【摘要】 西安地裂缝是近年陆续出现的一种张拉裂缝,它的方位通常呈东北向。由于工业及民用过量地采取承压水,增大了承压水层土粒间的有效压力,引起土层的固结沉降,在沉降过大及不均匀沉降的影响下,使地面产生了这种张拉裂缝。由粘性土的极限平衡理论证明并导出裂缝的极限垂直深度 Z₀为:Z₀=（2c）/（γ）tg（45°+（（?））/（2））K、太沙基得出相似的计算公式为:Z₀=（2.67c）/（γ）tg（45°+■）/（2）)这里 c■分别为内聚力、容重、及内摩擦角房屋基础避让裂缝的安全距离 L_?按规范 TJ7-74建议并进行适当修正后的计算公式为:对条形基础:L_b=Z₀+3.5B+（D）/（tgα）对矩基形础:L_b=Z₀+2.5B+（D）/（tgα）这里 B 为基础埋深,α≤45°的土的稳定坡角,D 为基础埋置深度,其他符号同前。考虑现场施工等影响,上述安全避让距离的计算值尚须乘一系数 K 值,K 取1.2～1.4。更多还原

【Abstract】 Ground cracking occurred successively at Xi’an region in the last deca- de is not a matter of no importance.In case the ground cracking beneath he foundation of a building takes place,the structure would consequent- ly be damaged. In this paper,the cause of the formation of ground cracking is expound- ed,and the safety distance of building foundation to keep away from the cracking is proposed.更多还原