3. Construction solution.
The third chapter examines the construction solution of this building.
3.1 Foundation.
In project we use precast strip foundation from reinforced concrete. Cushion has size 1200x300 millimeters. Level of laying of foundation must be below then frost depth. On this basis we can take foundation level of laying 2,8 m. Also foundation level of laying depend on various factor: subterranean water, for example. There are perimeter walk. Wide is 1 m.
3.2 Basement
In this case, basement is used for technical purposes (setting of public water main, heating system and other utility systems). Height of basement is 2,5 m, floor is laid ground. Floor consists of mud slab and sand cement screed. There are four vent-holes and entrance from outside.
3.3 Walls.
Almost all walls in building are load-bearing expect gypsum board partition.
The other wall is 350 mm. Walls consists of three layers with effective insulate. Inside layer of wall is frame and consist of concrete slab 200 mm. Middle layer – thermal covering 100 mm, face layer is decorative. We use loam board slab for thermal covering, face acrylic water-proof paint for facing work and diagonal frame from weathering steel for coupling between the layers. Internal load-bearing wall are made of reinforced concrete.
3.4 Floor.
A floor in residential and public buildings must meet the requirements of strength, flexibility and quietness. In living rooms we use laminate, in bathrooms we use stoneware tile, in tambour and stairwells we use concrete filling floors. Floor stabs anchor in one for create hard disk cover.
3.5 Doors
Height of doors is 2,1 m. We have provided thresholds for external doors. Door leafs are hang on hinge, that give able to take off door leaf for replacement and repair. We equip doors box lock.
3.6 Roof.
Roof consist from reinforced concrete panel, vapour barrier, heat insulating mats, sand cement screed and two layers of isoplast. Slop ratio is 2,3 %. Eneathment is carried out from 2 invent 500 mm and funnel 300 mm. There are elevator machine room for convenient access to elevator shaft. Scavenged fencing installed for prevention snow bag.
4. Calculate of soundproofing.
Benchmark data: density, ρ=2500 kg/m3;
wall thickness h=180 mm.
Calculate.
We define surface density of building envelop:
We define amplitude-response curve of building envelop soundproofing.
We must find coordinates of the point В on the amplitude-response curve.
X-coordinate of point (fв) is define in table of the applicable Code Design. It depend of thickness and density of construction.
We define B y-coordinate. It depend of surface density:
|
Amplitude, Hz |
The normal value of insulation |
Estimated value insulation |
Adverse deviations dB |
Offset |
Adverse deviations dB |
|
100 |
33 |
36 |
+ |
29 |
+ |
|
125 |
36 |
36 |
0 |
32 |
+ |
|
160 |
39 |
36 |
-3 |
35 |
+ |
|
200 |
42 |
36 |
-6 |
38 |
-2 |
|
250 |
45 |
38 |
-7 |
41 |
-3 |
|
315 |
48 |
40 |
-8 |
44 |
-4 |
|
400 |
51 |
42 |
-9 |
47 |
-5 |
|
500 |
52 |
44 |
-8 |
48 |
-4 |
|
630 |
53 |
46 |
-7 |
49 |
-3 |
|
800 |
54 |
48 |
-6 |
50 |
-2 |
|
1000 |
55 |
50 |
-5 |
51 |
-1 |
|
1250 |
56 |
52 |
-4 |
52 |
0 |
|
1600 |
56 |
54 |
-2 |
52 |
+ |
|
2000 |
56 |
56 |
0 |
52 |
+ |
|
2500 |
56 |
58 |
+ |
52 |
+ |
|
3150 |
56 |
60 |
+ |
52 |
+ |
|
Amount of adverse deviation |
-65 |
-4 |
-24 | ||
If amount of adverse deviation more than 32dB, then appraisal curve shifts on 4 dB, that amount of adverse deviation was less than permissible value.
Index value of insulation is y-coordinate of offset appraisal curve on 500Hz.
We get the index value equal to insulation 48 dB. This reinforced panel is satisfies the requirements of sound insulation.