| ティーキューブ擁壁の内圧の算定 |
|
|
|
| １．設計内圧の基礎式 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
内圧はサイロの設計に用いられるJanssen（ヤンセン）式により算定する． |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Janssen式は次のとおりである． |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
鉛直方向の圧力 |
|
|
|
|
Pv= |
|
|
|
|
|
|
|
|
|
|
水平方向の圧力 |
|
|
|
|
ph= |
k･pv |
|
|
|
|
|
|
|
|
|
|
|
|
|
壁面摩擦力 |
|
|
|
|
|
pf= |
μ･pv |
|
|
|
|
|
|
|
|
|
|
|
|
ここで |
μ; |
壁面と内容物との間の摩擦係数 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
D; |
サイロの内径 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
γ; |
内容物の単位体積重量 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
k; |
Rankineの土圧係数 |
= |
|
φ; |
内容物の内部摩擦角 |
|
|
|
|
|
|
|
|
x: |
深さ |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
ここで，式中のD/4は，平面形状の面積と周長の比であり，円形以外に拡張すると |
|
|
|
|
下式のとおりとなる． |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
鉛直方向の圧力 |
|
|
|
|
Pv= |
|
|
|
|
|
|
|
|
|
|
ここで |
α； |
換算幅 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
円形 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
正方形 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
正三角形 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
長方形 |
|
短辺をD，長辺をLとし |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
β= |
L/Dとすると |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
帯状の場合 |
|
→ |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| ２．△ T-1050タイプ |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
辺長 |
|
|
|
|
|
D= |
|
|
|
|
0.9 |
m |
|
|
|
|
|
|
|
|
|
|
中詰材の単位重量 |
|
|
γ= |
|
|
|
|
20 |
kN/m3 |
|
|
|
|
|
|
|
|
|
中詰材の内部摩擦角 |
|
|
φ= |
|
|
|
|
35 |
° |
|
|
|
|
|
|
|
|
|
|
中詰材の壁面摩擦角 |
|
|
δ= |
2/3･φ = |
|
23 |
° |
|
|
|
|
|
|
|
|
|
|
中詰材の壁面との摩擦係数 |
μ= |
tanδ = |
0.431 |
|
|
|
|
|
|
|
|
|
|
|
ランキン土圧係数 |
|
|
k= |
|
|
= |
0.271 |
|
|
|
|
|
|
|
|
|
|
|
高さ |
|
|
|
|
|
x= |
|
|
|
5.0 |
m |
|
|
|
|
|
|
|
|
|
|
換算幅 |
|
正方形 |
|
|
|
|
|
= |
0.13 |
m |
|
|
|
|
|
|
|
|
|
|
鉛直圧力 |
|
|
|
|
|
|
|
|
|
|
|
22.0 |
kN/m2 |
|
|
|
|
|
|
水平圧力 |
|
|
|
|
ph= |
k･pv= |
|
|
|
|
5.96 |
kN/m2 |
|
|
|
|
|
|
壁面摩擦力 |
|
|
|
|
pf= |
μ･kv= |
|
|
|
|
9.48 |
kN/m2 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| ３．□ F-1050タイプ |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
辺長 |
|
|
|
|
|
D= |
|
|
|
|
0.9 |
m |
|
|
|
|
|
|
|
|
|
|
中詰材の単位重量 |
|
|
γ= |
|
|
|
|
20 |
kN/m3 |
|
|
|
|
|
|
|
|
|
中詰材の内部摩擦角 |
|
|
φ= |
|
|
|
|
35 |
° |
|
|
|
|
|
|
|
|
|
|
中詰材の壁面摩擦角 |
|
|
δ= |
2/3･φ = |
|
23 |
° |
|
|
|
|
|
|
|
|
|
|
中詰材の壁面との摩擦係数 |
μ= |
tanδ = |
0.431 |
|
|
|
|
|
|
|
|
|
|
|
ランキン土圧係数 |
|
|
k= |
|
|
= |
0.271 |
|
|
|
|
|
|
|
|
|
|
|
高さ |
|
|
|
|
|
x= |
|
|
|
5.0 |
m |
|
|
|
|
|
|
|
|
|
|
換算幅 |
|
正方形 |
|
|
α= |
D/4 |
|
= |
0.225 |
m |
|
|
|
|
|
|
|
|
|
|
鉛直圧力 |
|
|
|
|
|
35.6 |
kN/m2 |
|
|
|
|
|
|
水平圧力 |
|
|
|
|
ph= |
k･pv= |
|
|
|
|
9.66 |
kN/m2 |
|
|
|
|
|
|
壁面摩擦力 |
|
|
|
|
pf= |
μ･kv= |
|
|
|
|
15.4 |
kN/m2 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| ４．設計内圧 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
以上より，擁壁の高さは最大でも5m程度と予想されるため，良質材料を使用した場合， |
|
|
|
設計内圧は10kN/m2を考慮すれば十分である． |
|
|
|
|
|
|
|
|
|
|
|
|
|
なお，△ T-1050タイプについては，中詰材料の質を特に指定しない． |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
