণত সিলেট বালির সূক্ষতা গুণাংকের মান ২.৫ ধরা হয়।

উত্তর সহ কয়েকটি অনুরূপ গুরুত্বপূর্ণ প্রশ্ন 1. Ordinary Portland Cement এর Final Setting Time minimum কত minutes হয়- 10 hours. 2. The main ingredients of Portland cement are- Lime & Silica. 7. Portland cement এ Cao এর পরিমাণ- 6.3% 4.Portland cement এ SIO2 এর পরিমাণ- 22%. 5. Portland cement Al2O3= 7%, Fe2O3=3%, MgO-2%, SO2=2%, Alkalies =1%.

Explained.-Poisson's ratio values for different materials Clay-0.30-0.45 Material-0.30-0.31 Stainless steel-0.27-0.30 Steel-0.21-0.26 উত্তর সহ কয়েকটি অনুরুপ গুরুত্বপূর্ণ প্রশ্ন 1. Poisson's ratio for steel within elastic limit, ranges from-0.25 to 0.33 2 Poisson's ratio for concrete - Increases with richer mixes 3. The ratio of lateral strain to axial strain of a homogeneous material, is known - Poisson's ratio 4 The value of Poisson's ratio always remains Less than one

Explained:- সিমেন্টের উপাদানগুলো হচ্ছে- CaO, SiO₂, MgO, Al₂O3, SO3,FC₂O₂ উত্তর সহ কয়েকটি অনুরুপ শুরুত্বপূর্ণ প্রশ্ন 1. নিচের কোনটি সিমেন্টের উপাদান নয় -Alo3. 2. Cement এ চুনের পরিমাণ কত- 63%, 3. Cement এ সিলিকার পরিমাণ কত- 22%. 4. Cement এ জিপসামের পরিমাণ কত-3% 5. Cement এ সেটিং টাইম মন্থর বারে কোনটি- জিপসাম।

Explained:-The specific gravity of stone is 2.00-2.60 But the specific gravity of stone should not less than 2.5 উত্তর সহ কয়েকটি অনুরূপ গুরুত্বপূর্ণ প্রশ্ন 1. Center of buoyancy is the- Centroid of the displaced volume of fluid 2. Metacentric height is the distance between the metacentre and-Center of gravity 3. The point in the immersed body through which the resultant pressure of the liquid may be taken to act is known as-Center of pressure 4. According to the principle of buoyancy a body totally or partially immersed in a fluid will be lifted up by a force equal to - Weight of the fluid displaced by the body 5. The two important forces for a floating body are- Eusyancy, gravity

Explained: A good building stone shouldn't absorb more than 5% water but stone absorbing more than 10% should be rejected. উত্তর সহ কয়েকটি অনুরুপ গুরুত্বপূর্ণ প্রশ্ন 1. Best ballast contains stones varying in size from -2.0 cm to 5 cm 2. Ballast packed below and around the sleepers to transfer the load from sleepers to formation, generally consists of --Broken stones, Gravels, Moorum 3. The important test to be conducted on a stone used in docks and harbours is - Weight fast 4. The type of stone masonry in which stones of same height are laid in layers, is called --Course rub Ple masonry

Explained The rofcks which contain silica in predominant amont are called as siliceious rocks. Presence of a large amount of free silica makes them harden and durable. Granite, greiss, quartzite, chert, etc. are example of siliccious rocks. উত্তর সহ কয়েকটি অনুরূপ গুরুত্বপূর্ণ প্রশ্ন 1. Percussion drilling is unsuitable in-Consolidated rocks 2. The type of pile which is driven at an inclination to resist inclined forces is known as-Eatter pile 3. The maximum bearing capacity of soil is that of- Hard rocka 4. Pick up the correct statement from the following : Sandmists of course particles of silica formal due to the Jisintegration frocks

Explained-a marble is an example of a metamorphic rock: it is compoised of recrystallized carbonated minerals, most commonly calcite or dolomite. উত্তর সহ কয়েকটি অনুরুপ গুরুত্বপূর্ণ প্রশ্ন 1. The rock formed from the solidification of molten matter (magma) is called- Ignesus rock 2. The maximum bearing capacity of soil is that of- Hard rocks 3. A solid core of rock is formed inside the cylinder in the case of- Diamond drilling

Explained: The rocks in which clay content is predominant are called argillaccous rock. The rocks are soft in nature and with the presence of water they can be crumbled easily some of the argillaceous rocks are shale, slate, kaolin, literate etc.